scons
a software construction tool
1. scons.1.man
Manpage of SCONS
SCONS
Section: User Commands (1)Updated: August 2010
Index Return to Main Contents
NAME
scons - a software construction toolSYNOPSIS
scons [ options... ] [ name=val... ] [ targets... ]DESCRIPTION
The scons utility builds software (or other files) by determining which component pieces must be rebuilt and executing the necessary commands to rebuild them.
By default, scons searches for a file named SConstruct, Sconstruct, or sconstruct (in that order) in the current directory and reads its configuration from the first file found. An alternate file name may be specified via the -f option.
The SConstruct file can specify subsidiary configuration files using the SConscript() function. By convention, these subsidiary files are named SConscript, although any name may be used. (Because of this naming convention, the term "SConscript files" is sometimes used to refer generically to all scons configuration files, regardless of actual file name.)
The configuration files specify the target files to be built, and (optionally) the rules to build those targets. Reasonable default rules exist for building common software components (executable programs, object files, libraries), so that for most software projects, only the target and input files need be specified.
Before reading the SConstruct file, scons looks for a directory named site_scons in the directory containing the SConstruct file; if it exists, site_scons is added to sys.path, the file site_scons/site_init.py, is evaluated if it exists, and the directory site_scons/site_tools is added to the default toolpath if it exist. See the --no-site-dir and --site-dir options for more details.
scons reads and executes the SConscript files as Python scripts, so you may use normal Python scripting capabilities (such as flow control, data manipulation, and imported Python libraries) to handle complicated build situations. scons, however, reads and executes all of the SConscript files before it begins building any targets. To make this obvious, scons prints the following messages about what it is doing:
-
$ scons foo.out scons: Reading SConscript files ... scons: done reading SConscript files. scons: Building targets ... cp foo.in foo.out scons: done building targets. $
The status messages (everything except the line that reads "cp foo.in foo.out") may be suppressed using the -Q option.
scons does not automatically propagate the external environment used to execute scons to the commands used to build target files. This is so that builds will be guaranteed repeatable regardless of the environment variables set at the time scons is invoked. This also means that if the compiler or other commands that you want to use to build your target files are not in standard system locations, scons will not find them unless you explicitly set the PATH to include those locations. Whenever you create an scons construction environment, you can propagate the value of PATH from your external environment as follows:
-
import os env = Environment(ENV = {'PATH' : os.environ['PATH']})
Similarly, if the commands use external environment variables like $PATH, $HOME, $JAVA_HOME, $LANG, $SHELL, $TERM, etc., these variables can also be explicitly propagated:
-
import os env = Environment(ENV = {'PATH' : os.environ['PATH'], 'HOME' : os.environ['HOME']})
Or you may explicitly propagate the invoking user's complete external environment:
-
import os env = Environment(ENV = os.environ)
This comes at the expense of making your build dependent on the user's environment being set correctly, but it may be more convenient for many configurations.
scons can scan known input files automatically for dependency information (for example, #include statements in C or C++ files) and will rebuild dependent files appropriately whenever any "included" input file changes. scons supports the ability to define new scanners for unknown input file types.
scons knows how to fetch files automatically from SCCS or RCS subdirectories using SCCS, RCS or BitKeeper.
scons is normally executed in a top-level directory containing a SConstruct file, optionally specifying as command-line arguments the target file or files to be built.
By default, the command
-
scons
will build all target files in or below the current directory. Explicit default targets (to be built when no targets are specified on the command line) may be defined the SConscript file(s) using the Default() function, described below.
Even when Default() targets are specified in the SConscript file(s), all target files in or below the current directory may be built by explicitly specifying the current directory (.) as a command-line target:
-
scons .
Building all target files, including any files outside of the current directory, may be specified by supplying a command-line target of the root directory (on POSIX systems):
-
scons /
or the path name(s) of the volume(s) in which all the targets should be built (on Windows systems):
-
scons C:\ D:\
To build only specific targets, supply them as command-line arguments:
-
scons foo bar
in which case only the specified targets will be built (along with any derived files on which they depend).
Specifying "cleanup" targets in SConscript files is not usually necessary. The -c flag removes all files necessary to build the specified target:
-
scons -c .
to remove all target files, or:
-
scons -c build export
to remove target files under build and export. Additional files or directories to remove can be specified using the Clean() function. Conversely, targets that would normally be removed by the -c invocation can be prevented from being removed by using the NoClean() function.
A subset of a hierarchical tree may be built by remaining at the top-level directory (where the SConstruct file lives) and specifying the subdirectory as the target to be built:
-
scons src/subdir
or by changing directory and invoking scons with the -u option, which traverses up the directory hierarchy until it finds the SConstruct file, and then builds targets relatively to the current subdirectory:
-
cd src/subdir scons -u .
scons supports building multiple targets in parallel via a -j option that takes, as its argument, the number of simultaneous tasks that may be spawned:
-
scons -j 4
builds four targets in parallel, for example.
scons can maintain a cache of target (derived) files that can be shared between multiple builds. When caching is enabled in a SConscript file, any target files built by scons will be copied to the cache. If an up-to-date target file is found in the cache, it will be retrieved from the cache instead of being rebuilt locally. Caching behavior may be disabled and controlled in other ways by the --cache-force, --cache-disable, and --cache-show command-line options. The --random option is useful to prevent multiple builds from trying to update the cache simultaneously.
Values of variables to be passed to the SConscript file(s) may be specified on the command line:
-
scons debug=1 .
These variables are available in SConscript files through the ARGUMENTS dictionary, and can be used in the SConscript file(s) to modify the build in any way:
-
if ARGUMENTS.get('debug', 0): env = Environment(CCFLAGS = '-g') else: env = Environment()
The command-line variable arguments are also available in the ARGLIST list, indexed by their order on the command line. This allows you to process them in order rather than by name, if necessary. ARGLIST[0] returns a tuple containing (argname, argvalue). A Python exception is thrown if you try to access a list member that does not exist.
scons requires Python version 2.4 or later. There should be no other dependencies or requirements to run scons.
By default, scons knows how to search for available programming tools on various systems. On Windows systems, scons searches in order for the Microsoft Visual C++ tools, the MinGW tool chain, the Intel compiler tools, and the PharLap ETS compiler. On OS/2 systems, scons searches in order for the OS/2 compiler, the GCC tool chain, and the Microsoft Visual C++ tools, On SGI IRIX, IBM AIX, Hewlett Packard HP-UX, and Sun Solaris systems, scons searches for the native compiler tools (MIPSpro, Visual Age, aCC, and Forte tools respectively) and the GCC tool chain. On all other platforms, including POSIX (Linux and UNIX) platforms, scons searches in order for the GCC tool chain, the Microsoft Visual C++ tools, and the Intel compiler tools. You may, of course, override these default values by appropriate configuration of Environment construction variables.
OPTIONS
In general, scons supports the same command-line options as GNU make, and many of those supported by cons.
- -b
-
Ignored for compatibility with non-GNU versions of
make.
- -c, --clean, --remove
-
Clean up by removing all target files for which a construction
command is specified.
Also remove any files or directories associated to the construction command
using the
Clean()
function.
Will not remove any targets specified by the
NoClean()
function.
- --cache-debug=file
-
Print debug information about the
CacheDir()
derived-file caching
to the specified
file.
If
file
is
-
(a hyphen),
the debug information are printed to the standard output.
The printed messages describe what signature file names are
being looked for in, retrieved from, or written to the
CacheDir()
directory tree.
- --cache-disable, --no-cache
-
Disable the derived-file caching specified by
CacheDir().
scons
will neither retrieve files from the cache
nor copy files to the cache.
- --cache-force, --cache-populate
-
When using
CacheDir(),
populate a cache by copying any already-existing, up-to-date
derived files to the cache,
in addition to files built by this invocation.
This is useful to populate a new cache with
all the current derived files,
or to add to the cache any derived files
recently built with caching disabled via the
--cache-disable
option.
- --cache-show
-
When using
CacheDir()
and retrieving a derived file from the cache,
show the command
that would have been executed to build the file,
instead of the usual report,
"Retrieved `file' from cache."
This will produce consistent output for build logs,
regardless of whether a target
file was rebuilt or retrieved from the cache.
- --config=mode
-
This specifies how the
Configure
call should use or generate the
results of configuration tests.
The option should be specified from
among the following choices:
- --config=auto
-
scons will use its normal dependency mechanisms
to decide if a test must be rebuilt or not.
This saves time by not running the same configuration tests
every time you invoke scons,
but will overlook changes in system header files
or external commands (such as compilers)
if you don't specify those dependecies explicitly.
This is the default behavior.
- --config=force
-
If this option is specified,
all configuration tests will be re-run
regardless of whether the
cached results are out of date.
This can be used to explicitly
force the configuration tests to be updated
in response to an otherwise unconfigured change
in a system header file or compiler.
- --config=cache
-
If this option is specified,
no configuration tests will be rerun
and all results will be taken from cache.
Note that scons will still consider it an error
if --config=cache is specified
and a necessary test does not
yet have any results in the cache.
- -C directory, --directory=directory
-
Change to the specified
directory
before searching for the
SConstruct,
Sconstruct,
or
sconstruct
file, or doing anything
else. Multiple
-C
options are interpreted
relative to the previous one, and the right-most
-C
option wins. (This option is nearly
equivalent to
-f directory/SConstruct,
except that it will search for
SConstruct,
Sconstruct,
or
sconstruct
in the specified directory.)
- -D
-
Works exactly the same way as the
-u
option except for the way default targets are handled.
When this option is used and no targets are specified on the command line,
all default targets are built, whether or not they are below the current
directory.
- --debug=type
-
Debug the build process.
type
specifies what type of debugging:
- --debug=count
-
Print how many objects are created
of the various classes used internally by SCons
before and after reading the SConscript files
and before and after building targets.
This is not supported when SCons is executed with the Python
-O
(optimized) option
or when the SCons modules
have been compiled with optimization
(that is, when executing from
*.pyo
files).
- --debug=dtree
-
A synonym for the newer
--tree=derived
option.
This will be deprecated in some future release
and ultimately removed.
- --debug=explain
-
Print an explanation of precisely why
scons
is deciding to (re-)build any targets.
(Note: this does not print anything
for targets that are
not
rebuilt.)
- --debug=findlibs
-
Instruct the scanner that searches for libraries
to print a message about each potential library
name it is searching for,
and about the actual libraries it finds.
- --debug=includes
-
Print the include tree after each top-level target is built.
This is generally used to find out what files are included by the sources
of a given derived file:
-
$ scons --debug=includes foo.o
-
- --debug=memoizer
-
Prints a summary of hits and misses using the Memoizer,
an internal subsystem that counts
how often SCons uses cached values in memory
instead of recomputing them each time they're needed.
- --debug=memory
-
Prints how much memory SCons uses
before and after reading the SConscript files
and before and after building targets.
- --debug=nomemoizer
-
A deprecated option preserved for backwards compatibility.
- --debug=objects
-
Prints a list of the various objects
of the various classes used internally by SCons.
- --debug=pdb
-
Re-run SCons under the control of the
pdb
Python debugger.
- --debug=presub
-
Print the raw command line used to build each target
before the construction environment variables are substituted.
Also shows which targets are being built by this command.
Output looks something like this:
-
$ scons --debug=presub Building myprog.o with action(s): $SHCC $SHCFLAGS $SHCCFLAGS $CPPFLAGS $_CPPINCFLAGS -c -o $TARGET $SOURCES ...
-
- --debug=stacktrace
-
Prints an internal Python stack trace
when encountering an otherwise unexplained error.
- --debug=stree
-
A synonym for the newer
--tree=all,status
option.
This will be deprecated in some future release
and ultimately removed.
- --debug=time
-
Prints various time profiling information:
the time spent executing each individual build command;
the total build time (time SCons ran from beginning to end);
the total time spent reading and executing SConscript files;
the total time spent SCons itself spend running
(that is, not counting reading and executing SConscript files);
and both the total time spent executing all build commands
and the elapsed wall-clock time spent executing those build commands.
(When
scons
is executed without the
-j
option,
the elapsed wall-clock time will typically
be slightly longer than the total time spent
executing all the build commands,
due to the SCons processing that takes place
in between executing each command.
When
scons
is executed
with
the
-j
option,
and your build configuration allows good parallelization,
the elapsed wall-clock time should
be significantly smaller than the
total time spent executing all the build commands,
since multiple build commands and
intervening SCons processing
should take place in parallel.)
- --debug=tree
-
A synonym for the newer
--tree=all
option.
This will be deprecated in some future release
and ultimately removed.
- --diskcheck=types
-
Enable specific checks for
whether or not there is a file on disk
where the SCons configuration expects a directory
(or vice versa),
and whether or not RCS or SCCS sources exist
when searching for source and include files.
The
types
argument can be set to:
all,
to enable all checks explicitly
(the default behavior);
none,
to disable all such checks;
match,
to check that files and directories on disk
match SCons' expected configuration;
rcs,
to check for the existence of an RCS source
for any missing source or include files;
sccs,
to check for the existence of an SCCS source
for any missing source or include files.
Multiple checks can be specified separated by commas;
for example,
--diskcheck=sccs,rcs
would still check for SCCS and RCS sources,
but disable the check for on-disk matches of files and directories.
Disabling some or all of these checks
can provide a performance boost for large configurations,
or when the configuration will check for files and/or directories
across networked or shared file systems,
at the slight increased risk of an incorrect build
or of not handling errors gracefully
(if include files really should be
found in SCCS or RCS, for example,
or if a file really does exist
where the SCons configuration expects a directory).
- --duplicate=ORDER
-
There are three ways to duplicate files in a build tree: hard links,
soft (symbolic) links and copies. The default behaviour of SCons is to
prefer hard links to soft links to copies. You can specify different
behaviours with this option.
ORDER
must be one of
hard-soft-copy
(the default),
soft-hard-copy,
hard-copy,
soft-copy
or
copy.
SCons will attempt to duplicate files using
the mechanisms in the specified order.
- -f file, --file=file, --makefile=file, --sconstruct=file
-
Use
file
as the initial SConscript file.
Multiple
-f
options may be specified,
in which case
scons
will read all of the specified files.
- -h, --help
-
Print a local help message for this build, if one is defined in
the SConscript file(s), plus a line that describes the
-H
option for command-line option help. If no local help message
is defined, prints the standard help message about command-line
options. Exits after displaying the appropriate message.
- -H, --help-options
-
Print the standard help message about command-line options and
exit.
- -i, --ignore-errors
-
Ignore all errors from commands executed to rebuild files.
- -I directory, --include-dir=directory
-
Specifies a
directory
to search for
imported Python modules. If several
-I
options
are used, the directories are searched in the order specified.
- --implicit-cache
- Cache implicit dependencies. This causes scons to use the implicit (scanned) dependencies from the last time it was run instead of scanning the files for implicit dependencies. This can significantly speed up SCons, but with the following limitations:
- scons will not detect changes to implicit dependency search paths (e.g. CPPPATH, LIBPATH) that would ordinarily cause different versions of same-named files to be used.
-
scons
will miss changes in the implicit dependencies
in cases where a new implicit
dependency is added earlier in the implicit dependency search path
(e.g.
CPPPATH, LIBPATH)
than a current implicit dependency with the same name.
- --implicit-deps-changed
-
Forces SCons to ignore the cached implicit dependencies. This causes the
implicit dependencies to be rescanned and recached. This implies
--implicit-cache.
- --implicit-deps-unchanged
-
Force SCons to ignore changes in the implicit dependencies.
This causes cached implicit dependencies to always be used.
This implies
--implicit-cache.
- --interactive
-
Starts SCons in interactive mode.
The SConscript files are read once and a
scons>>>
prompt is printed.
Targets may now be rebuilt by typing commands at interactive prompt
without having to re-read the SConscript files
and re-initialize the dependency graph from scratch.
SCons interactive mode supports the following commands:
-
- build[OPTIONS] [TARGETS] ...
-
Builds the specified
TARGETS
(and their dependencies)
with the specified
SCons command-line
OPTIONS.
b
and
scons
are synonyms.
The following SCons command-line options affect the build command:
-
--cache-debug=FILE --cache-disable, --no-cache --cache-force, --cache-populate --cache-show --debug=TYPE -i, --ignore-errors -j N, --jobs=N -k, --keep-going -n, --no-exec, --just-print, --dry-run, --recon -Q -s, --silent, --quiet --taskmastertrace=FILE --tree=OPTIONS
-
-
Any other SCons command-line options that are specified
do not cause errors
but have no effect on the
build
command
(mainly because they affect how the SConscript files are read,
which only happens once at the beginning of interactive mode).
- clean[OPTIONS] [TARGETS] ...
-
Cleans the specified
TARGETS
(and their dependencies)
with the specified options.
c
is a synonym.
This command is itself a synonym for
build --clean
- exit
-
Exits SCons interactive mode.
You can also exit by terminating input
(CTRL+D on UNIX or Linux systems,
CTRL+Z on Windows systems).
- help[COMMAND]
-
Provides a help message about
the commands available in SCons interactive mode.
If
COMMAND
is specified,
h
and
?
are synonyms.
- shell[COMMANDLINE]
-
Executes the specified
COMMANDLINE
in a subshell.
If no
COMMANDLINE
is specified,
executes the interactive command interpreter
specified in the
SHELL
environment variable
(on UNIX and Linux systems)
or the
COMSPEC
environment variable
(on Windows systems).
sh
and
!
are synonyms.
- version
- Prints SCons version information.
-
-
An empty line repeats the last typed command.
Command-line editing can be used if the
readline
module is available.
-
$ scons --interactive scons: Reading SConscript files ... scons: done reading SConscript files. scons>>> build -n prog scons>>> exit
-
- -j N, --jobs=N
-
Specifies the number of jobs (commands) to run simultaneously.
If there is more than one
-j
option, the last one is effective.
- -k, --keep-going
-
Continue as much as possible after an error. The target that
failed and those that depend on it will not be remade, but other
targets specified on the command line will still be processed.
- -m
-
Ignored for compatibility with non-GNU versions of
make.
- --max-drift=SECONDS
-
Set the maximum expected drift in the modification time of files to
SECONDS.
This value determines how long a file must be unmodified
before its cached content signature
will be used instead of
calculating a new content signature (MD5 checksum)
of the file's contents.
The default value is 2 days, which means a file must have a
modification time of at least two days ago in order to have its
cached content signature used.
A negative value means to never cache the content
signature and to ignore the cached value if there already is one. A value
of 0 means to always use the cached signature,
no matter how old the file is.
- --md5-chunksize=KILOBYTES
-
Set the block size used to compute MD5 signatures to
KILOBYTES.
This value determines the size of the chunks which are read in at once when
computing MD5 signatures. Files below that size are fully stored in memory
before performing the signature computation while bigger files are read in
block-by-block. A huge block-size leads to high memory consumption while a very
small block-size slows down the build considerably.
The default value is to use a chunk size of 64 kilobytes, which should be appropriate for most uses.
- -n, --just-print, --dry-run, --recon
-
No execute. Print the commands that would be executed to build
any out-of-date target files, but do not execute the commands.
- --no-site-dir
-
Prevents the automatic addition of the standard
site_scons
dir to
sys.path.
Also prevents loading the
site_scons/site_init.py
module if it exists, and prevents adding
site_scons/site_tools
to the toolpath.
- --profile=file
-
Run SCons under the Python profiler
and save the results in the specified
file.
The results may be analyzed using the Python
pstats module.
- -q, --question
- Do not run any commands, or print anything. Just return an exit status that is zero if the specified targets are already up to date, non-zero otherwise.
- -Q
-
Quiets SCons status messages about
reading SConscript files,
building targets
and entering directories.
Commands that are executed
to rebuild target files are still printed.
- --random
-
Build dependencies in a random order. This is useful when
building multiple trees simultaneously with caching enabled,
to prevent multiple builds from simultaneously trying to build
or retrieve the same target files.
- -s, --silent, --quiet
-
Silent. Do not print commands that are executed to rebuild
target files.
Also suppresses SCons status messages.
- -S, --no-keep-going, --stop
-
Ignored for compatibility with GNU
make.
- --site-dir=dir
-
Uses the named dir as the site dir rather than the default
site_scons
dir. This dir will get prepended to
sys.path,
the module
dir/site_init.py
will get loaded if it exists, and
dir/site_tools
will get added to the default toolpath.
- --stack-size=KILOBYTES
-
Set the size stack used to run threads to
KILOBYTES.
This value determines the stack size of the threads used to run jobs.
These are the threads that execute the actions of the builders for the
nodes that are out-of-date.
Note that this option has no effect unless the
num_jobs
option, which corresponds to -j and --jobs, is larger than one. Using
a stack size that is too small may cause stack overflow errors. This
usually shows up as segmentation faults that cause scons to abort
before building anything. Using a stack size that is too large will
cause scons to use more memory than required and may slow down the entire
build process.
The default value is to use a stack size of 256 kilobytes, which should be appropriate for most uses. You should not need to increase this value unless you encounter stack overflow errors.
- -t, --touch
-
Ignored for compatibility with GNU
make.
(Touching a file to make it
appear up-to-date is unnecessary when using
scons.)
- --taskmastertrace=file
-
Prints trace information to the specified
file
about how the internal Taskmaster object
evaluates and controls the order in which Nodes are built.
A file name of
-
may be used to specify the standard output.
- -tree=options
-
Prints a tree of the dependencies
after each top-level target is built.
This prints out some or all of the tree,
in various formats,
depending on the
options
specified:
- --tree=all
-
Print the entire dependency tree
after each top-level target is built.
This prints out the complete dependency tree,
including implicit dependencies and ignored dependencies.
- --tree=derived
-
Restricts the tree output to only derived (target) files,
not source files.
- --tree=status
-
Prints status information for each displayed node.
- --tree=prune
-
Prunes the tree to avoid repeating dependency information
for nodes that have already been displayed.
Any node that has already been displayed
will have its name printed in
[square brackets],
as an indication that the dependencies
for that node can be found by searching
for the relevant output higher up in the tree.
-
Multiple options may be specified,
separated by commas:
-
# Prints only derived files, with status information: scons --tree=derived,status # Prints all dependencies of target, with status information # and pruning dependencies of already-visited Nodes: scons --tree=all,prune,status target
-
- -u, --up, --search-up
-
Walks up the directory structure until an
SConstruct ,
Sconstruct
or
sconstruct
file is found, and uses that
as the top of the directory tree.
If no targets are specified on the command line,
only targets at or below the
current directory will be built.
- -U
-
Works exactly the same way as the
-u
option except for the way default targets are handled.
When this option is used and no targets are specified on the command line,
all default targets that are defined in the SConscript(s) in the current
directory are built, regardless of what directory the resultant targets end
up in.
- -v, --version
-
Print the
scons
version, copyright information,
list of authors, and any other relevant information.
Then exit.
- -w, --print-directory
-
Print a message containing the working directory before and
after other processing.
- --no-print-directory
-
Turn off -w, even if it was turned on implicitly.
- --warn=type, --warn=no-type
-
Enable or disable warnings.
type
specifies the type of warnings to be enabled or disabled:
- --warn=all, --warn=no-all
-
Enables or disables all warnings.
- --warn=cache-write-error, --warn=no-cache-write-error
-
Enables or disables warnings about errors trying to
write a copy of a built file to a specified
CacheDir().
These warnings are disabled by default.
- --warn=corrupt-sconsign, --warn=no-corrupt-sconsign
-
Enables or disables warnings about unfamiliar signature data in
.sconsign
files.
These warnings are enabled by default.
- --warn=dependency, --warn=no-dependency
-
Enables or disables warnings about dependencies.
These warnings are disabled by default.
- --warn=deprecated, --warn=no-deprecated
-
Enables or disables all warnings about use of
currently deprecated features.
These warnings are enabled by default.
Note that the
--warn=no-deprecated
option does not disable warnings about absolutely all deprecated features.
Warnings for some deprecated features that have already been through
several releases with deprecation warnings
may be mandatory for a release or two
before they are officially no longer supported by SCons.
Warnings for some specific deprecated features
may be enabled or disabled individually;
see below.
-
- --warn=deprecated-copy, --warn=no-deprecated-copy
-
Enables or disables warnings about use of the deprecated
env.Copy()
method.
- --warn=deprecated-source-signatures, --warn=no-deprecated-source-signatures
-
Enables or disables warnings about use of the deprecated
SourceSignatures()
function or
env.SourceSignatures()
method.
- --warn=deprecated-target-signatures, --warn=no-deprecated-target-signatures
- Enables or disables warnings about use of the deprecated TargetSignatures() function or env.TargetSignatures() method.
-
- --warn=duplicate-environment, --warn=no-duplicate-environment
-
Enables or disables warnings about attempts to specify a build
of a target with two different construction environments
that use the same action.
These warnings are enabled by default.
- --warn=fortran-cxx-mix, --warn=no-fortran-cxx-mix
-
Enables or disables the specific warning about linking
Fortran and C++ object files in a single executable,
which can yield unpredictable behavior with some compilers.
- --warn=future-deprecated, --warn=no-future-deprecated
-
Enables or disables warnings about features
that will be deprecated in the future.
These warnings are disabled by default.
Enabling this warning is especially
recommended for projects that redistribute
SCons configurations for other users to build,
so that the project can be warned as soon as possible
about to-be-deprecated features
that may require changes to the configuration.
- --warn=link, --warn=no-link
-
Enables or disables warnings about link steps.
- --warn=misleading-keywords, --warn=no-misleading-keywords
-
Enables or disables warnings about use of the misspelled keywords
targets
and
sources
when calling Builders.
(Note the last
s
characters, the correct spellings are
target
and
source.)
These warnings are enabled by default.
- --warn=missing-sconscript, --warn=no-missing-sconscript
-
Enables or disables warnings about missing SConscript files.
These warnings are enabled by default.
- --warn=no-md5-module, --warn=no-no-md5-module
-
Enables or disables warnings about the version of Python
not having an MD5 checksum module available.
These warnings are enabled by default.
- --warn=no-metaclass-support, --warn=no-no-metaclass-support
-
Enables or disables warnings about the version of Python
not supporting metaclasses when the
--debug=memoizer
option is used.
These warnings are enabled by default.
- --warn=no-object-count, --warn=no-no-object-count
-
Enables or disables warnings about the
--debug=object
feature not working when
scons
is run with the python
-O
option or from optimized Python (.pyo) modules.
- --warn=no-parallel-support, --warn=no-no-parallel-support
-
Enables or disables warnings about the version of Python
not being able to support parallel builds when the
-j
option is used.
These warnings are enabled by default.
- --warn=python-version, --warn=no-python-version
-
Enables or disables the warning about running
SCons with a deprecated version of Python.
These warnings are enabled by default.
- --warn=reserved-variable, --warn=no-reserved-variable
-
Enables or disables warnings about attempts to set the
reserved construction variable names
CHANGED_SOURCES,
CHANGED_TARGETS,
TARGET,
TARGETS,
SOURCE,
SOURCES,
UNCHANGED_SOURCES
or
UNCHANGED_TARGETS.
These warnings are disabled by default.
- --warn=stack-size, --warn=no-stack-size
-
Enables or disables warnings about requests to set the stack size
that could not be honored.
These warnings are enabled by default.
- -Y repository, --repository=repository, --srcdir=repository
-
Search the specified repository for any input and target
files not found in the local directory hierarchy. Multiple
-Y
options may be specified, in which case the
repositories are searched in the order specified.
CONFIGURATION FILE REFERENCE
Construction Environments
A construction environment is the basic means by which the SConscript files communicate build information to scons. A new construction environment is created using the Environment function:
-
env = Environment()
Variables, called construction variables, may be set in a construction environment either by specifying them as keywords when the object is created or by assigning them a value after the object is created:
-
env = Environment(FOO = 'foo') env['BAR'] = 'bar'
As a convenience, construction variables may also be set or modified by the parse_flags keyword argument, which applies the ParseFlags method (described below) to the argument value after all other processing is completed. This is useful either if the exact content of the flags is unknown (for example, read from a control file) or if the flags are distributed to a number of construction variables.
-
env = Environment(parse_flags = '-Iinclude -DEBUG -lm')
This example adds 'include' to CPPPATH, 'EBUG' to CPPDEFINES, and 'm' to LIBS.
By default, a new construction environment is initialized with a set of builder methods and construction variables that are appropriate for the current platform. An optional platform keyword argument may be used to specify that an environment should be initialized for a different platform:
-
env = Environment(platform = 'cygwin') env = Environment(platform = 'os2') env = Environment(platform = 'posix') env = Environment(platform = 'win32')
Specifying a platform initializes the appropriate construction variables in the environment to use and generate file names with prefixes and suffixes appropriate for the platform.
Note that the win32 platform adds the SystemDrive and SystemRoot variables from the user's external environment to the construction environment's ENV dictionary. This is so that any executed commands that use sockets to connect with other systems (such as fetching source files from external CVS repository specifications like :pserver:anonymous@cvs.sourceforge.net:/cvsroot/scons) will work on Windows systems.
The platform argument may be function or callable object, in which case the Environment() method will call the specified argument to update the new construction environment:
-
def my_platform(env): env['VAR'] = 'xyzzy' env = Environment(platform = my_platform)
Additionally, a specific set of tools with which to initialize the environment may be specified as an optional keyword argument:
-
env = Environment(tools = ['msvc', 'lex'])
Non-built-in tools may be specified using the toolpath argument:
-
env = Environment(tools = ['default', 'foo'], toolpath = ['tools'])
This looks for a tool specification in tools/foo.py (as well as using the ordinary default tools for the platform). foo.py should have two functions: generate(env, **kw) and exists(env). The generate() function modifies the passed-in environment to set up variables so that the tool can be executed; it may use any keyword arguments that the user supplies (see below) to vary its initialization. The exists() function should return a true value if the tool is available. Tools in the toolpath are used before any of the built-in ones. For example, adding gcc.py to the toolpath would override the built-in gcc tool. Also note that the toolpath is stored in the environment for use by later calls to Clone() and Tool() methods:
-
base = Environment(toolpath=['custom_path']) derived = base.Clone(tools=['custom_tool']) derived.CustomBuilder()
The elements of the tools list may also be functions or callable objects, in which case the Environment() method will call the specified elements to update the new construction environment:
-
def my_tool(env): env['XYZZY'] = 'xyzzy' env = Environment(tools = [my_tool])
The individual elements of the tools list may also themselves be two-element lists of the form (toolname, kw_dict). SCons searches for the toolname specification file as described above, and passes kw_dict, which must be a dictionary, as keyword arguments to the tool's generate function. The generate function can use the arguments to modify the tool's behavior by setting up the environment in different ways or otherwise changing its initialization.
-
# in tools/my_tool.py: def generate(env, **kw): # Sets MY_TOOL to the value of keyword argument 'arg1' or 1. env['MY_TOOL'] = kw.get('arg1', '1') def exists(env): return 1 # in SConstruct: env = Environment(tools = ['default', ('my_tool', {'arg1': 'abc'})], toolpath=['tools'])
The tool definition (i.e. my_tool()) can use the PLATFORM variable from the environment it receives to customize the tool for different platforms.
If no tool list is specified, then SCons will auto-detect the installed tools using the PATH variable in the ENV construction variable and the platform name when the Environment is constructed. Changing the PATH variable after the Environment is constructed will not cause the tools to be redetected.
SCons supports the following tool specifications out of the box:
-
386asm aixc++ aixcc aixf77 aixlink ar as bcc32 c++ cc cvf dmd dvipdf dvips f77 f90 f95 fortran g++ g77 gas gcc gfortran gnulink gs hpc++ hpcc hplink icc icl ifl ifort ilink ilink32 intelc jar javac javah latex lex link linkloc m4 masm midl mingw mslib mslink mssdk msvc msvs mwcc mwld nasm pdflatex pdftex qt rmic rpcgen sgiar sgic++ sgicc sgilink sunar sunc++ suncc sunf77 sunf90 sunf95 sunlink swig tar tex textfile tlib yacc zip
Additionally, there is a "tool" named default which configures the environment with a default set of tools for the current platform.
On posix and cygwin platforms the GNU tools (e.g. gcc) are preferred by SCons, on Windows the Microsoft tools (e.g. msvc) followed by MinGW are preferred by SCons, and in OS/2 the IBM tools (e.g. icc) are preferred by SCons.
Builder Methods
Build rules are specified by calling a construction environment's builder methods. The arguments to the builder methods are target (a list of targets to be built, usually file names) and source (a list of sources to be built, usually file names).
Because long lists of file names can lead to a lot of quoting, scons supplies a Split() global function and a same-named environment method that split a single string into a list, separated on strings of white-space characters. (These are similar to the split() member function of Python strings but work even if the input isn't a string.)
Like all Python arguments, the target and source arguments to a builder method can be specified either with or without the "target" and "source" keywords. When the keywords are omitted, the target is first, followed by the source. The following are equivalent examples of calling the Program builder method:
-
env.Program('bar', ['bar.c', 'foo.c']) env.Program('bar', Split('bar.c foo.c')) env.Program('bar', env.Split('bar.c foo.c')) env.Program(source = ['bar.c', 'foo.c'], target = 'bar') env.Program(target = 'bar', Split('bar.c foo.c')) env.Program(target = 'bar', env.Split('bar.c foo.c')) env.Program('bar', source = 'bar.c foo.c'.split())
Target and source file names that are not absolute path names (that is, do not begin with / on POSIX systems or \ on Windows systems, with or without an optional drive letter) are interpreted relative to the directory containing the SConscript file being read. An initial # (hash mark) on a path name means that the rest of the file name is interpreted relative to the directory containing the top-level SConstruct file, even if the # is followed by a directory separator character (slash or backslash).
Examples:
-
# The comments describing the targets that will be built # assume these calls are in a SConscript file in the # a subdirectory named "subdir". # Builds the program "subdir/foo" from "subdir/foo.c": env.Program('foo', 'foo.c') # Builds the program "/tmp/bar" from "subdir/bar.c": env.Program('/tmp/bar', 'bar.c') # An initial '#' or '#/' are equivalent; the following # calls build the programs "foo" and "bar" (in the # top-level SConstruct directory) from "subdir/foo.c" and # "subdir/bar.c", respectively: env.Program('#foo', 'foo.c') env.Program('#/bar', 'bar.c') # Builds the program "other/foo" (relative to the top-level # SConstruct directory) from "subdir/foo.c": env.Program('#other/foo', 'foo.c')
When the target shares the same base name as the source and only the suffix varies, and if the builder method has a suffix defined for the target file type, then the target argument may be omitted completely, and scons will deduce the target file name from the source file name. The following examples all build the executable program bar (on POSIX systems) or bar.exe (on Windows systems) from the bar.c source file:
-
env.Program(target = 'bar', source = 'bar.c') env.Program('bar', source = 'bar.c') env.Program(source = 'bar.c') env.Program('bar.c')
As a convenience, a srcdir keyword argument may be specified when calling a Builder. When specified, all source file strings that are not absolute paths will be interpreted relative to the specified srcdir. The following example will build the build/prog (or build/prog.exe on Windows) program from the files src/f1.c and src/f2.c:
-
env.Program('build/prog', ['f1.c', 'f2.c'], srcdir='src')
It is possible to override or add construction variables when calling a builder method by passing additional keyword arguments. These overridden or added variables will only be in effect when building the target, so they will not affect other parts of the build. For example, if you want to add additional libraries for just one program:
-
env.Program('hello', 'hello.c', LIBS=['gl', 'glut'])
or generate a shared library with a non-standard suffix:
-
env.SharedLibrary('word', 'word.cpp', SHLIBSUFFIX='.ocx', LIBSUFFIXES=['.ocx'])
(Note that both the $SHLIBSUFFIX and $LIBSUFFIXES variables must be set if you want SCons to search automatically for dependencies on the non-standard library names; see the descriptions of these variables, below, for more information.)
It is also possible to use the parse_flags keyword argument in an override:
-
env = Program('hello', 'hello.c', parse_flags = '-Iinclude -DEBUG -lm')
This example adds 'include' to CPPPATH, 'EBUG' to CPPDEFINES, and 'm' to LIBS.
Although the builder methods defined by scons are, in fact, methods of a construction environment object, they may also be called without an explicit environment:
-
Program('hello', 'hello.c') SharedLibrary('word', 'word.cpp')
In this case, the methods are called internally using a default construction environment that consists of the tools and values that scons has determined are appropriate for the local system.
Builder methods that can be called without an explicit environment may be called from custom Python modules that you import into an SConscript file by adding the following to the Python module:
-
from SCons.Script import *
All builder methods return a list-like object containing Nodes that represent the target or targets that will be built. A Node is an internal SCons object which represents build targets or sources.
The returned Node-list object can be passed to other builder methods as source(s) or passed to any SCons function or method where a filename would normally be accepted. For example, if it were necessary to add a specific -D flag when compiling one specific object file:
-
bar_obj_list = env.StaticObject('bar.c', CPPDEFINES='-DBAR') env.Program(source = ['foo.c', bar_obj_list, 'main.c'])
Using a Node in this way makes for a more portable build by avoiding having to specify a platform-specific object suffix when calling the Program() builder method.
Note that Builder calls will automatically "flatten" the source and target file lists, so it's all right to have the bar_obj list return by the StaticObject() call in the middle of the source file list. If you need to manipulate a list of lists returned by Builders directly using Python, you can either build the list by hand:
-
foo = Object('foo.c') bar = Object('bar.c') objects = ['begin.o'] + foo + ['middle.o'] + bar + ['end.o'] for object in objects: print str(object)
Or you can use the Flatten() function supplied by scons to create a list containing just the Nodes, which may be more convenient:
-
foo = Object('foo.c') bar = Object('bar.c') objects = Flatten(['begin.o', foo, 'middle.o', bar, 'end.o']) for object in objects: print str(object)
Note also that because Builder calls return a list-like object, not an actual Python list, you should not use the Python += operator to append Builder results to a Python list. Because the list and the object are different types, Python will not update the original list in place, but will instead create a new Node-list object containing the concatenation of the list elements and the Builder results. This will cause problems for any other Python variables in your SCons configuration that still hold on to a reference to the original list. Instead, use the Python .extend() method to make sure the list is updated in-place. Example:
-
object_files = [] # Do NOT use += as follows: # # object_files += Object('bar.c') # # It will not update the object_files list in place. # # Instead, use the .extend() method: object_files.extend(Object('bar.c'))
The path name for a Node's file may be used by passing the Node to the Python-builtin str() function:
-
bar_obj_list = env.StaticObject('bar.c', CPPDEFINES='-DBAR') print "The path to bar_obj is:", str(bar_obj_list[0])
Note again that because the Builder call returns a list, we have to access the first element in the list (bar_obj_list[0]) to get at the Node that actually represents the object file.
Builder calls support a chdir keyword argument that specifies that the Builder's action(s) should be executed after changing directory. If the chdir argument is a string or a directory Node, scons will change to the specified directory. If the chdir is not a string or Node and is non-zero, then scons will change to the target file's directory.
-
# scons will change to the "sub" subdirectory # before executing the "cp" command. env.Command('sub/dir/foo.out', 'sub/dir/foo.in', "cp dir/foo.in dir/foo.out", chdir='sub') # Because chdir is not a string, scons will change to the # target's directory ("sub/dir") before executing the # "cp" command. env.Command('sub/dir/foo.out', 'sub/dir/foo.in', "cp foo.in foo.out", chdir=1)
Note that scons will not automatically modify its expansion of construction variables like $TARGET and $SOURCE when using the chdir keyword argument--that is, the expanded file names will still be relative to the top-level SConstruct directory, and consequently incorrect relative to the chdir directory. If you use the chdir keyword argument, you will typically need to supply a different command line using expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the targets and source.
scons provides the following builder methods:
- CFile()
- env.CFile()
-
Builds a C source file given a lex (.l)
or yacc (.y) input file.
The suffix specified by the $CFILESUFFIX construction variable
(.c by default)
is automatically added to the target
if it is not already present.
Example:
-
# builds foo.c env.CFile(target = 'foo.c', source = 'foo.l') # builds bar.c env.CFile(target = 'bar', source = 'bar.y')
-
- CXXFile()
- env.CXXFile()
-
Builds a C++ source file given a lex (.ll)
or yacc (.yy)
input file.
The suffix specified by the $CXXFILESUFFIX construction variable
(.cc by default)
is automatically added to the target
if it is not already present.
Example:
-
# builds foo.cc env.CXXFile(target = 'foo.cc', source = 'foo.ll') # builds bar.cc env.CXXFile(target = 'bar', source = 'bar.yy')
-
- DVI()
- env.DVI()
-
Builds a .dvi file
from a .tex,
.ltx or .latex input file.
If the source file suffix is .tex,
scons
will examine the contents of the file;
if the string
\documentclass
or
\documentstyle
is found, the file is assumed to be a LaTeX file and
the target is built by invoking the $LATEXCOM command line;
otherwise, the $TEXCOM command line is used.
If the file is a LaTeX file,
the
DVI()
builder method will also examine the contents
of the
.aux
file and invoke the $BIBTEX command line
if the string
bibdata
is found,
start $MAKEINDEX to generate an index if a
.ind
file is found
and will examine the contents
.log
file and re-run the $LATEXCOM command
if the log file says it is necessary.
The suffix .dvi (hard-coded within TeX itself) is automatically added to the target if it is not already present. Examples:
-
# builds from aaa.tex env.DVI(target = 'aaa.dvi', source = 'aaa.tex') # builds bbb.dvi env.DVI(target = 'bbb', source = 'bbb.ltx') # builds from ccc.latex env.DVI(target = 'ccc.dvi', source = 'ccc.latex')
-
- Install()
- env.Install()
-
Installs one or more source files or directories
in the specified target,
which must be a directory.
The names of the specified source files or directories
remain the same within the destination directory.
-
env.Install('/usr/local/bin', source = ['foo', 'bar'])
-
- InstallAs()
- env.InstallAs()
-
Installs one or more source files or directories
to specific names,
allowing changing a file or directory name
as part of the installation.
It is an error if the
target
and
source
arguments list different numbers of files or directories.
-
env.InstallAs(target = '/usr/local/bin/foo', source = 'foo_debug') env.InstallAs(target = ['../lib/libfoo.a', '../lib/libbar.a'], source = ['libFOO.a', 'libBAR.a'])
-
- Jar()
- env.Jar()
-
Builds a Java archive (.jar) file
from the specified list of sources.
Any directories in the source list
will be searched for .class files).
Any .java files in the source list
will be compiled to .class files
by calling the Java() Builder.
If the $JARCHDIR value is set, the jar command will change to the specified directory using the -C option. If $JARCHDIR is not set explicitly, &SCons; will use the top of any subdirectory tree in which Java .class were built by the Java() Builder.
If the contents any of the source files begin with the string Manifest-Version, the file is assumed to be a manifest and is passed to the jar command with the m option set.
-
env.Jar(target = 'foo.jar', source = 'classes') env.Jar(target = 'bar.jar', source = ['bar1.java', 'bar2.java'])
-
- Java()
- env.Java()
-
Builds one or more Java class files.
The sources may be any combination of explicit
.java files,
or directory trees which will be scanned
for .java files.
SCons will parse each source .java file to find the classes (including inner classes) defined within that file, and from that figure out the target .class files that will be created. The class files will be placed underneath the specified target directory.
SCons will also search each Java file for the Java package name, which it assumes can be found on a line beginning with the string package in the first column; the resulting .class files will be placed in a directory reflecting the specified package name. For example, the file Foo.java defining a single public Foo class and containing a package name of sub.dir will generate a corresponding sub/dir/Foo.class class file.
Examples:
-
env.Java(target = 'classes', source = 'src') env.Java(target = 'classes', source = ['src1', 'src2']) env.Java(target = 'classes', source = ['File1.java', 'File2.java'])
-
-
Java source files can use the native encoding for the underlying OS.
Since SCons compiles in simple ASCII mode by default,
the compiler will generate warnings about unmappable characters,
which may lead to errors as the file is processed further.
In this case, the user must specify the LANG
environment variable to tell the compiler what encoding is used.
For portibility, it's best if the encoding is hard-coded
so that the compile will work if it is done on a system
with a different encoding.
-
env = Environment() env['ENV']['LANG'] = 'en_GB.UTF-8'
-
- JavaH()
- env.JavaH()
-
Builds C header and source files for
implementing Java native methods.
The target can be either a directory
in which the header files will be written,
or a header file name which
will contain all of the definitions.
The source can be the names of .class files,
the names of .java files
to be compiled into .class files
by calling the Java() builder method,
or the objects returned from the
Java()
builder method.
If the construction variable $JAVACLASSDIR is set, either in the environment or in the call to the JavaH() builder method itself, then the value of the variable will be stripped from the beginning of any .class file names.
Examples:
-
# builds java_native.h classes = env.Java(target = 'classdir', source = 'src') env.JavaH(target = 'java_native.h', source = classes) # builds include/package_foo.h and include/package_bar.h env.JavaH(target = 'include', source = ['package/foo.class', 'package/bar.class']) # builds export/foo.h and export/bar.h env.JavaH(target = 'export', source = ['classes/foo.class', 'classes/bar.class'], JAVACLASSDIR = 'classes')
-
- Library()
- env.Library()
-
A synonym for the
StaticLibrary()
builder method.
- LoadableModule()
- env.LoadableModule()
-
On most systems,
this is the same as
SharedLibrary().
On Mac OS X (Darwin) platforms,
this creates a loadable module bundle.
- M4()
- env.M4()
-
Builds an output file from an M4 input file.
This uses a default $M4FLAGS value of
-E,
which considers all warnings to be fatal
and stops on the first warning
when using the GNU version of m4.
Example:
-
env.M4(target = 'foo.c', source = 'foo.c.m4')
-
- Moc()
- env.Moc()
-
Builds an output file from a moc input file. Moc input files are either
header files or cxx files. This builder is only available after using the
tool 'qt'. See the $QTDIR variable for more information.
Example:
-
env.Moc('foo.h') # generates moc_foo.cc env.Moc('foo.cpp') # generates foo.moc
-
- MSVSProject()
- env.MSVSProject()
-
Builds a Microsoft Visual Studio project file,
and by default builds a solution file as well.
This builds a Visual Studio project file, based on the version of Visual Studio that is configured (either the latest installed version, or the version specified by $MSVS_VERSION in the Environment constructor). For Visual Studio 6, it will generate a .dsp file. For Visual Studio 7 (.NET) and later versions, it will generate a .vcproj file.
By default, this also generates a solution file for the specified project, a .dsw file for Visual Studio 6 or a .sln file for Visual Studio 7 (.NET). This behavior may be disabled by specifying auto_build_solution=0 when you call MSVSProject(), in which case you presumably want to build the solution file(s) by calling the MSVSSolution() Builder (see below).
The MSVSProject() builder takes several lists of filenames to be placed into the project file. These are currently limited to srcs, incs, localincs, resources, and misc. These are pretty self-explanatory, but it should be noted that these lists are added to the $SOURCES construction variable as strings, NOT as SCons File Nodes. This is because they represent file names to be added to the project file, not the source files used to build the project file.
The above filename lists are all optional, although at least one must be specified for the resulting project file to be non-empty.
In addition to the above lists of values, the following values may be specified:
target: The name of the target .dsp or .vcproj file. The correct suffix for the version of Visual Studio must be used, but the $MSVSPROJECTSUFFIX construction variable will be defined to the correct value (see example below).
variant: The name of this particular variant. For Visual Studio 7 projects, this can also be a list of variant names. These are typically things like "Debug" or "Release", but really can be anything you want. For Visual Studio 7 projects, they may also specify a target platform separated from the variant name by a | (vertical pipe) character: Debug|Xbox. The default target platform is Win32. Multiple calls to MSVSProject() with different variants are allowed; all variants will be added to the project file with their appropriate build targets and sources.
buildtarget: An optional string, node, or list of strings or nodes (one per build variant), to tell the Visual Studio debugger what output target to use in what build variant. The number of buildtarget entries must match the number of variant entries.
runfile: The name of the file that Visual Studio 7 and later will run and debug. This appears as the value of the Output field in the resutling Visual Studio project file. If this is not specified, the default is the same as the specified buildtarget value.
Note that because &SCons; always executes its build commands from the directory in which the SConstruct file is located, if you generate a project file in a different directory than the SConstruct directory, users will not be able to double-click on the file name in compilation error messages displayed in the Visual Studio console output window. This can be remedied by adding the Visual C/C++ /FC compiler option to the $CCFLAGS variable so that the compiler will print the full path name of any files that cause compilation errors.
Example usage:
-
barsrcs = ['bar.cpp'], barincs = ['bar.h'], barlocalincs = ['StdAfx.h'] barresources = ['bar.rc','resource.h'] barmisc = ['bar_readme.txt'] dll = env.SharedLibrary(target = 'bar.dll', source = barsrcs) env.MSVSProject(target = 'Bar' + env['MSVSPROJECTSUFFIX'], srcs = barsrcs, incs = barincs, localincs = barlocalincs, resources = barresources, misc = barmisc, buildtarget = dll, variant = 'Release')
-
- MSVSSolution()
- env.MSVSSolution()
-
Builds a Microsoft Visual Studio solution file.
This builds a Visual Studio solution file, based on the version of Visual Studio that is configured (either the latest installed version, or the version specified by $MSVS_VERSION in the construction environment). For Visual Studio 6, it will generate a .dsw file. For Visual Studio 7 (.NET), it will generate a .sln file.
The following values must be specified:
target: The name of the target .dsw or .sln file. The correct suffix for the version of Visual Studio must be used, but the value $MSVSSOLUTIONSUFFIX will be defined to the correct value (see example below).
variant: The name of this particular variant, or a list of variant names (the latter is only supported for MSVS 7 solutions). These are typically things like "Debug" or "Release", but really can be anything you want. For MSVS 7 they may also specify target platform, like this "Debug|Xbox". Default platform is Win32.
projects: A list of project file names, or Project nodes returned by calls to the MSVSProject() Builder, to be placed into the solution file. It should be noted that these file names are NOT added to the $SOURCES environment variable in form of files, but rather as strings. This is because they represent file names to be added to the solution file, not the source files used to build the solution file.
(NOTE: Currently only one project is supported per solution.)
Example Usage:
-
env.MSVSSolution(target = 'Bar' + env['MSVSSOLUTIONSUFFIX'], projects = ['bar' + env['MSVSPROJECTSUFFIX']], variant = 'Release')
-
- Object()
- env.Object()
-
A synonym for the
StaticObject()
builder method.
- Package()
- env.Package()
-
Builds software distribution packages.
Packages consist of files to install and packaging information.
The former may be specified with the source parameter and may be left out,
in which case the &FindInstalledFiles; function will collect
all files that have an Install() or InstallAs() Builder attached.
If the target is not specified
it will be deduced from additional information given to this Builder.
The packaging information is specified with the help of construction variables documented below. This information is called a tag to stress that some of them can also be attached to files with the &Tag; function. The mandatory ones will complain if they were not specified. They vary depending on chosen target packager.
The target packager may be selected with the "PACKAGETYPE" command line option or with the $PACKAGETYPE construction variable. Currently the following packagers available:
* msi - Microsoft Installer
* rpm - Redhat Package Manger
* ipkg - Itsy Package Management System
* tarbz2 - compressed tar
* targz - compressed tar
* zip - zip file
* src_tarbz2 - compressed tar source
* src_targz - compressed tar source
* src_zip - zip file sourceAn updated list is always available under the "package_type" option when running "scons --help" on a project that has packaging activated.
-
env = Environment(tools=['default', 'packaging']) env.Install('/bin/', 'my_program') env.Package( NAME = 'foo', VERSION = '1.2.3', PACKAGEVERSION = 0, PACKAGETYPE = 'rpm', LICENSE = 'gpl', SUMMARY = 'balalalalal', DESCRIPTION = 'this should be really really long', X_RPM_GROUP = 'Application/fu', SOURCE_URL = 'http://foo.org/foo-1.2.3.tar.gz' )
-
- PCH()
- env.PCH()
-
Builds a Microsoft Visual C++ precompiled header.
Calling this builder method
returns a list of two targets: the PCH as the first element, and the object
file as the second element. Normally the object file is ignored.
This builder method is only
provided when Microsoft Visual C++ is being used as the compiler.
The PCH builder method is generally used in
conjuction with the PCH construction variable to force object files to use
the precompiled header:
-
env['PCH'] = env.PCH('StdAfx.cpp')[0]
-
- PDF()
- env.PDF()
-
Builds a .pdf file
from a .dvi input file
(or, by extension, a .tex,
.ltx,
or
.latex input file).
The suffix specified by the $PDFSUFFIX construction variable
(.pdf by default)
is added automatically to the target
if it is not already present. Example:
-
# builds from aaa.tex env.PDF(target = 'aaa.pdf', source = 'aaa.tex') # builds bbb.pdf from bbb.dvi env.PDF(target = 'bbb', source = 'bbb.dvi')
-
- PostScript()
- env.PostScript()
-
Builds a .ps file
from a .dvi input file
(or, by extension, a .tex,
.ltx,
or
.latex input file).
The suffix specified by the $PSSUFFIX construction variable
(.ps by default)
is added automatically to the target
if it is not already present. Example:
-
# builds from aaa.tex env.PostScript(target = 'aaa.ps', source = 'aaa.tex') # builds bbb.ps from bbb.dvi env.PostScript(target = 'bbb', source = 'bbb.dvi')
-
- Program()
- env.Program()
-
Builds an executable given one or more object files
or C, C++, D, or Fortran source files.
If any C, C++, D or Fortran source files are specified,
then they will be automatically
compiled to object files using the
Object()
builder method;
see that builder method's description for
a list of legal source file suffixes
and how they are interpreted.
The target executable file prefix
(specified by the $PROGPREFIX construction variable; nothing by default)
and suffix
(specified by the $PROGSUFFIX construction variable;
by default, .exe on Windows systems,
nothing on POSIX systems)
are automatically added to the target if not already present.
Example:
-
env.Program(target = 'foo', source = ['foo.o', 'bar.c', 'baz.f'])
-
- RES()
- env.RES()
-
Builds a Microsoft Visual C++ resource file.
This builder method is only provided
when Microsoft Visual C++ or MinGW is being used as the compiler. The
.res
(or
.o
for MinGW) suffix is added to the target name if no other suffix is given.
The source
file is scanned for implicit dependencies as though it were a C file.
Example:
-
env.RES('resource.rc')
-
- RMIC()
- env.RMIC()
-
Builds stub and skeleton class files
for remote objects
from Java .class files.
The target is a directory
relative to which the stub
and skeleton class files will be written.
The source can be the names of .class files,
or the objects return from the
Java()
builder method.
If the construction variable $JAVACLASSDIR is set, either in the environment or in the call to the RMIC() builder method itself, then the value of the variable will be stripped from the beginning of any .class file names.
-
classes = env.Java(target = 'classdir', source = 'src') env.RMIC(target = 'outdir1', source = classes) env.RMIC(target = 'outdir2', source = ['package/foo.class', 'package/bar.class']) env.RMIC(target = 'outdir3', source = ['classes/foo.class', 'classes/bar.class'], JAVACLASSDIR = 'classes')
-
- RPCGenClient()
- env.RPCGenClient()
-
Generates an RPC client stub (_clnt.c) file
from a specified RPC (.x) source file.
Because rpcgen only builds output files
in the local directory,
the command will be executed
in the source file's directory by default.
-
# Builds src/rpcif_clnt.c env.RPCGenClient('src/rpcif.x')
-
- RPCGenHeader()
- env.RPCGenHeader()
-
Generates an RPC header (.h) file
from a specified RPC (.x) source file.
Because rpcgen only builds output files
in the local directory,
the command will be executed
in the source file's directory by default.
-
# Builds src/rpcif.h env.RPCGenHeader('src/rpcif.x')
-
- RPCGenService()
- env.RPCGenService()
-
Generates an RPC server-skeleton (_svc.c) file
from a specified RPC (.x) source file.
Because rpcgen only builds output files
in the local directory,
the command will be executed
in the source file's directory by default.
-
# Builds src/rpcif_svc.c env.RPCGenClient('src/rpcif.x')
-
- RPCGenXDR()
- env.RPCGenXDR()
-
Generates an RPC XDR routine (_xdr.c) file
from a specified RPC (.x) source file.
Because rpcgen only builds output files
in the local directory,
the command will be executed
in the source file's directory by default.
-
# Builds src/rpcif_xdr.c env.RPCGenClient('src/rpcif.x')
-
- SharedLibrary()
- env.SharedLibrary()
-
Builds a shared library
(.so on a POSIX system,
.dll on Windows)
given one or more object files
or C, C++, D or Fortran source files.
If any source files are given,
then they will be automatically
compiled to object files.
The static library prefix and suffix (if any)
are automatically added to the target.
The target library file prefix
(specified by the $SHLIBPREFIX construction variable;
by default, lib on POSIX systems,
nothing on Windows systems)
and suffix
(specified by the $SHLIBSUFFIX construction variable;
by default, .dll on Windows systems,
.so on POSIX systems)
are automatically added to the target if not already present.
Example:
-
env.SharedLibrary(target = 'bar', source = ['bar.c', 'foo.o'])
-
-
On Windows systems, the
SharedLibrary()
builder method will always build an import
(.lib) library
in addition to the shared (.dll) library,
adding a .lib library with the same basename
if there is not already a .lib file explicitly
listed in the targets.
Any object files listed in the source must have been built for a shared library (that is, using the SharedObject() builder method). scons will raise an error if there is any mismatch.
On some platforms, there is a distinction between a shared library (loaded automatically by the system to resolve external references) and a loadable module (explicitly loaded by user action). For maximum portability, use the LoadableModule() builder for the latter.
On Windows systems, specifying register=1 will cause the .dll to be registered after it is built using REGSVR32. The command that is run ("regsvr32" by default) is determined by $REGSVR construction variable, and the flags passed are determined by $REGSVRFLAGS. By default, $REGSVRFLAGS includes the /s option, to prevent dialogs from popping up and requiring user attention when it is run. If you change $REGSVRFLAGS, be sure to include the /s option. For example,
-
env.SharedLibrary(target = 'bar', source = ['bar.cxx', 'foo.obj'], register=1)
-
-
will register bar.dll as a COM object
when it is done linking it.
- SharedObject()
- env.SharedObject()
-
Builds an object file for
inclusion in a shared library.
Source files must have one of the same set of extensions
specified above for the
StaticObject()
builder method.
On some platforms building a shared object requires additional
compiler option
(e.g. -fPIC for gcc)
in addition to those needed to build a
normal (static) object, but on some platforms there is no difference between a
shared object and a normal (static) one. When there is a difference, SCons
will only allow shared objects to be linked into a shared library, and will
use a different suffix for shared objects. On platforms where there is no
difference, SCons will allow both normal (static)
and shared objects to be linked into a
shared library, and will use the same suffix for shared and normal
(static) objects.
The target object file prefix
(specified by the $SHOBJPREFIX construction variable;
by default, the same as $OBJPREFIX)
and suffix
(specified by the $SHOBJSUFFIX construction variable)
are automatically added to the target if not already present.
Examples:
-
env.SharedObject(target = 'ddd', source = 'ddd.c') env.SharedObject(target = 'eee.o', source = 'eee.cpp') env.SharedObject(target = 'fff.obj', source = 'fff.for')
-
-
Note that the source files will be scanned
according to the suffix mappings in the
SourceFileScanner
object.
See the section "Scanner Objects,"
below, for more information.
- StaticLibrary()
- env.StaticLibrary()
-
Builds a static library given one or more object files
or C, C++, D or Fortran source files.
If any source files are given,
then they will be automatically
compiled to object files.
The static library prefix and suffix (if any)
are automatically added to the target.
The target library file prefix
(specified by the $LIBPREFIX construction variable;
by default, lib on POSIX systems,
nothing on Windows systems)
and suffix
(specified by the $LIBSUFFIX construction variable;
by default, .lib on Windows systems,
.a on POSIX systems)
are automatically added to the target if not already present.
Example:
-
env.StaticLibrary(target = 'bar', source = ['bar.c', 'foo.o'])
-
-
Any object files listed in the
source
must have been built for a static library
(that is, using the
StaticObject()
builder method).
scons
will raise an error if there is any mismatch.
- StaticObject()
- env.StaticObject()
-
Builds a static object file
from one or more C, C++, D, or Fortran source files.
Source files must have one of the following extensions:
-
.asm assembly language file .ASM assembly language file .c C file .C Windows: C file POSIX: C++ file .cc C++ file .cpp C++ file .cxx C++ file .cxx C++ file .c++ C++ file .C++ C++ file .d D file .f Fortran file .F Windows: Fortran file POSIX: Fortran file + C pre-processor .for Fortran file .FOR Fortran file .fpp Fortran file + C pre-processor .FPP Fortran file + C pre-processor .m Object C file .mm Object C++ file .s assembly language file .S Windows: assembly language file ARM: CodeSourcery Sourcery Lite .sx assembly language file + C pre-processor POSIX: assembly language file + C pre-processor .spp assembly language file + C pre-processor .SPP assembly language file + C pre-processor
-
-
The target object file prefix
(specified by the $OBJPREFIX construction variable; nothing by default)
and suffix
(specified by the $OBJSUFFIX construction variable;
.obj on Windows systems,
.o on POSIX systems)
are automatically added to the target if not already present.
Examples:
-
env.StaticObject(target = 'aaa', source = 'aaa.c') env.StaticObject(target = 'bbb.o', source = 'bbb.c++') env.StaticObject(target = 'ccc.obj', source = 'ccc.f')
-
-
Note that the source files will be scanned
according to the suffix mappings in
SourceFileScanner
object.
See the section "Scanner Objects,"
below, for more information.
- Substfile()
- env.Substfile()
-
The Substfile() builder generates a single text file
by concatenating the source files.
Nested lists of sources are flattened.
$LINESEPARATOR is used to separate the source files;
see the description of Textfile() for details.
If a single source file is present with an .in suffix, the suffix is stripped and the remainder is used as the default target name.
The prefix and suffix specified by the $SUBSTFILEPREFIX and $SUBSTFILESUFFIX construction variables (the null string by default in both cases) are automatically added to the target if they are not already present.
If a construction variable named $SUBST_DICT is present, it may be either a Python dictionary or a sequence of (key,value) tuples. If the former, the dictionary is converted into a list of tuples in an arbitrary order, so if one key is a prefix of another key or if one substitution could be further expanded by another subsitition, it is unpredictible whether the expansion will occur.
Any occurences in the source of a key are replaced by the corresponding value, which may be a Python callable function or a string. If a value is a function, it is first called (with no arguments) to produce a string. The string is subst-expanded and the result replaces the key.
-
env = Environment(tools = ['default', 'textfile']) env['prefix'] = '/usr/bin' script_dict = {'@prefix@': '/bin', @exec_prefix@: '$prefix'} env.Substfile('script.in', SUBST_DICT = script_dict) conf_dict = {'%VERSION%': '1.2.3', '%BASE%': 'MyProg'} env.Substfile('config.h.in', conf_dict, SUBST_DICT = conf_dict) # UNPREDICTABLE - one key is a prefix of another bad_foo = {'$foo': '$foo', '$foobar': '$foobar'} env.Substfile('foo.in', SUBST_DICT = bad_foo) # PREDICTABLE - keys are applied longest first good_foo = [('$foobar', '$foobar'), ('$foo', '$foo')] env.Substfile('foo.in', SUBST_DICT = good_foo) # UNPREDICTABLE - one substitution could be futher expanded bad_bar = {'@bar@': '@soap@', '@soap@': 'lye'} env.Substfile('bar.in', SUBST_DICT = bad_bar) # PREDICTABLE - substitutions are expanded in order good_bar = (('@bar@', '@soap@'), ('@soap@', 'lye')) env.Substfile('bar.in', SUBST_DICT = good_bar) # the SUBST_DICT may be in common (and not an override) substutions = {} subst = Environment(tools = ['textfile', SUBST_DICT = substitutions) substitutions['@foo@'] = 'foo' subst['SUBST_DICT']['@bar@'] = 'bar' subst.Substfile('pgm1.c', [Value('#include "@foo@.h"'), Value('#include "@bar@.h"'), "common.in", "pgm1.in" ]) subst.Substfile('pgm2.c', [Value('#include "@foo@.h"'), Value('#include "@bar@.h"'), "common.in", "pgm2.in" ])
-
- Tar()
- env.Tar()
-
Builds a tar archive of the specified files
and/or directories.
Unlike most builder methods,
the
Tar()
builder method may be called multiple times
for a given target;
each additional call
adds to the list of entries
that will be built into the archive.
Any source directories will
be scanned for changes to
any on-disk files,
regardless of whether or not
scons
knows about them from other Builder or function calls.
-
env.Tar('src.tar', 'src') # Create the stuff.tar file. env.Tar('stuff', ['subdir1', 'subdir2']) # Also add "another" to the stuff.tar file. env.Tar('stuff', 'another') # Set TARFLAGS to create a gzip-filtered archive. env = Environment(TARFLAGS = '-c -z') env.Tar('foo.tar.gz', 'foo') # Also set the suffix to .tgz. env = Environment(TARFLAGS = '-c -z', TARSUFFIX = '.tgz') env.Tar('foo')
-
- Textfile()
- env.Textfile()
-
The Textfile() builder generates a single text file.
The source strings constitute the lines;
nested lists of sources are flattened.
$LINESEPARATOR is used to separate the strings.
If present, the $SUBST_DICT construction variable is used to modify the strings before they are written; see the Substfile() description for details.
The prefix and suffix specified by the $TEXTFILEPREFIX and $TEXTFILESUFFIX construction variables (the null string and .txt by default, respectively) are automatically added to the target if they are not already present. Examples:
-
# builds/writes foo.txt env.Textfile(target = 'foo.txt', source = ['Goethe', 42, 'Schiller']) # builds/writes bar.txt env.Textfile(target = 'bar', source = ['lalala', 'tanteratei'], LINESEPARATOR='|*') # nested lists are flattened automatically env.Textfile(target = 'blob', source = ['lalala', ['Goethe', 42 'Schiller'], 'tanteratei']) # files may be used as input by wraping them in File() env.Textfile(target = 'concat', # concatenate files with a marker between source = [File('concat1'), File('concat2')], LINESEPARATOR = '====================
') Results are: foo.txt ....8<---- Goethe 42 Schiller ....8<---- (no linefeed at the end) bar.txt: ....8<---- lalala|*tanteratei ....8<---- (no linefeed at the end) blob.txt ....8<---- lalala Goethe 42 Schiller tanteratei ....8<---- (no linefeed at the end)
-
- TypeLibrary()
- env.TypeLibrary()
-
Builds a Windows type library (.tlb)
file from an input IDL file (.idl).
In addition, it will build the associated inteface stub and
proxy source files,
naming them according to the base name of the .idl file.
For example,
-
env.TypeLibrary(source="foo.idl")
-
-
Will create foo.tlb,
foo.h,
foo_i.c,
foo_p.c
and
foo_data.c
files.
- Uic()
- env.Uic()
-
Builds a header file, an implementation file and a moc file from an ui file.
and returns the corresponding nodes in the above order.
This builder is only available after using the tool 'qt'. Note: you can
specify .ui files directly as source
files to the Program(),
Library() and SharedLibrary() builders
without using this builder. Using this builder lets you override the standard
naming conventions (be careful: prefixes are always prepended to names of
built files; if you don't want prefixes, you may set them to ``).
See the $QTDIR variable for more information.
Example:
-
env.Uic('foo.ui') # -> ['foo.h', 'uic_foo.cc', 'moc_foo.cc'] env.Uic(target = Split('include/foo.h gen/uicfoo.cc gen/mocfoo.cc'), source = 'foo.ui') # -> ['include/foo.h', 'gen/uicfoo.cc', 'gen/mocfoo.cc']
-
- Zip()
- env.Zip()
-
Builds a zip archive of the specified files
and/or directories.
Unlike most builder methods,
the
Zip()
builder method may be called multiple times
for a given target;
each additional call
adds to the list of entries
that will be built into the archive.
Any source directories will
be scanned for changes to
any on-disk files,
regardless of whether or not
scons
knows about them from other Builder or function calls.
-
env.Zip('src.zip', 'src') # Create the stuff.zip file. env.Zip('stuff', ['subdir1', 'subdir2']) # Also add "another" to the stuff.tar file. env.Zip('stuff', 'another')
All targets of builder methods automatically depend on their sources. An explicit dependency can be specified using the Depends method of a construction environment (see below).
In addition, scons automatically scans source files for various programming languages, so the dependencies do not need to be specified explicitly. By default, SCons can C source files, C++ source files, Fortran source files with .F (POSIX systems only), .fpp, or .FPP file extensions, and assembly language files with .S (POSIX systems only), .spp, or .SPP files extensions for C preprocessor dependencies. SCons also has default support for scanning D source files, You can also write your own Scanners to add support for additional source file types. These can be added to the default Scanner object used by the Object(), StaticObject(), and SharedObject() Builders by adding them to the SourceFileScanner object. See the section "Scanner Objects," below, for more information about defining your own Scanner objects and using the SourceFileScanner object.
-
Methods and Functions to Do Things
In addition to Builder methods, scons provides a number of other construction environment methods and global functions to manipulate the build configuration.Usually, a construction environment method and global function with the same name both exist so that you don't have to remember whether to a specific bit of functionality must be called with or without a construction environment. In the following list, if you call something as a global function it looks like:
-
Function(arguments)
-
env.Function(arguments)
Global functions may be called from custom Python modules that you import into an SConscript file by adding the following to the Python module:
-
from SCons.Script import *
Except where otherwise noted, the same-named construction environment method and global function provide the exact same functionality. The only difference is that, where appropriate, calling the functionality through a construction environment will substitute construction variables into any supplied strings. For example:
-
env = Environment(FOO = 'foo') Default('$FOO') env.Default('$FOO')
In the above example, the first call to the global Default() function will actually add a target named $FOO to the list of default targets, while the second call to the env.Default() construction environment method will expand the value and add a target named foo to the list of default targets. For more on construction variable expansion, see the next section on construction variables.
Construction environment methods and global functions supported by scons include:
- Action(action, [cmd/str/fun, [var, ...]] [option=value, ...])
- env.Action(action, [cmd/str/fun, [var, ...]] [option=value, ...])
-
Creates an Action object for
the specified
action.
See the section "Action Objects,"
below, for a complete explanation of the arguments and behavior.
Note that the env.Action() form of the invocation will expand construction variables in any argument strings, including the action argument, at the time it is called using the construction variables in the env construction environment through which env.Action() was called. The Action() form delays all variable expansion until the Action object is actually used.
- AddMethod(object,function, [name])
- env.AddMethod(function, [name])
-
When called with the
AddMethod()
form,
adds the specified
function
to the specified
object
as the specified method
name.
When called with the
env.AddMethod()
form,
adds the specified
function
to the construction environment
env
as the specified method
name.
In both cases, if
name
is omitted or
None,
the name of the
specified
function
itself is used for the method name.
Examples:
-
# Note that the first argument to the function to # be attached as a method must be the object through # which the method will be called; the Python # convention is to call it 'self'. def my_method(self, arg): print "my_method() got", arg # Use the global AddMethod() function to add a method # to the Environment class. This AddMethod(Environment, my_method) env = Environment() env.my_method('arg') # Add the function as a method, using the function # name for the method call. env = Environment() env.AddMethod(my_method, 'other_method_name') env.other_method_name('another arg')
-
- AddOption(arguments)
-
This function adds a new command-line option to be recognized.
The specified
arguments
are the same as supported by the standard Python
optparse.add_option()
method (with a few additional capabilities noted below);
see the documentation for
optparse
for a thorough discussion of its option-processing capabities.
In addition to the arguments and values supported by the optparse.add_option () method, the SCons AddOption() function allows you to set the nargs keyword value to '?' (a string with just the question mark) to indicate that the specified long option(s) take(s) an optional argument. When nargs = '?' is passed to the AddOption() function, the const keyword argument may be used to supply the "default" value that should be used when the option is specified on the command line without an explicit argument.
If no default= keyword argument is supplied when calling AddOption(), the option will have a default value of None.
Once a new command-line option has been added with AddOption(), the option value may be accessed using GetOption() or env.GetOption().
Any specified help= strings for the new option(s) will be displayed by the -H or -h options (the latter only if no other help text is specified in the SConscript files). The help text for the local options specified by AddOption() will appear below the SCons options themselves, under a separate Local Options heading. The options will appear in the help text in the order in which the AddOption() calls occur.
Example:
-
AddOption('--prefix', dest='prefix', nargs=1, type='string', action='store', metavar='DIR', help='installation prefix') env = Environment(PREFIX = GetOption('prefix'))
-
- AddPostAction(target, action)
- env.AddPostAction(target, action)
-
Arranges for the specified
action
to be performed
after the specified
target
has been built.
The specified action(s) may be
an Action object, or anything that
can be converted into an Action object
(see below).
When multiple targets are supplied, the action may be called multiple times, once after each action that generates one or more targets in the list.
- AddPreAction(target, action)
- env.AddPreAction(target, action)
-
Arranges for the specified
action
to be performed
before the specified
target
is built.
The specified action(s) may be
an Action object, or anything that
can be converted into an Action object
(see below).
When multiple targets are specified, the action(s) may be called multiple times, once before each action that generates one or more targets in the list.
Note that if any of the targets are built in multiple steps, the action will be invoked just before the "final" action that specifically generates the specified target(s). For example, when building an executable program from a specified source .c file via an intermediate object file:
-
foo = Program('foo.c') AddPreAction(foo, 'pre_action')
The specified pre_action would be executed before scons calls the link command that actually generates the executable program binary foo, not before compiling the foo.c file into an object file.
-
- Alias(alias, [targets, [action]])
- env.Alias(alias, [targets, [action]])
-
Creates one or more phony targets that
expand to one or more other targets.
An optional
action
(command)
or list of actions
can be specified that will be executed
whenever the any of the alias targets are out-of-date.
Returns the Node object representing the alias,
which exists outside of any file system.
This Node object, or the alias name,
may be used as a dependency of any other target,
including another alias.
Alias
can be called multiple times for the same
alias to add additional targets to the alias,
or additional actions to the list for this alias.
Examples:
-
Alias('install') Alias('install', '/usr/bin') Alias(['install', 'install-lib'], '/usr/local/lib') env.Alias('install', ['/usr/local/bin', '/usr/local/lib']) env.Alias('install', ['/usr/local/man']) env.Alias('update', ['file1', 'file2'], "update_database $SOURCES")
-
- AllowSubstExceptions([exception, ...])
-
Specifies the exceptions that will be allowed
when expanding construction variables.
By default,
any construction variable expansions that generate a
NameError
or
IndexError
exception will expand to a
''
(a null string) and not cause scons to fail.
All exceptions not in the specified list
will generate an error message
and terminate processing.
If AllowSubstExceptions is called multiple times, each call completely overwrites the previous list of allowed exceptions.
Example:
-
# Requires that all construction variable names exist. # (You may wish to do this if you want to enforce strictly # that all construction variables must be defined before use.) AllowSubstExceptions() # Also allow a string containing a zero-division expansion # like '${1 / 0}' to evalute to ''. AllowSubstExceptions(IndexError, NameError, ZeroDivisionError)
-
- AlwaysBuild(target, ...)
- env.AlwaysBuild(target, ...)
-
Marks each given
target
so that it is always assumed to be out of date,
and will always be rebuilt if needed.
Note, however, that
AlwaysBuild()
does not add its target(s) to the default target list,
so the targets will only be built
if they are specified on the command line,
or are a dependent of a target specified on the command line--but
they will
always
be built if so specified.
Multiple targets can be passed in to a single call to
AlwaysBuild().
- env.Append(key=val, [...])
-
Appends the specified keyword arguments
to the end of construction variables in the environment.
If the Environment does not have
the specified construction variable,
it is simply added to the environment.
If the values of the construction variable
and the keyword argument are the same type,
then the two values will be simply added together.
Otherwise, the construction variable
and the value of the keyword argument
are both coerced to lists,
and the lists are added together.
(See also the Prepend method, below.)
Example:
-
env.Append(CCFLAGS = ' -g', FOO = ['foo.yyy'])
-
- env.AppendENVPath(name, newpath, [envname, sep, delete_existing])
-
This appends new path elements to the given path in the
specified external environment
(ENV
by default).
This will only add
any particular path once (leaving the last one it encounters and
ignoring the rest, to preserve path order),
and to help assure this,
will normalize all paths (using
os.path.normpath
and
os.path.normcase).
This can also handle the
case where the given old path variable is a list instead of a
string, in which case a list will be returned instead of a string.
If delete_existing is 0, then adding a path that already exists will not move it to the end; it will stay where it is in the list.
Example:
-
print 'before:',env['ENV']['INCLUDE'] include_path = '/foo/bar:/foo' env.AppendENVPath('INCLUDE', include_path) print 'after:',env['ENV']['INCLUDE'] yields: before: /foo:/biz after: /biz:/foo/bar:/foo
-
- env.AppendUnique(key=val, [...], delete_existing=0)
-
Appends the specified keyword arguments
to the end of construction variables in the environment.
If the Environment does not have
the specified construction variable,
it is simply added to the environment.
If the construction variable being appended to is a list,
then any value(s) that already exist in the
construction variable will
not
be added again to the list.
However, if delete_existing is 1,
existing matching values are removed first, so
existing values in the arg list move to the end of the list.
Example:
-
env.AppendUnique(CCFLAGS = '-g', FOO = ['foo.yyy'])
-
- env.BitKeeper()
-
A factory function that
returns a Builder object
to be used to fetch source files
using BitKeeper.
The returned Builder
is intended to be passed to the
SourceCode
function.
This function is deprecated. For details, see the entry for the SourceCode function.
Example:
-
env.SourceCode('.', env.BitKeeper())
-
- BuildDir(build_dir, src_dir, [duplicate])
- env.BuildDir(build_dir, src_dir, [duplicate])
-
Deprecated synonyms for
VariantDir()
and
env.VariantDir().
The
build_dir
argument becomes the
variant_dir
argument of
VariantDir()
or
env.VariantDir().
- Builder(action, [arguments])
- env.Builder(action, [arguments])
-
Creates a Builder object for
the specified
action.
See the section "Builder Objects,"
below, for a complete explanation of the arguments and behavior.
Note that the env.Builder() form of the invocation will expand construction variables in any arguments strings, including the action argument, at the time it is called using the construction variables in the env construction environment through which env.Builder() was called. The Builder() form delays all variable expansion until after the Builder object is actually called.
- CacheDir(cache_dir)
- env.CacheDir(cache_dir)
-
Specifies that
scons
will maintain a cache of derived files in
cache_dir .
The derived files in the cache will be shared
among all the builds using the same
CacheDir()
call.
Specifying a
cache_dir
of
None
disables derived file caching.
Calling env.CacheDir() will only affect targets built through the specified construction environment. Calling CacheDir() sets a global default that will be used by all targets built through construction environments that do not have an env.CacheDir() specified.
When a CacheDir() is being used and scons finds a derived file that needs to be rebuilt, it will first look in the cache to see if a derived file has already been built from identical input files and an identical build action (as incorporated into the MD5 build signature). If so, scons will retrieve the file from the cache. If the derived file is not present in the cache, scons will rebuild it and then place a copy of the built file in the cache (identified by its MD5 build signature), so that it may be retrieved by other builds that need to build the same derived file from identical inputs.
Use of a specified CacheDir() may be disabled for any invocation by using the --cache-disable option.
If the --cache-force option is used, scons will place a copy of all derived files in the cache, even if they already existed and were not built by this invocation. This is useful to populate a cache the first time CacheDir() is added to a build, or after using the --cache-disable option.
When using CacheDir(), scons will report, "Retrieved `file' from cache," unless the --cache-show option is being used. When the --cache-show option is used, scons will print the action that would have been used to build the file, without any indication that the file was actually retrieved from the cache. This is useful to generate build logs that are equivalent regardless of whether a given derived file has been built in-place or retrieved from the cache.
The NoCache() method can be used to disable caching of specific files. This can be useful if inputs and/or outputs of some tool are impossible to predict or prohibitively large.
- Clean(targets, files_or_dirs)
- env.Clean(targets, files_or_dirs)
-
This specifies a list of files or directories which should be removed
whenever the targets are specified with the
-c
command line option.
The specified targets may be a list
or an individual target.
Multiple calls to
Clean()
are legal,
and create new targets or add files and directories to the
clean list for the specified targets.
Multiple files or directories should be specified either as separate arguments to the Clean() method, or as a list. Clean() will also accept the return value of any of the construction environment Builder methods. Examples:
The related NoClean() function overrides calling Clean() for the same target, and any targets passed to both functions will not be removed by the -c option.
Examples:
-
Clean('foo', ['bar', 'baz']) Clean('dist', env.Program('hello', 'hello.c')) Clean(['foo', 'bar'], 'something_else_to_clean')
In this example, installing the project creates a subdirectory for the documentation. This statement causes the subdirectory to be removed if the project is deinstalled.
-
Clean(docdir, os.path.join(docdir, projectname))
-
- Command(target, source, action, [key=val, ...])
- env.Command(target, source, action, [key=val, ...])
-
Executes a specific action
(or list of actions)
to build a target file or files.
This is more convenient
than defining a separate Builder object
for a single special-case build.
As a special case, the source_scanner keyword argument can be used to specify a Scanner object that will be used to scan the sources. (The global DirScanner object can be used if any of the sources will be directories that must be scanned on-disk for changes to files that aren't already specified in other Builder of function calls.)
Any other keyword arguments specified override any same-named existing construction variables.
An action can be an external command, specified as a string, or a callable Python object; see "Action Objects," below, for more complete information. Also note that a string specifying an external command may be preceded by an @ (at-sign) to suppress printing the command in question, or by a - (hyphen) to ignore the exit status of the external command.
Examples:
-
env.Command('foo.out', 'foo.in', "$FOO_BUILD < $SOURCES > $TARGET") env.Command('bar.out', 'bar.in', ["rm -f $TARGET", "$BAR_BUILD < $SOURCES > $TARGET"], ENV = {'PATH' : '/usr/local/bin/'}) def rename(env, target, source): import os os.rename('.tmp', str(target[0])) env.Command('baz.out', 'baz.in', ["$BAZ_BUILD < $SOURCES > .tmp", rename ])
-
-
Note that the
Command()
function will usually assume, by default,
that the specified targets and/or sources are Files,
if no other part of the configuration
identifies what type of entry it is.
If necessary, you can explicitly specify
that targets or source nodes should
be treated as directoriese
by using the
Dir()
or
env.Dir()
functions.
Examples:
-
env.Command('ddd.list', Dir('ddd'), 'ls -l $SOURCE > $TARGET') env['DISTDIR'] = 'destination/directory' env.Command(env.Dir('$DISTDIR')), None, make_distdir)
-
-
(Also note that SCons will usually
automatically create any directory necessary to hold a target file,
so you normally don't need to create directories by hand.)
- Configure(env, [custom_tests, conf_dir, log_file, config_h])
- env.Configure([custom_tests, conf_dir, log_file, config_h])
-
Creates a Configure object for integrated
functionality similar to GNU autoconf.
See the section "Configure Contexts,"
below, for a complete explanation of the arguments and behavior.
- env.Clone([key=val, ...])
-
Return a separate copy of a construction environment.
If there are any keyword arguments specified,
they are added to the returned copy,
overwriting any existing values
for the keywords.
Example:
-
env2 = env.Clone() env3 = env.Clone(CCFLAGS = '-g')
-
-
Additionally, a list of tools and a toolpath may be specified, as in
the Environment constructor:
-
def MyTool(env): env['FOO'] = 'bar' env4 = env.Clone(tools = ['msvc', MyTool])
The parse_flags keyword argument is also recognized:
-
# create an environment for compiling programs that use wxWidgets wx_env = env.Clone(parse_flags = '!wx-config --cflags --cxxflags')
-
- env.Copy([key=val, ...])
-
A now-deprecated synonym for
env.Clone().
- env.CVS(repository, module)
-
A factory function that
returns a Builder object
to be used to fetch source files
from the specified
CVS
repository.
The returned Builder
is intended to be passed to the
SourceCode
function.
The optional specified module will be added to the beginning of all repository path names; this can be used, in essence, to strip initial directory names from the repository path names, so that you only have to replicate part of the repository directory hierarchy in your local build directory.
This function is deprecated. For details, see the entry for the SourceCode function.
Examples:
-
# Will fetch foo/bar/src.c # from /usr/local/CVSROOT/foo/bar/src.c. env.SourceCode('.', env.CVS('/usr/local/CVSROOT')) # Will fetch bar/src.c # from /usr/local/CVSROOT/foo/bar/src.c. env.SourceCode('.', env.CVS('/usr/local/CVSROOT', 'foo')) # Will fetch src.c # from /usr/local/CVSROOT/foo/bar/src.c. env.SourceCode('.', env.CVS('/usr/local/CVSROOT', 'foo/bar'))
-
- Decider(function)
- env.Decider(function)
-
Specifies that all up-to-date decisions for
targets built through this construction environment
will be handled by the specified
function.
The
function
can be one of the following strings
that specify the type of decision function
to be performed:
-
- timestamp-newer
- Specifies that a target shall be considered out of date and rebuilt
if the dependency's timestamp is newer than the target file's timestamp.
This is the behavior of the classic Make utility,
and
make
can be used a synonym for
timestamp-newer.
- timestamp-match
- Specifies that a target shall be considered out of date and rebuilt
if the dependency's timestamp is different than the
timestamp recorded the last time the target was built.
This provides behavior very similar to the classic Make utility
(in particular, files are not opened up so that their
contents can be checksummed)
except that the target will also be rebuilt if a
dependency file has been restored to a version with an
earlier
timestamp, such as can happen when restoring files from backup archives.
- MD5
- Specifies that a target shall be considered out of date and rebuilt
if the dependency's content has changed sine the last time
the target was built,
as determined be performing an MD5 checksum
on the dependency's contents
and comparing it to the checksum recorded the
last time the target was built.
content
can be used as a synonym for
MD5.
- MD5-timestamp
- Specifies that a target shall be considered out of date and rebuilt if the dependency's content has changed sine the last time the target was built, except that dependencies with a timestamp that matches the last time the target was rebuilt will be assumed to be up-to-date and not rebuilt. This provides behavior very similar to the MD5 behavior of always checksumming file contents, with an optimization of not checking the contents of files whose timestamps haven't changed. The drawback is that SCons will not detect if a file's content has changed but its timestamp is the same, as might happen in an automated script that runs a build, updates a file, and runs the build again, all within a single second.
-
-
Examples:
-
# Use exact timestamp matches by default. Decider('timestamp-match') # Use MD5 content signatures for any targets built # with the attached construction environment. env.Decider('content')
-
-
In addition to the above already-available functions,
the
function
argument may be an actual Python function
that takes the following three arguments:
-
- dependency
-
The Node (file) which
should cause the
target
to be rebuilt
if it has "changed" since the last tme
target was built.
- target
-
The Node (file) being built.
In the normal case,
this is what should get rebuilt
if the
dependency
has "changed."
- prev_ni
- Stored information about the state of the dependency the last time the target was built. This can be consulted to match various file characteristics such as the timestamp, size, or content signature.
-
-
The
function
should return a
True
(non-zero)
value if the
dependency
has "changed" since the last time
the
target
was built
(indicating that the target
should
be rebuilt),
and
False
(zero)
otherwise
(indicating that the target should
not
be rebuilt).
Note that the decision can be made
using whatever criteria are appopriate.
Ignoring some or all of the function arguments
is perfectly normal.
Example:
-
def my_decider(dependency, target, prev_ni): return not os.path.exists(str(target)) env.Decider(my_decider)
-
- Default(targets)
- env.Default(targets)
-
This specifies a list of default targets,
which will be built by
scons
if no explicit targets are given on the command line.
Multiple calls to
Default()
are legal,
and add to the list of default targets.
Multiple targets should be specified as separate arguments to the Default() method, or as a list. Default() will also accept the Node returned by any of a construction environment's builder methods.
Examples:
-
Default('foo', 'bar', 'baz') env.Default(['a', 'b', 'c']) hello = env.Program('hello', 'hello.c') env.Default(hello)
-
-
An argument to
Default()
of
None
will clear all default targets.
Later calls to
Default()
will add to the (now empty) default-target list
like normal.
The current list of targets added using the Default() function or method is available in the DEFAULT_TARGETS list; see below.
- DefaultEnvironment([args])
-
Creates and returns a default construction environment object.
This construction environment is used internally by SCons
in order to execute many of the global functions in this list,
and to fetch source files transparently
from source code management systems.
- Depends(target, dependency)
- env.Depends(target, dependency)
-
Specifies an explicit dependency;
the
target
will be rebuilt
whenever the
dependency
has changed.
Both the specified
target
and
dependency
can be a string
(usually the path name of a file or directory)
or Node objects,
or a list of strings or Node objects
(such as returned by a Builder call).
This should only be necessary
for cases where the dependency
is not caught by a Scanner
for the file.
Example:
-
env.Depends('foo', 'other-input-file-for-foo') mylib = env.Library('mylib.c') installed_lib = env.Install('lib', mylib) bar = env.Program('bar.c') # Arrange for the library to be copied into the installation # directory before trying to build the "bar" program. # (Note that this is for example only. A "real" library # dependency would normally be configured through the $LIBS # and $LIBPATH variables, not using an env.Depends() call.) env.Depends(bar, installed_lib)
-
- env.Dictionary([vars])
-
Returns a dictionary object
containing copies of all of the
construction variables in the environment.
If there are any variable names specified,
only the specified construction
variables are returned in the dictionary.
Example:
-
dict = env.Dictionary() cc_dict = env.Dictionary('CC', 'CCFLAGS', 'CCCOM')
-
- Dir(name, [directory])
- env.Dir(name, [directory])
-
This returns a Directory Node,
an object that represents the specified directory
name.
name
can be a relative or absolute path.
directory
is an optional directory that will be used as the parent directory.
If no
directory
is specified, the current script's directory is used as the parent.
If name is a list, SCons returns a list of Dir nodes. Construction variables are expanded in name.
Directory Nodes can be used anywhere you would supply a string as a directory name to a Builder method or function. Directory Nodes have attributes and methods that are useful in many situations; see "File and Directory Nodes," below.
- env.Dump([key])
-
Returns a pretty printable representation of the environment.
key,
if not
None,
should be a string containing the name of the variable of interest.
This SConstruct:
-
env=Environment() print env.Dump('CCCOM')
-
-
will print:
-
'$CC -c -o $TARGET $CCFLAGS $CPPFLAGS $_CPPDEFFLAGS $_CPPINCFLAGS $SOURCES'
-
env=Environment() print env.Dump()
-
-
will print:
-
{ 'AR': 'ar', 'ARCOM': '$AR $ARFLAGS $TARGET $SOURCESRANLIB $RANLIBFLAGS $TARGET', 'ARFLAGS': ['r'], 'AS': 'as', 'ASCOM': '$AS $ASFLAGS -o $TARGET $SOURCES', 'ASFLAGS': [], ...
-
- EnsurePythonVersion(major, minor)
- env.EnsurePythonVersion(major, minor)
-
Ensure that the Python version is at least
major.minor.
This function will
print out an error message and exit SCons with a non-zero exit code if the
actual Python version is not late enough.
Example:
-
EnsurePythonVersion(2,2)
-
- EnsureSConsVersion(major, minor, [revision])
- env.EnsureSConsVersion(major, minor, [revision])
-
Ensure that the SCons version is at least
major.minor,
or
major.minor.revision.
if
revision
is specified.
This function will
print out an error message and exit SCons with a non-zero exit code if the
actual SCons version is not late enough.
Examples:
-
EnsureSConsVersion(0,14) EnsureSConsVersion(0,96,90)
-
- Environment([key=value, ...])
- env.Environment([key=value, ...])
-
Return a new construction environment
initialized with the specified
key=value
pairs.
- Execute(action, [strfunction, varlist])
- env.Execute(action, [strfunction, varlist])
-
Executes an Action object.
The specified
action
may be an Action object
(see the section "Action Objects,"
below, for a complete explanation of the arguments and behavior),
or it may be a command-line string,
list of commands,
or executable Python function,
each of which will be converted
into an Action object
and then executed.
The exit value of the command
or return value of the Python function
will be returned.
Note that scons will print an error message if the executed action fails--that is, exits with or returns a non-zero value. scons will not , however, automatically terminate the build if the specified action fails. If you want the build to stop in response to a failed Execute() call, you must explicitly check for a non-zero return value:
-
Execute(Copy('file.out', 'file.in')) if Execute("mkdir sub/dir/ectory"): # The mkdir failed, don't try to build. Exit(1)
-
- Exit([value])
- env.Exit([value])
-
This tells
scons
to exit immediately
with the specified
value.
A default exit value of
0
(zero)
is used if no value is specified.
- Export(vars)
- env.Export(vars)
-
This tells
scons
to export a list of variables from the current
SConscript file to all other SConscript files.
The exported variables are kept in a global collection,
so subsequent calls to
Export()
will over-write previous exports that have the same name.
Multiple variable names can be passed to
Export()
as separate arguments or as a list.
Keyword arguments can be used to provide names and their values.
A dictionary can be used to map variables to a different name when exported.
Both local variables and global variables can be exported.
Examples:
-
env = Environment() # Make env available for all SConscript files to Import(). Export("env") package = 'my_name' # Make env and package available for all SConscript files:. Export("env", "package") # Make env and package available for all SConscript files: Export(["env", "package"]) # Make env available using the name debug: Export(debug = env) # Make env available using the name debug: Export({"debug":env})
-
-
Note that the
SConscript()
function supports an
exports
argument that makes it easier to to export a variable or
set of variables to a single SConscript file.
See the description of the
SConscript()
function, below.
- File(name, [directory])
- env.File(name, [directory])
-
This returns a
File Node,
an object that represents the specified file
name.
name
can be a relative or absolute path.
directory
is an optional directory that will be used as the parent directory.
If name is a list, SCons returns a list of File nodes. Construction variables are expanded in name.
File Nodes can be used anywhere you would supply a string as a file name to a Builder method or function. File Nodes have attributes and methods that are useful in many situations; see "File and Directory Nodes," below.
- FindFile(file, dirs)
- env.FindFile(file, dirs)
-
Search for
file
in the path specified by
dirs.
dirs
may be a list of directory names or a single directory name.
In addition to searching for files that exist in the filesystem,
this function also searches for derived files
that have not yet been built.
Example:
-
foo = env.FindFile('foo', ['dir1', 'dir2'])
-
- FindInstalledFiles()
- env.FindInstalledFiles()
-
Returns the list of targets set up by the
Install()
or
InstallAs()
builders.
This function serves as a convenient method to select the contents of a binary package.
Example:
-
Install( '/bin', [ 'executable_a', 'executable_b' ] ) # will return the file node list # [ '/bin/executable_a', '/bin/executable_b' ] FindInstalledFiles() Install( '/lib', [ 'some_library' ] ) # will return the file node list # [ '/bin/executable_a', '/bin/executable_b', '/lib/some_library' ] FindInstalledFiles()
-
- FindSourceFiles(node='.')
- env.FindSourceFiles(node='.')
-
Returns the list of nodes which serve as the source of the built files. It does so by inspecting the dependency tree starting at the optional argument node which defaults to the '"."'-node. It will then return all leaves of node. These are all children which have no further children.
This function is a convenient method to select the contents of a Source Package.
Example:
-
Program( 'src/main_a.c' ) Program( 'src/main_b.c' ) Program( 'main_c.c' ) # returns ['main_c.c', 'src/main_a.c', 'SConstruct', 'src/main_b.c'] FindSourceFiles() # returns ['src/main_b.c', 'src/main_a.c' ] FindSourceFiles( 'src' )
-
-
As you can see build support files (SConstruct in the above example)
will also be returned by this function.
- FindPathDirs(variable)
-
Returns a function
(actually a callable Python object)
intended to be used as the
path_function
of a Scanner object.
The returned object will look up the specified
variable
in a construction environment
and treat the construction variable's value as a list of
directory paths that should be searched
(like
CPPPATH,
LIBPATH,
etc.).
Note that use of FindPathDirs() is generally preferable to writing your own path_function for the following reasons: 1) The returned list will contain all appropriate directories found in source trees (when VariantDir() is used) or in code repositories (when Repository() or the -Y option are used). 2) scons will identify expansions of variable that evaluate to the same list of directories as, in fact, the same list, and avoid re-scanning the directories for files, when possible.
Example:
-
def my_scan(node, env, path, arg): # Code to scan file contents goes here... return include_files scanner = Scanner(name = 'myscanner', function = my_scan, path_function = FindPathDirs('MYPATH'))
-
- Flatten(sequence)
- env.Flatten(sequence)
-
Takes a sequence (that is, a Python list or tuple)
that may contain nested sequences
and returns a flattened list containing
all of the individual elements in any sequence.
This can be helpful for collecting
the lists returned by calls to Builders;
other Builders will automatically
flatten lists specified as input,
but direct Python manipulation of
these lists does not.
Examples:
-
foo = Object('foo.c') bar = Object('bar.c') # Because `foo' and `bar' are lists returned by the Object() Builder, # `objects' will be a list containing nested lists: objects = ['f1.o', foo, 'f2.o', bar, 'f3.o'] # Passing such a list to another Builder is all right because # the Builder will flatten the list automatically: Program(source = objects) # If you need to manipulate the list directly using Python, you need to # call Flatten() yourself, or otherwise handle nested lists: for object in Flatten(objects): print str(object)
-
- GetBuildFailures()
-
Returns a list of exceptions for the
actions that failed while
attempting to build targets.
Each element in the returned list is a
BuildError
object
with the following attributes
that record various aspects
of the build failure:
.node The node that was being built when the build failure occurred.
.status The numeric exit status returned by the command or Python function that failed when trying to build the specified Node.
.errstr The SCons error string describing the build failure. (This is often a generic message like "Error 2" to indicate that an executed command exited with a status of 2.)
.filename The name of the file or directory that actually caused the failure. This may be different from the .node attribute. For example, if an attempt to build a target named sub/dir/target fails because the sub/dir directory could not be created, then the .node attribute will be sub/dir/target but the .filename attribute will be sub/dir.
.executor The SCons Executor object for the target Node being built. This can be used to retrieve the construction environment used for the failed action.
.action The actual SCons Action object that failed. This will be one specific action out of the possible list of actions that would have been executed to build the target.
.command The actual expanded command that was executed and failed, after expansion of $TARGET, $SOURCE, and other construction variables.
Note that the GetBuildFailures() function will always return an empty list until any build failure has occurred, which means that GetBuildFailures() will always return an empty list while the SConscript files are being read. Its primary intended use is for functions that will be executed before SCons exits by passing them to the standard Python atexit.register() function. Example:
-
import atexit def print_build_failures(): from SCons.Script import GetBuildFailures for bf in GetBuildFailures(): print "%s failed: %s" % (bf.node, bf.errstr) atexit.register(print_build_failures)
-
- GetBuildPath(file, [...])
- env.GetBuildPath(file, [...])
-
Returns the
scons
path name (or names) for the specified
file
(or files).
The specified
file
or files
may be
scons
Nodes or strings representing path names.
- GetLaunchDir()
- env.GetLaunchDir()
-
Returns the absolute path name of the directory from which
scons
was initially invoked.
This can be useful when using the
-u,
-U
or
-D
options, which internally
change to the directory in which the
SConstruct
file is found.
- GetOption(name)
- env.GetOption(name)
-
This function provides a way to query the value of
SCons options set on scons command line
(or set using the
SetOption()
function).
The options supported are:
-
- cache_debug
- which corresponds to --cache-debug;
- cache_disable
- which corresponds to --cache-disable;
- cache_force
- which corresponds to --cache-force;
- cache_show
- which corresponds to --cache-show;
- clean
- which corresponds to -c, --clean and --remove;
- config
- which corresponds to --config;
- directory
- which corresponds to -C and --directory;
- diskcheck
- which corresponds to --diskcheck
- duplicate
- which corresponds to --duplicate;
- file
- which corresponds to -f, --file, --makefile and --sconstruct;
- help
- which corresponds to -h and --help;
- ignore_errors
- which corresponds to --ignore-errors;
- implicit_cache
- which corresponds to --implicit-cache;
- implicit_deps_changed
- which corresponds to --implicit-deps-changed;
- implicit_deps_unchanged
- which corresponds to --implicit-deps-unchanged;
- interactive
- which corresponds to --interact and --interactive;
- keep_going
- which corresponds to -k and --keep-going;
- max_drift
- which corresponds to --max-drift;
- no_exec
- which corresponds to -n, --no-exec, --just-print, --dry-run and --recon;
- no_site_dir
- which corresponds to --no-site-dir;
- num_jobs
- which corresponds to -j and --jobs;
- profile_file
- which corresponds to --profile;
- question
- which corresponds to -q and --question;
- random
- which corresponds to --random;
- repository
- which corresponds to -Y, --repository and --srcdir;
- silent
- which corresponds to -s, --silent and --quiet;
- site_dir
- which corresponds to --site-dir;
- stack_size
- which corresponds to --stack-size;
- taskmastertrace_file
- which corresponds to --taskmastertrace; and
- warn
- which corresponds to --warn and --warning.
-
-
See the documentation for the
corresponding command line object for information about each specific
option.
- Glob(pattern, [ondisk, source, strings])
- env.Glob(pattern, [ondisk, source, strings])
-
Returns Nodes (or strings) that match the specified
pattern,
relative to the directory of the current
SConscript
file.
The
env.Glob()
form performs string substition on
pattern
and returns whatever matches
the resulting expanded pattern.
The specified pattern uses Unix shell style metacharacters for matching:
-
* matches everything ? matches any single character [seq] matches any character in seq [!seq] matches any char not in seq
-
-
If the first character of a filename is a dot,
it must be matched explicitly.
Character matches do
not
span directory separators.
The Glob() knows about repositories (see the Repository() function) and source directories (see the VariantDir() function) and returns a Node (or string, if so configured) in the local (SConscript) directory if matching Node is found anywhere in a corresponding repository or source directory.
The ondisk argument may be set to False (or any other non-true value) to disable the search for matches on disk, thereby only returning matches among already-configured File or Dir Nodes. The default behavior is to return corresponding Nodes for any on-disk matches found.
The source argument may be set to True (or any equivalent value) to specify that, when the local directory is a VariantDir(), the returned Nodes should be from the corresponding source directory, not the local directory.
The strings argument may be set to True (or any equivalent value) to have the Glob() function return strings, not Nodes, that represent the matched files or directories. The returned strings will be relative to the local (SConscript) directory. (Note that This may make it easier to perform arbitrary manipulation of file names, but if the returned strings are passed to a different SConscript file, any Node translation will be relative to the other SConscript directory, not the original SConscript directory.)
Examples:
-
Program('foo', Glob('*.c')) Zip('/tmp/everything', Glob('.??*') + Glob('*'))
-
- Help(text)
- env.Help(text)
-
This specifies help text to be printed if the
-h
argument is given to
scons.
If
Help
is called multiple times, the text is appended together in the order
that
Help
is called.
- Ignore(target, dependency)
- env.Ignore(target, dependency)
-
The specified dependency file(s)
will be ignored when deciding if
the target file(s) need to be rebuilt.
You can also use Ignore() to remove a target from the default build. In order to do this you must specify the directory the target will be built in as the target, and the file you want to skip building as the dependency.
Note that this will only remove the dependencies listed from the files built by default. It will still be built if that dependency is needed by another object being built. See the third and forth examples below.
Examples:
-
env.Ignore('foo', 'foo.c') env.Ignore('bar', ['bar1.h', 'bar2.h']) env.Ignore('.','foobar.obj') env.Ignore('bar','bar/foobar.obj')
-
- Import(vars)
- env.Import(vars)
-
This tells
scons
to import a list of variables into the current SConscript file. This
will import variables that were exported with
Export()
or in the
exports
argument to
SConscript().
Variables exported by
SConscript()
have precedence.
Multiple variable names can be passed to
Import()
as separate arguments or as a list. The variable "*" can be used
to import all variables.
Examples:
-
Import("env") Import("env", "variable") Import(["env", "variable"]) Import("*")
-
- Literal(string)
- env.Literal(string)
-
The specified
string
will be preserved as-is
and not have construction variables expanded.
- Local(targets)
- env.Local(targets)
-
The specified
targets
will have copies made in the local tree,
even if an already up-to-date copy
exists in a repository.
Returns a list of the target Node or Nodes.
- env.MergeFlags(arg, [unique])
-
Merges the specified
arg
values to the construction environment's construction variables.
If the
arg
argument is not a dictionary,
it is converted to one by calling
env.ParseFlags()
on the argument
before the values are merged.
Note that
arg
must be a single value,
so multiple strings must
be passed in as a list,
not as separate arguments to
env.MergeFlags().
By default, duplicate values are eliminated; you can, however, specify unique=0 to allow duplicate values to be added. When eliminating duplicate values, any construction variables that end with the string PATH keep the left-most unique value. All other construction variables keep the right-most unique value.
Examples:
-
# Add an optimization flag to $CCFLAGS. env.MergeFlags('-O3') # Combine the flags returned from running pkg-config with an optimization # flag and merge the result into the construction variables. env.MergeFlags(['!pkg-config gtk+-2.0 --cflags', '-O3']) # Combine an optimization flag with the flags returned from running pkg-config # twice and merge the result into the construction variables. env.MergeFlags(['-O3', '!pkg-config gtk+-2.0 --cflags --libs', '!pkg-config libpng12 --cflags --libs'])
-
- NoCache(target, ...)
- env.NoCache(target, ...)
-
Specifies a list of files which should
not
be cached whenever the
CacheDir()
method has been activated.
The specified targets may be a list
or an individual target.
Multiple files should be specified either as separate arguments to the NoCache() method, or as a list. NoCache() will also accept the return value of any of the construction environment Builder methods.
Calling NoCache() on directories and other non-File Node types has no effect because only File Nodes are cached.
Examples:
-
NoCache('foo.elf') NoCache(env.Program('hello', 'hello.c'))
-
- NoClean(target, ...)
- env.NoClean(target, ...)
-
Specifies a list of files or directories which should
not
be removed whenever the targets (or their dependencies)
are specified with the
-c
command line option.
The specified targets may be a list
or an individual target.
Multiple calls to
NoClean()
are legal,
and prevent each specified target
from being removed by calls to the
-c
option.
Multiple files or directories should be specified either as separate arguments to the NoClean() method, or as a list. NoClean() will also accept the return value of any of the construction environment Builder methods.
Calling NoClean() for a target overrides calling Clean() for the same target, and any targets passed to both functions will not be removed by the -c option.
Examples:
-
NoClean('foo.elf') NoClean(env.Program('hello', 'hello.c'))
-
- env.ParseConfig(command, [function, unique])
-
Calls the specified
function
to modify the environment as specified by the output of
command .
The default
function
is
env.MergeFlags(),
which expects the output of a typical
*-config command
(for example,
gtk-config)
and adds the options
to the appropriate construction variables.
By default,
duplicate values are not
added to any construction variables;
you can specify
unique=0
to allow duplicate
values to be added.
Interpreted options and the construction variables they affect are as specified for the env.ParseFlags() method (which this method calls). See that method's description, below, for a table of options and construction variables.
- ParseDepends(filename, [must_exist, only_one])
- env.ParseDepends(filename, [must_exist, only_one])
-
Parses the contents of the specified
filename
as a list of dependencies in the style of
Make
or
mkdep,
and explicitly establishes all of the listed dependencies.
By default, it is not an error if the specified filename does not exist. The optional must_exist argument may be set to a non-zero value to have scons throw an exception and generate an error if the file does not exist, or is otherwise inaccessible.
The optional only_one argument may be set to a non-zero value to have scons thrown an exception and generate an error if the file contains dependency information for more than one target. This can provide a small sanity check for files intended to be generated by, for example, the gcc -M flag, which should typically only write dependency information for one output file into a corresponding .d file.
The filename and all of the files listed therein will be interpreted relative to the directory of the SConscript file which calls the ParseDepends function.
- env.ParseFlags(flags, ...)
-
Parses one or more strings containing
typical command-line flags for GCC tool chains
and returns a dictionary with the flag values
separated into the appropriate SCons construction variables.
This is intended as a companion to the
env.MergeFlags()
method, but allows for the values in the returned dictionary
to be modified, if necessary,
before merging them into the construction environment.
(Note that
env.MergeFlags()
will call this method if its argument is not a dictionary,
so it is usually not necessary to call
env.ParseFlags()
directly unless you want to manipulate the values.)
If the first character in any string is an exclamation mark (!), the rest of the string is executed as a command, and the output from the command is parsed as GCC tool chain command-line flags and added to the resulting dictionary.
Flag values are translated accordig to the prefix found, and added to the following construction variables:
-
-arch CCFLAGS, LINKFLAGS -D CPPDEFINES -framework FRAMEWORKS -frameworkdir= FRAMEWORKPATH -include CCFLAGS -isysroot CCFLAGS, LINKFLAGS -I CPPPATH -l LIBS -L LIBPATH -mno-cygwin CCFLAGS, LINKFLAGS -mwindows LINKFLAGS -pthread CCFLAGS, LINKFLAGS -std= CFLAGS -Wa, ASFLAGS, CCFLAGS -Wl,-rpath= RPATH -Wl,-R, RPATH -Wl,-R RPATH -Wl, LINKFLAGS -Wp, CPPFLAGS - CCFLAGS + CCFLAGS, LINKFLAGS
-
-
Any other strings not associated with options
are assumed to be the names of libraries
and added to the
LIBS
construction variable.
Examples (all of which produce the same result):
-
dict = env.ParseFlags('-O2 -Dfoo -Dbar=1') dict = env.ParseFlags('-O2', '-Dfoo', '-Dbar=1') dict = env.ParseFlags(['-O2', '-Dfoo -Dbar=1']) dict = env.ParseFlags('-O2', '!echo -Dfoo -Dbar=1')
-
- env.Perforce()
-
A factory function that
returns a Builder object
to be used to fetch source files
from the Perforce source code management system.
The returned Builder
is intended to be passed to the
SourceCode
function.
This function is deprecated. For details, see the entry for the SourceCode function.
Example:
-
env.SourceCode('.', env.Perforce())
-
-
Perforce uses a number of external
environment variables for its operation.
Consequently, this function adds the
following variables from the user's external environment
to the construction environment's
ENV dictionary:
P4CHARSET,
P4CLIENT,
P4LANGUAGE,
P4PASSWD,
P4PORT,
P4USER,
SystemRoot,
USER,
and
USERNAME.
- Platform(string)
-
Returns a callable object
that can be used to initialize
a construction environment using the
platform keyword of the Environment() method.
Example:
-
env = Environment(platform = Platform('win32'))
-
- env.Platform(string)
-
Applies the callable object for the specified platform
string
to the environment through which the method was called.
-
env.Platform('posix')
-
-
Note that the
win32
platform adds the
SystemDrive
and
SystemRoot
variables from the user's external environment
to the construction environment's
ENV
dictionary.
This is so that any executed commands
that use sockets to connect with other systems
(such as fetching source files from
external CVS repository specifications like
:pserver:anonymous@cvs.sourceforge.net:/cvsroot/scons)
will work on Windows systems.
- Progress(callable, [interval])
- Progress(string, [interval, file, overwrite])
- Progress(list_of_strings, [interval, file, overwrite])
-
Allows SCons to show progress made during the build
by displaying a string or calling a function while
evaluating Nodes (e.g. files).
If the first specified argument is a Python callable (a function or an object that has a __call__() method), the function will be called once every interval times a Node is evaluated. The callable will be passed the evaluated Node as its only argument. (For future compatibility, it's a good idea to also add *args and **kw as arguments to your function or method. This will prevent the code from breaking if SCons ever changes the interface to call the function with additional arguments in the future.)
An example of a simple custom progress function that prints a string containing the Node name every 10 Nodes:
-
def my_progress_function(node, *args, **kw): print 'Evaluating node %s!' % node Progress(my_progress_function, interval=10)
-
-
A more complicated example of a custom progress display object
that prints a string containing a count
every 100 evaluated Nodes.
Note the use of
\\r
(a carriage return)
at the end so that the string
will overwrite itself on a display:
-
import sys class ProgressCounter(object): count = 0 def __call__(self, node, *args, **kw): self.count += 100 sys.stderr.write('Evaluated %s nodes\r' % self.count) Progress(ProgressCounter(), interval=100)
-
-
If the first argument
Progress()
is a string,
the string will be displayed
every
interval
evaluated Nodes.
The default is to print the string on standard output;
an alternate output stream
may be specified with the
file=
argument.
The following will print a series of dots
on the error output,
one dot for every 100 evaluated Nodes:
-
import sys Progress('.', interval=100, file=sys.stderr)
-
-
If the string contains the verbatim substring
$TARGET,
it will be replaced with the Node.
Note that, for performance reasons, this is
not
a regular SCons variable substition,
so you can not use other variables
or use curly braces.
The following example will print the name of
every evaluated Node,
using a
\\r
(carriage return) to cause each line to overwritten by the next line,
and the
overwrite=
keyword argument to make sure the previously-printed
file name is overwritten with blank spaces:
-
import sys Progress('$TARGET\r', overwrite=True)
-
-
If the first argument to
Progress()
is a list of strings,
then each string in the list will be displayed
in rotating fashion every
interval
evaluated Nodes.
This can be used to implement a "spinner"
on the user's screen as follows:
-
Progress(['-\r', '\\\r', '|\r', '/\r'], interval=5)
-
- Precious(target, ...)
- env.Precious(target, ...)
-
Marks each given
target
as precious so it is not deleted before it is rebuilt. Normally
scons
deletes a target before building it.
Multiple targets can be passed in to a single call to
Precious().
- env.Prepend(key=val, [...])
-
Appends the specified keyword arguments
to the beginning of construction variables in the environment.
If the Environment does not have
the specified construction variable,
it is simply added to the environment.
If the values of the construction variable
and the keyword argument are the same type,
then the two values will be simply added together.
Otherwise, the construction variable
and the value of the keyword argument
are both coerced to lists,
and the lists are added together.
(See also the Append method, above.)
Example:
-
env.Prepend(CCFLAGS = '-g ', FOO = ['foo.yyy'])
-
- env.PrependENVPath(name, newpath, [envname, sep, delete_existing])
-
This appends new path elements to the given path in the
specified external environment
(ENV
by default).
This will only add
any particular path once (leaving the first one it encounters and
ignoring the rest, to preserve path order),
and to help assure this,
will normalize all paths (using
os.path.normpath
and
os.path.normcase).
This can also handle the
case where the given old path variable is a list instead of a
string, in which case a list will be returned instead of a string.
If delete_existing is 0, then adding a path that already exists will not move it to the beginning; it will stay where it is in the list.
Example:
-
print 'before:',env['ENV']['INCLUDE'] include_path = '/foo/bar:/foo' env.PrependENVPath('INCLUDE', include_path) print 'after:',env['ENV']['INCLUDE']
The above exmaple will print:
-
before: /biz:/foo after: /foo/bar:/foo:/biz
-
- env.PrependUnique(key=val, delete_existing=0, [...])
-
Appends the specified keyword arguments
to the beginning of construction variables in the environment.
If the Environment does not have
the specified construction variable,
it is simply added to the environment.
If the construction variable being appended to is a list,
then any value(s) that already exist in the
construction variable will
not
be added again to the list.
However, if delete_existing is 1,
existing matching values are removed first, so
existing values in the arg list move to the front of the list.
Example:
-
env.PrependUnique(CCFLAGS = '-g', FOO = ['foo.yyy'])
-
- env.RCS()
-
A factory function that
returns a Builder object
to be used to fetch source files
from RCS.
The returned Builder
is intended to be passed to the
SourceCode
function:
This function is deprecated. For details, see the entry for the SourceCode function.
Examples:
-
env.SourceCode('.', env.RCS())
-
-
Note that
scons
will fetch source files
from RCS subdirectories automatically,
so configuring RCS
as demonstrated in the above example
should only be necessary if
you are fetching from
RCS,v
files in the same
directory as the source files,
or if you need to explicitly specify RCS
for a specific subdirectory.
- env.Replace(key=val, [...])
-
Replaces construction variables in the Environment
with the specified keyword arguments.
Example:
-
env.Replace(CCFLAGS = '-g', FOO = 'foo.xxx')
-
- Repository(directory)
- env.Repository(directory)
-
Specifies that
directory
is a repository to be searched for files.
Multiple calls to
Repository()
are legal,
and each one adds to the list of
repositories that will be searched.
To scons, a repository is a copy of the source tree, from the top-level directory on down, which may contain both source files and derived files that can be used to build targets in the local source tree. The canonical example would be an official source tree maintained by an integrator. If the repository contains derived files, then the derived files should have been built using scons, so that the repository contains the necessary signature information to allow scons to figure out when it is appropriate to use the repository copy of a derived file, instead of building one locally.
Note that if an up-to-date derived file already exists in a repository, scons will not make a copy in the local directory tree. In order to guarantee that a local copy will be made, use the Local() method.
- Requires(target, prerequisite)
- env.Requires(target, prerequisite)
-
Specifies an order-only relationship
between the specified target file(s)
and the specified prerequisite file(s).
The prerequisite file(s)
will be (re)built, if necessary,
before
the target file(s),
but the target file(s) do not actually
depend on the prerequisites
and will not be rebuilt simply because
the prerequisite file(s) change.
Example:
-
env.Requires('foo', 'file-that-must-be-built-before-foo')
-
- Return([vars... , stop=])
-
By default,
this stops processing the current SConscript
file and returns to the calling SConscript file
the values of the variables named in the
vars
string arguments.
Multiple strings contaning variable names may be passed to
Return().
Any strings that contain white space
The optional stop= keyword argument may be set to a false value to continue processing the rest of the SConscript file after the Return() call. This was the default behavior prior to SCons 0.98. However, the values returned are still the values of the variables in the named vars at the point Return() is called.
Examples:
-
# Returns without returning a value. Return() # Returns the value of the 'foo' Python variable. Return("foo") # Returns the values of the Python variables 'foo' and 'bar'. Return("foo", "bar") # Returns the values of Python variables 'val1' and 'val2'. Return('val1 val2')
-
- Scanner(function, [argument, keys, path_function, node_class, node_factory, scan_check, recursive])
- env.Scanner(function, [argument, keys, path_function, node_class, node_factory, scan_check, recursive])
-
Creates a Scanner object for
the specified
function.
See the section "Scanner Objects,"
below, for a complete explanation of the arguments and behavior.
- env.SCCS()
-
A factory function that
returns a Builder object
to be used to fetch source files
from SCCS.
The returned Builder
is intended to be passed to the
SourceCode
function.
This function is deprecated. For details, see the entry for the SourceCode function.
Example:
-
env.SourceCode('.', env.SCCS())
-
-
Note that
scons
will fetch source files
from SCCS subdirectories automatically,
so configuring SCCS
as demonstrated in the above example
should only be necessary if
you are fetching from
s.SCCS
files in the same
directory as the source files,
or if you need to explicitly specify SCCS
for a specific subdirectory.
- SConscript(scripts, [exports, variant_dir, duplicate])
- env.SConscript(scripts, [exports, variant_dir, duplicate])
- SConscript(dirs=subdirs, [name=script, exports, variant_dir, duplicate])
- env.SConscript(dirs=subdirs, [name=script, exports, variant_dir, duplicate])
-
This tells
scons
to execute
one or more subsidiary SConscript (configuration) files.
Any variables returned by a called script using
Return()
will be returned by the call to
SConscript().
There are two ways to call the
SConscript()
function.
The first way you can call SConscript() is to explicitly specify one or more scripts as the first argument. A single script may be specified as a string; multiple scripts must be specified as a list (either explicitly or as created by a function like Split()). Examples:
-
SConscript('SConscript') # run SConscript in the current directory SConscript('src/SConscript') # run SConscript in the src directory SConscript(['src/SConscript', 'doc/SConscript']) config = SConscript('MyConfig.py')
The second way you can call SConscript() is to specify a list of (sub)directory names as a dirs=subdirs keyword argument. In this case, scons will, by default, execute a subsidiary configuration file named SConscript in each of the specified directories. You may specify a name other than SConscript by supplying an optional name=script keyword argument. The first three examples below have the same effect as the first three examples above:
-
SConscript(dirs='.') # run SConscript in the current directory SConscript(dirs='src') # run SConscript in the src directory SConscript(dirs=['src', 'doc']) SConscript(dirs=['sub1', 'sub2'], name='MySConscript')
The optional exports argument provides a list of variable names or a dictionary of named values to export to the script(s). These variables are locally exported only to the specified script(s), and do not affect the global pool of variables used by the Export() function. The subsidiary script(s) must use the Import() function to import the variables. Examples:
-
foo = SConscript('sub/SConscript', exports='env') SConscript('dir/SConscript', exports=['env', 'variable']) SConscript(dirs='subdir', exports='env variable') SConscript(dirs=['one', 'two', 'three'], exports='shared_info')
If the optional variant_dir argument is present, it causes an effect equivalent to the VariantDir() method described below. (If variant_dir is not present, the duplicate argument is ignored.) The variant_dir argument is interpreted relative to the directory of the calling SConscript file. See the description of the VariantDir() function below for additional details and restrictions.
If variant_dir is present, the source directory is the directory in which the SConscript file resides and the SConscript file is evaluated as if it were in the variant_dir directory:
-
SConscript('src/SConscript', variant_dir = 'build')
-
VariantDir('build', 'src') SConscript('build/SConscript')
-
SConscript('SConscript', variant_dir = 'build')
-
VariantDir('build', '.') SConscript('build/SConscript')
Here are some composite examples:
-
# collect the configuration information and use it to build src and doc shared_info = SConscript('MyConfig.py') SConscript('src/SConscript', exports='shared_info') SConscript('doc/SConscript', exports='shared_info')
-
# build debugging and production versions. SConscript # can use Dir('.').path to determine variant. SConscript('SConscript', variant_dir='debug', duplicate=0) SConscript('SConscript', variant_dir='prod', duplicate=0)
-
# build debugging and production versions. SConscript # is passed flags to use. opts = { 'CPPDEFINES' : ['DEBUG'], 'CCFLAGS' : '-pgdb' } SConscript('SConscript', variant_dir='debug', duplicate=0, exports=opts) opts = { 'CPPDEFINES' : ['NODEBUG'], 'CCFLAGS' : '-O' } SConscript('SConscript', variant_dir='prod', duplicate=0, exports=opts)
-
# build common documentation and compile for different architectures SConscript('doc/SConscript', variant_dir='build/doc', duplicate=0) SConscript('src/SConscript', variant_dir='build/x86', duplicate=0) SConscript('src/SConscript', variant_dir='build/ppc', duplicate=0)
-
- SConscriptChdir(value)
- env.SConscriptChdir(value)
-
By default,
scons
changes its working directory
to the directory in which each
subsidiary SConscript file lives.
This behavior may be disabled
by specifying either:
-
SConscriptChdir(0) env.SConscriptChdir(0)
-
-
in which case
scons
will stay in the top-level directory
while reading all SConscript files.
(This may be necessary when building from repositories,
when all the directories in which SConscript files may be found
don't necessarily exist locally.)
You may enable and disable
this ability by calling
SConscriptChdir()
multiple times.
Example:
-
env = Environment() SConscriptChdir(0) SConscript('foo/SConscript') # will not chdir to foo env.SConscriptChdir(1) SConscript('bar/SConscript') # will chdir to bar
-
- SConsignFile([file,dbm_module])
- env.SConsignFile([file,dbm_module])
-
This tells
scons
to store all file signatures
in the specified database
file.
If the
file
name is omitted,
.sconsign
is used by default.
(The actual file name(s) stored on disk
may have an appropriated suffix appended
by the
dbm_module.)
If
file
is not an absolute path name,
the file is placed in the same directory as the top-level
SConstruct
file.
If file is None, then scons will store file signatures in a separate .sconsign file in each directory, not in one global database file. (This was the default behavior prior to SCons 0.96.91 and 0.97.)
The optional dbm_module argument can be used to specify which Python database module The default is to use a custom SCons.dblite module that uses pickled Python data structures, and which works on all Python versions.
Examples:
-
# Explicitly stores signatures in ".sconsign.dblite" # in the top-level SConstruct directory (the # default behavior). SConsignFile() # Stores signatures in the file "etc/scons-signatures" # relative to the top-level SConstruct directory. SConsignFile("etc/scons-signatures") # Stores signatures in the specified absolute file name. SConsignFile("/home/me/SCons/signatures") # Stores signatures in a separate .sconsign file # in each directory. SConsignFile(None)
-
- env.SetDefault(key=val, [...])
-
Sets construction variables to default values specified with the keyword
arguments if (and only if) the variables are not already set.
The following statements are equivalent:
-
env.SetDefault(FOO = 'foo') if 'FOO' not in env: env['FOO'] = 'foo'
-
- SetOption(name, value)
- env.SetOption(name, value)
-
This function provides a way to set a select subset of the scons command
line options from a SConscript file. The options supported are:
-
- clean
- which corresponds to -c, --clean and --remove;
- duplicate
- which corresponds to --duplicate;
- help
- which corresponds to -h and --help;
- implicit_cache
- which corresponds to --implicit-cache;
- max_drift
- which corresponds to --max-drift;
- no_exec
- which corresponds to -n, --no-exec, --just-print, --dry-run and --recon;
- num_jobs
- which corresponds to -j and --jobs;
- random
- which corresponds to --random; and
- stack_size
- which corresponds to --stack-size.
-
-
See the documentation for the
corresponding command line object for information about each specific
option.
Example:
-
SetOption('max_drift', 1)
-
- SideEffect(side_effect, target)
- env.SideEffect(side_effect, target)
-
Declares
side_effect
as a side effect of building
target.
Both
side_effect
and
target
can be a list, a file name, or a node.
A side effect is a target file that is created or updated
as a side effect of building other targets.
For example, a Windows PDB
file is created as a side effect of building the .obj
files for a static library,
and various log files are created updated
as side effects of various TeX commands.
If a target is a side effect of multiple build commands,
scons
will ensure that only one set of commands
is executed at a time.
Consequently, you only need to use this method
for side-effect targets that are built as a result of
multiple build commands.
Because multiple build commands may update the same side effect file, by default the side_effect target is not automatically removed when the target is removed by the -c option. (Note, however, that the side_effect might be removed as part of cleaning the directory in which it lives.) If you want to make sure the side_effect is cleaned whenever a specific target is cleaned, you must specify this explicitly with the Clean() or env.Clean() function.
- SourceCode(entries, builder)
- env.SourceCode(entries, builder)
-
This function and its associate factory functions are deprecated.
There is no replacement.
The intended use was to keep a local tree in sync with an archive,
but in actuality the function only causes the archive
to be fetched on the first run.
Synchronizing with the archive is best done external to SCons.
Arrange for non-existent source files to be fetched from a source code management system using the specified builder. The specified entries may be a Node, string or list of both, and may represent either individual source files or directories in which source files can be found.
For any non-existent source files, scons will search up the directory tree and use the first SourceCode builder it finds. The specified builder may be None, in which case scons will not use a builder to fetch source files for the specified entries, even if a SourceCode builder has been specified for a directory higher up the tree.
scons will, by default, fetch files from SCCS or RCS subdirectories without explicit configuration. This takes some extra processing time to search for the necessary source code management files on disk. You can avoid these extra searches and speed up your build a little by disabling these searches as follows:
-
env.SourceCode('.', None)
-
-
Note that if the specified
builder
is one you create by hand,
it must have an associated
construction environment to use
when fetching a source file.
scons provides a set of canned factory functions that return appropriate Builders for various popular source code management systems. Canonical examples of invocation include:
-
env.SourceCode('.', env.BitKeeper('/usr/local/BKsources')) env.SourceCode('src', env.CVS('/usr/local/CVSROOT')) env.SourceCode('/', env.RCS()) env.SourceCode(['f1.c', 'f2.c'], env.SCCS()) env.SourceCode('no_source.c', None)
-
- env.subst(input, [raw, target, source, conv])
-
Performs construction variable interpolation
on the specified string or sequence argument
input.
By default, leading or trailing white space will be removed from the result. and all sequences of white space will be compressed to a single space character. Additionally, any $( and $) character sequences will be stripped from the returned string, The optional raw argument may be set to 1 if you want to preserve white space and $(-$) sequences. The raw argument may be set to 2 if you want to strip all characters between any $( and $) pairs (as is done for signature calculation).
If the input is a sequence (list or tuple), the individual elements of the sequence will be expanded, and the results will be returned as a list.
The optional target and source keyword arguments must be set to lists of target and source nodes, respectively, if you want the $TARGET, $TARGETS, $SOURCE and $SOURCES to be available for expansion. This is usually necessary if you are calling env.subst() from within a Python function used as an SCons action.
Returned string values or sequence elements are converted to their string representation by default. The optional conv argument may specify a conversion function that will be used in place of the default. For example, if you want Python objects (including SCons Nodes) to be returned as Python objects, you can use the Python lambda idiom to pass in an unnamed function that simply returns its unconverted argument.
Example:
-
print env.subst("The C compiler is: $CC") def compile(target, source, env): sourceDir = env.subst("${SOURCE.srcdir}", target=target, source=source) source_nodes = env.subst('$EXPAND_TO_NODELIST', conv=lambda x: x)
-
- SourceSignatures(type)
- env.SourceSignatures(type)
-
Note: Although it is not yet officially deprecated,
use of this function is discouraged.
See the
Decider()
function for a more flexible and straightforward way
to configure SCons' decision-making.
The SourceSignatures() function tells scons how to decide if a source file (a file that is not built from any other files) has changed since the last time it was used to build a particular target file. Legal values are MD5 or timestamp.
If the environment method is used, the specified type of source signature is only used when deciding whether targets built with that environment are up-to-date or must be rebuilt. If the global function is used, the specified type of source signature becomes the default used for all decisions about whether targets are up-to-date.
MD5 means scons decides that a source file has changed if the MD5 checksum of its contents has changed since the last time it was used to rebuild a particular target file.
timestamp means scons decides that a source file has changed if its timestamp (modification time) has changed since the last time it was used to rebuild a particular target file. (Note that although this is similar to the behavior of Make, by default it will also rebuild if the dependency is older than the last time it was used to rebuild the target file.)
There is no different between the two behaviors for Python Value() node objects.
MD5 signatures take longer to compute, but are more accurate than timestamp signatures. The default value is MD5.
Note that the default TargetSignatures() setting (see below) is to use this SourceSignatures() setting for any target files that are used to build other target files. Consequently, changing the value of SourceSignatures() will, by default, affect the up-to-date decision for all files in the build (or all files built with a specific construction environment when env.SourceSignatures() is used).
- Split(arg)
- env.Split(arg)
-
Returns a list of file names or other objects.
If arg is a string,
it will be split on strings of white-space characters
within the string,
making it easier to write long lists of file names.
If arg is already a list,
the list will be returned untouched.
If arg is any other type of object,
it will be returned as a list
containing just the object.
Example:
-
files = Split("f1.c f2.c f3.c") files = env.Split("f4.c f5.c f6.c") files = Split(""" f7.c f8.c f9.c """)
-
- Tag(node, tags)
-
Annotates file or directory Nodes with
information about how the
Package()
Builder should package those files or directories.
All tags are optional.
Examples:
-
# makes sure the built library will be installed with 0644 file # access mode Tag( Library( 'lib.c' ), UNIX_ATTR="0644" ) # marks file2.txt to be a documentation file Tag( 'file2.txt', DOC )
-
- TargetSignatures(type)
- env.TargetSignatures(type)
-
Note: Although it is not yet officially deprecated,
use of this function is discouraged.
See the
Decider()
function for a more flexible and straightforward way
to configure SCons' decision-making.
The TargetSignatures() function tells scons how to decide if a target file (a file that is built from any other files) has changed since the last time it was used to build some other target file. Legal values are build; content (or its synonym MD5); timestamp; or source.
If the environment method is used, the specified type of target signature is only used for targets built with that environment. If the global function is used, the specified type of signature becomes the default used for all target files that don't have an explicit target signature type specified for their environments.
content (or its synonym MD5) means scons decides that a target file has changed if the MD5 checksum of its contents has changed since the last time it was used to rebuild some other target file. This means scons will open up MD5 sum the contents of target files after they're built, and may decide that it does not need to rebuild "downstream" target files if a file was rebuilt with exactly the same contents as the last time.
timestamp means scons decides that a target file has changed if its timestamp (modification time) has changed since the last time it was used to rebuild some other target file. (Note that although this is similar to the behavior of Make, by default it will also rebuild if the dependency is older than the last time it was used to rebuild the target file.)
source means scons decides that a target file has changed as specified by the corresponding SourceSignatures() setting (MD5 or timestamp). This means that scons will treat all input files to a target the same way, regardless of whether they are source files or have been built from other files.
build means scons decides that a target file has changed if it has been rebuilt in this invocation or if its content or timestamp have changed as specified by the corresponding SourceSignatures() setting. This "propagates" the status of a rebuilt file so that other "downstream" target files will always be rebuilt, even if the contents or the timestamp have not changed.
build signatures are fastest because content (or MD5) signatures take longer to compute, but are more accurate than timestamp signatures, and can prevent unnecessary "downstream" rebuilds when a target file is rebuilt to the exact same contents as the previous build. The source setting provides the most consistent behavior when other target files may be rebuilt from both source and target input files. The default value is source.
Because the default setting is source, using SourceSignatures() is generally preferable to TargetSignatures(), so that the up-to-date decision will be consistent for all files (or all files built with a specific construction environment). Use of TargetSignatures() provides specific control for how built target files affect their "downstream" dependencies.
- Tool(string[,toolpath, **kw])
-
Returns a callable object
that can be used to initialize
a construction environment using the
tools keyword of the Environment() method.
The object may be called with a construction
environment as an argument,
in which case the object will
add the necessary variables
to the construction environment
and the name of the tool will be added to the
$TOOLS
construction variable.
Additional keyword arguments are passed to the tool's generate() method.
Examples:
-
env = Environment(tools = [ Tool('msvc') ]) env = Environment() t = Tool('msvc') t(env) # adds 'msvc' to the TOOLS variable u = Tool('opengl', toolpath = ['tools']) u(env) # adds 'opengl' to the TOOLS variable
-
- env.Tool(string[,toolpath, **kw])
-
Applies the callable object for the specified tool
string
to the environment through which the method was called.
Additional keyword arguments are passed to the tool's generate() method.
-
env.Tool('gcc') env.Tool('opengl', toolpath = ['build/tools'])
-
- Value(value, [built_value])
- env.Value(value, [built_value])
-
Returns a Node object representing the specified Python value. Value
Nodes can be used as dependencies of targets. If the result of
calling
str(value)
changes between SCons runs, any targets depending on
Value(value)
will be rebuilt.
(This is true even when using timestamps to decide if
files are up-to-date.)
When using timestamp source signatures, Value Nodes'
timestamps are equal to the system time when the Node is created.
The returned Value Node object has a write() method that can be used to "build" a Value Node by setting a new value. The optional built_value argument can be specified when the Value Node is created to indicate the Node should already be considered "built." There is a corresponding read() method that will return the built value of the Node.
Examples:
-
env = Environment() def create(target, source, env): # A function that will write a 'prefix=$SOURCE' # string into the file name specified as the # $TARGET. f = open(str(target[0]), 'wb') f.write('prefix=' + source[0].get_contents()) # Fetch the prefix= argument, if any, from the command # line, and use /usr/local as the default. prefix = ARGUMENTS.get('prefix', '/usr/local') # Attach a .Config() builder for the above function action # to the construction environment. env['BUILDERS']['Config'] = Builder(action = create) env.Config(target = 'package-config', source = Value(prefix)) def build_value(target, source, env): # A function that "builds" a Python Value by updating # the the Python value with the contents of the file # specified as the source of the Builder call ($SOURCE). target[0].write(source[0].get_contents()) output = env.Value('before') input = env.Value('after') # Attach a .UpdateValue() builder for the above function # action to the construction environment. env['BUILDERS']['UpdateValue'] = Builder(action = build_value) env.UpdateValue(target = Value(output), source = Value(input))
-
- VariantDir(variant_dir, src_dir, [duplicate])
- env.VariantDir(variant_dir, src_dir, [duplicate])
-
Use the
VariantDir()
function to create a copy of your sources in another location:
if a name under
variant_dir
is not found but exists under
src_dir,
the file or directory is copied to
variant_dir.
Target files can be built in a different directory
than the original sources by simply refering to the sources (and targets)
within the variant tree.
VariantDir() can be called multiple times with the same src_dir to set up multiple builds with different options (variants). The src_dir location must be in or underneath the SConstruct file's directory, and variant_dir may not be underneath src_dir.
The default behavior is for scons to physically duplicate the source files in the variant tree. Thus, a build performed in the variant tree is guaranteed to be identical to a build performed in the source tree even if intermediate source files are generated during the build, or preprocessors or other scanners search for included files relative to the source file, or individual compilers or other invoked tools are hard-coded to put derived files in the same directory as source files.
If possible on the platform, the duplication is performed by linking rather than copying; see also the --duplicate command-line option. Moreover, only the files needed for the build are duplicated; files and directories that are not used are not present in variant_dir.
Duplicating the source tree may be disabled by setting the duplicate argument to 0 (zero). This will cause scons to invoke Builders using the path names of source files in src_dir and the path names of derived files within variant_dir. This is always more efficient than duplicate=1, and is usually safe for most builds (but see above for cases that may cause problems).
Note that VariantDir() works most naturally with a subsidiary SConscript file. However, you would then call the subsidiary SConscript file not in the source directory, but in the variant_dir , regardless of the value of duplicate. This is how you tell scons which variant of a source tree to build:
-
# run src/SConscript in two variant directories VariantDir('build/variant1', 'src') SConscript('build/variant1/SConscript') VariantDir('build/variant2', 'src') SConscript('build/variant2/SConscript')
-
-
See also the
SConscript()
function, described above,
for another way to specify a variant directory
in conjunction with calling a subsidiary SConscript file.
Examples:
-
# use names in the build directory, not the source directory VariantDir('build', 'src', duplicate=0) Program('build/prog', 'build/source.c')
-
# this builds both the source and docs in a separate subtree VariantDir('build', '.', duplicate=0) SConscript(dirs=['build/src','build/doc'])
-
# same as previous example, but only uses SConscript SConscript(dirs='src', variant_dir='build/src', duplicate=0) SConscript(dirs='doc', variant_dir='build/doc', duplicate=0)
-
- WhereIs(program, [path, pathext, reject])
- env.WhereIs(program, [path, pathext, reject])
-
Searches for the specified executable program, returning the full path name to the program if it is found, and returning None if not. Searches the specified path, the value of the calling environment's PATH (env['ENV']['PATH']), or the user's current external PATH (os.environ['PATH']) by default. On Windows systems, searches for executable programs with any of the file extensions listed in the specified pathext, the calling environment's PATHEXT (env['ENV']['PATHEXT']) or the user's current PATHEXT (os.environ['PATHEXT']) by default. Will not select any path name or names in the specified reject list, if any.
SConscript Variables
In addition to the global functions and methods, scons supports a number of Python variables that can be used in SConscript files to affect how you want the build to be performed. These variables may be accessed from custom Python modules that you import into an SConscript file by adding the following to the Python module:
-
from SCons.Script import *
- ARGLIST
-
A list
keyword=value
arguments specified on the command line.
Each element in the list is a tuple
containing the
(keyword,value)
of the argument.
The separate
keyword
and
value
elements of the tuple
can be accessed by
subscripting for element
[0]
and
[1]
of the tuple, respectively.
Example:
-
print "first keyword, value =", ARGLIST[0][0], ARGLIST[0][1] print "second keyword, value =", ARGLIST[1][0], ARGLIST[1][1] third_tuple = ARGLIST[2] print "third keyword, value =", third_tuple[0], third_tuple[1] for key, value in ARGLIST: # process key and value
-
- ARGUMENTS
-
A dictionary of all the
keyword=value
arguments specified on the command line.
The dictionary is not in order,
and if a given keyword has
more than one value assigned to it
on the command line,
the last (right-most) value is
the one in the
ARGUMENTS
dictionary.
Example:
-
if ARGUMENTS.get('debug', 0): env = Environment(CCFLAGS = '-g') else: env = Environment()
-
- BUILD_TARGETS
-
A list of the targets which
scons
will actually try to build,
regardless of whether they were specified on
the command line or via the
Default()
function or method.
The elements of this list may be strings
or
nodes, so you should run the list through the Python
str
function to make sure any Node path names
are converted to strings.
Because this list may be taken from the list of targets specified using the Default() function or method, the contents of the list may change on each successive call to Default(). See the DEFAULT_TARGETS list, below, for additional information.
Example:
-
if 'foo' in BUILD_TARGETS: print "Don't forget to test the `foo' program!" if 'special/program' in BUILD_TARGETS: SConscript('special')
-
-
Note that the
BUILD_TARGETS
list only contains targets expected listed
on the command line or via calls to the
Default()
function or method.
It does
not
contain all dependent targets that will be built as
a result of making the sure the explicitly-specified
targets are up to date.
- COMMAND_LINE_TARGETS
-
A list of the targets explicitly specified on
the command line.
If there are no targets specified on the command line,
the list is empty.
This can be used, for example,
to take specific actions only
when a certain target or targets
is explicitly being built.
Example:
-
if 'foo' in COMMAND_LINE_TARGETS: print "Don't forget to test the `foo' program!" if 'special/program' in COMMAND_LINE_TARGETS: SConscript('special')
-
- DEFAULT_TARGETS
-
A list of the target
nodes
that have been specified using the
Default()
function or method.
The elements of the list are nodes,
so you need to run them through the Python
str
function to get at the path name for each Node.
Example:
-
print str(DEFAULT_TARGETS[0]) if 'foo' in map(str, DEFAULT_TARGETS): print "Don't forget to test the `foo' program!"
-
-
The contents of the
DEFAULT_TARGETS
list change on on each successive call to the
Default()
function:
-
print map(str, DEFAULT_TARGETS) # originally [] Default('foo') print map(str, DEFAULT_TARGETS) # now a node ['foo'] Default('bar') print map(str, DEFAULT_TARGETS) # now a node ['foo', 'bar'] Default(None) print map(str, DEFAULT_TARGETS) # back to []
-
-
Consequently, be sure to use
DEFAULT_TARGETS
only after you've made all of your
Default()
calls,
or else simply be careful of the order
of these statements in your SConscript files
so that you don't look for a specific
default target before it's actually been added to the list.
Construction Variables
A construction environment has an associated dictionary of construction variables that are used by built-in or user-supplied build rules. Construction variables must follow the same rules for Python identifiers: the initial character must be an underscore or letter, followed by any number of underscores, letters, or digits.A number of useful construction variables are automatically defined by scons for each supported platform, and additional construction variables can be defined by the user. The following is a list of the automatically defined construction variables:
- AR
-
The static library archiver.
- ARCHITECTURE
-
Specifies the system architecture for which
the package is being built.
The default is the system architecture
of the machine on which SCons is running.
This is used to fill in the
Architecture:
field in an Ipkg
control file,
and as part of the name of a generated RPM file.
- ARCOM
-
The command line used to generate a static library from object files.
- ARCOMSTR
-
The string displayed when an object file
is generated from an assembly-language source file.
If this is not set, then $ARCOM (the command line) is displayed.
-
env = Environment(ARCOMSTR = "Archiving $TARGET")
-
- ARFLAGS
-
General options passed to the static library archiver.
- AS
-
The assembler.
- ASCOM
-
The command line used to generate an object file
from an assembly-language source file.
- ASCOMSTR
-
The string displayed when an object file
is generated from an assembly-language source file.
If this is not set, then $ASCOM (the command line) is displayed.
-
env = Environment(ASCOMSTR = "Assembling $TARGET")
-
- ASFLAGS
-
General options passed to the assembler.
- ASPPCOM
-
The command line used to assemble an assembly-language
source file into an object file
after first running the file through the C preprocessor.
Any options specified
in the $ASFLAGS and $CPPFLAGS construction variables
are included on this command line.
- ASPPCOMSTR
-
The string displayed when an object file
is generated from an assembly-language source file
after first running the file through the C preprocessor.
If this is not set, then $ASPPCOM (the command line) is displayed.
-
env = Environment(ASPPCOMSTR = "Assembling $TARGET")
-
- ASPPFLAGS
-
General options when an assembling an assembly-language
source file into an object file
after first running the file through the C preprocessor.
The default is to use the value of $ASFLAGS.
- BIBTEX
-
The bibliography generator for the TeX formatter and typesetter and the
LaTeX structured formatter and typesetter.
- BIBTEXCOM
-
The command line used to call the bibliography generator for the
TeX formatter and typesetter and the LaTeX structured formatter and
typesetter.
- BIBTEXCOMSTR
-
The string displayed when generating a bibliography
for TeX or LaTeX.
If this is not set, then $BIBTEXCOM (the command line) is displayed.
-
env = Environment(BIBTEXCOMSTR = "Generating bibliography $TARGET")
-
- BIBTEXFLAGS
-
General options passed to the bibliography generator for the TeX formatter
and typesetter and the LaTeX structured formatter and typesetter.
- BITKEEPER
-
The BitKeeper executable.
- BITKEEPERCOM
-
The command line for
fetching source files using BitKeeper.
- BITKEEPERCOMSTR
-
The string displayed when fetching
a source file using BitKeeper.
If this is not set, then $BITKEEPERCOM
(the command line) is displayed.
- BITKEEPERGET
-
The command ($BITKEEPER) and subcommand
for fetching source files using BitKeeper.
- BITKEEPERGETFLAGS
-
Options that are passed to the BitKeeper
get
subcommand.
- BUILDERS
-
A dictionary mapping the names of the builders
available through this environment
to underlying Builder objects.
Builders named
Alias, CFile, CXXFile, DVI, Library, Object, PDF, PostScript, and Program
are available by default.
If you initialize this variable when an
Environment is created:
-
env = Environment(BUILDERS = {'NewBuilder' : foo})
-
-
the default Builders will no longer be available.
To use a new Builder object in addition to the default Builders,
add your new Builder object like this:
-
env = Environment() env.Append(BUILDERS = {'NewBuilder' : foo})
-
-
or this:
-
env = Environment() env['BUILDERS]['NewBuilder'] = foo
-
- CC
-
The C compiler.
- CCCOM
-
The command line used to compile a C source file to a (static) object
file. Any options specified in the $CFLAGS, $CCFLAGS and
$CPPFLAGS construction variables are included on this command
line.
- CCCOMSTR
-
The string displayed when a C source file
is compiled to a (static) object file.
If this is not set, then $CCCOM (the command line) is displayed.
-
env = Environment(CCCOMSTR = "Compiling static object $TARGET")
-
- CCFLAGS
-
General options that are passed to the C and C++ compilers.
- CCPCHFLAGS
-
Options added to the compiler command line
to support building with precompiled headers.
The default value expands expands to the appropriate
Microsoft Visual C++ command-line options
when the $PCH construction variable is set.
- CCPDBFLAGS
-
Options added to the compiler command line
to support storing debugging information in a
Microsoft Visual C++ PDB file.
The default value expands expands to appropriate
Microsoft Visual C++ command-line options
when the $PDB construction variable is set.
The Visual C++ compiler option that SCons uses by default to generate PDB information is /Z7. This works correctly with parallel (-j) builds because it embeds the debug information in the intermediate object files, as opposed to sharing a single PDB file between multiple object files. This is also the only way to get debug information embedded into a static library. Using the /Zi instead may yield improved link-time performance, although parallel builds will no longer work.
You can generate PDB files with the /Zi switch by overriding the default $CCPDBFLAGS variable as follows:
-
env['CCPDBFLAGS'] = ['${(PDB and "/Zi /Fd%s" % File(PDB)) or ""}']
-
-
An alternative would be to use the /Zi
to put the debugging information in a separate .pdb
file for each object file by overriding
the $CCPDBFLAGS variable as follows:
-
env['CCPDBFLAGS'] = '/Zi /Fd${TARGET}.pdb'
-
- CCVERSION
-
The version number of the C compiler.
This may or may not be set,
depending on the specific C compiler being used.
- CFILESUFFIX
-
The suffix for C source files.
This is used by the internal CFile builder
when generating C files from Lex (.l) or YACC (.y) input files.
The default suffix, of course, is
.c
(lower case).
On case-insensitive systems (like Windows),
SCons also treats
.C
(upper case) files
as C files.
- CFLAGS
-
General options that are passed to the C compiler (C only; not C++).
- CHANGE_SPECFILE
-
A hook for modifying the file that controls the packaging build
(the .spec for RPM,
the control for Ipkg,
the .wxs for MSI).
If set, the function will be called
after the SCons template for the file has been written.
XXX
- CHANGED_SOURCES
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- CHANGED_TARGETS
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- CHANGELOG
-
The name of a file containing the change log text
to be included in the package.
This is included as the
%changelog
section of the RPM
.spec file.
- _concat
-
A function used to produce variables like $_CPPINCFLAGS. It takes
four or five
arguments: a prefix to concatenate onto each element, a list of
elements, a suffix to concatenate onto each element, an environment
for variable interpolation, and an optional function that will be
called to transform the list before concatenation.
-
env['_CPPINCFLAGS'] = '$( ${_concat(INCPREFIX, CPPPATH, INCSUFFIX, __env__, RDirs)} $)',
-
- CONFIGUREDIR
-
The name of the directory in which
Configure context test files are written.
The default is
.sconf_temp
in the top-level directory
containing the
SConstruct
file.
- CONFIGURELOG
-
The name of the Configure context log file.
The default is
config.log
in the top-level directory
containing the
SConstruct
file.
- _CPPDEFFLAGS
-
An automatically-generated construction variable
containing the C preprocessor command-line options
to define values.
The value of $_CPPDEFFLAGS is created
by appending $CPPDEFPREFIX and $CPPDEFSUFFIX
to the beginning and end
of each definition in $CPPDEFINES.
- CPPDEFINES
-
A platform independent specification of C preprocessor definitions.
The definitions will be added to command lines
through the automatically-generated
$_CPPDEFFLAGS construction variable (see above),
which is constructed according to
the type of value of $CPPDEFINES:
If $CPPDEFINES is a string, the values of the $CPPDEFPREFIX and $CPPDEFSUFFIX construction variables will be added to the beginning and end.
-
# Will add -Dxyz to POSIX compiler command lines, # and /Dxyz to Microsoft Visual C++ command lines. env = Environment(CPPDEFINES='xyz')
-
-
If $CPPDEFINES is a list,
the values of the
$CPPDEFPREFIX and $CPPDEFSUFFIX
construction variables
will be appended to the beginning and end
of each element in the list.
If any element is a list or tuple,
then the first item is the name being
defined and the second item is its value:
-
# Will add -DB=2 -DA to POSIX compiler command lines, # and /DB=2 /DA to Microsoft Visual C++ command lines. env = Environment(CPPDEFINES=[('B', 2), 'A'])
-
-
If $CPPDEFINES is a dictionary,
the values of the
$CPPDEFPREFIX and $CPPDEFSUFFIX
construction variables
will be appended to the beginning and end
of each item from the dictionary.
The key of each dictionary item
is a name being defined
to the dictionary item's corresponding value;
if the value is
None,
then the name is defined without an explicit value.
Note that the resulting flags are sorted by keyword
to ensure that the order of the options on the
command line is consistent each time
scons
is run.
-
# Will add -DA -DB=2 to POSIX compiler command lines, # and /DA /DB=2 to Microsoft Visual C++ command lines. env = Environment(CPPDEFINES={'B':2, 'A':None})
-
- CPPDEFPREFIX
-
The prefix used to specify preprocessor definitions
on the C compiler command line.
This will be appended to the beginning of each definition
in the $CPPDEFINES construction variable
when the $_CPPDEFFLAGS variable is automatically generated.
- CPPDEFSUFFIX
-
The suffix used to specify preprocessor definitions
on the C compiler command line.
This will be appended to the end of each definition
in the $CPPDEFINES construction variable
when the $_CPPDEFFLAGS variable is automatically generated.
- CPPFLAGS
-
User-specified C preprocessor options.
These will be included in any command that uses the C preprocessor,
including not just compilation of C and C++ source files
via the $CCCOM,
$SHCCCOM,
$CXXCOM and
$SHCXXCOM command lines,
but also the $FORTRANPPCOM,
$SHFORTRANPPCOM,
$F77PPCOM and
$SHF77PPCOM command lines
used to compile a Fortran source file,
and the $ASPPCOM command line
used to assemble an assembly language source file,
after first running each file through the C preprocessor.
Note that this variable does
not
contain
-I
(or similar) include search path options
that scons generates automatically from $CPPPATH.
See $_CPPINCFLAGS, below,
for the variable that expands to those options.
- _CPPINCFLAGS
-
An automatically-generated construction variable
containing the C preprocessor command-line options
for specifying directories to be searched for include files.
The value of $_CPPINCFLAGS is created
by appending $INCPREFIX and $INCSUFFIX
to the beginning and end
of each directory in $CPPPATH.
- CPPPATH
-
The list of directories that the C preprocessor will search for include
directories. The C/C++ implicit dependency scanner will search these
directories for include files. Don't explicitly put include directory
arguments in CCFLAGS or CXXFLAGS because the result will be non-portable
and the directories will not be searched by the dependency scanner. Note:
directory names in CPPPATH will be looked-up relative to the SConscript
directory when they are used in a command. To force
scons
to look-up a directory relative to the root of the source tree use #:
-
env = Environment(CPPPATH='#/include')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
include = Dir('include') env = Environment(CPPPATH=include)
-
-
The directory list will be added to command lines
through the automatically-generated
$_CPPINCFLAGS
construction variable,
which is constructed by
appending the values of the
$INCPREFIX and $INCSUFFIX
construction variables
to the beginning and end
of each directory in $CPPPATH.
Any command lines you define that need
the CPPPATH directory list should
include $_CPPINCFLAGS:
-
env = Environment(CCCOM="my_compiler $_CPPINCFLAGS -c -o $TARGET $SOURCE")
-
- CPPSUFFIXES
-
The list of suffixes of files that will be scanned
for C preprocessor implicit dependencies
(#include lines).
The default list is:
-
[".c", ".C", ".cxx", ".cpp", ".c++", ".cc", ".h", ".H", ".hxx", ".hpp", ".hh", ".F", ".fpp", ".FPP", ".m", ".mm", ".S", ".spp", ".SPP"]
-
- CVS
-
The CVS executable.
- CVSCOFLAGS
-
Options that are passed to the CVS checkout subcommand.
- CVSCOM
-
The command line used to
fetch source files from a CVS repository.
- CVSCOMSTR
-
The string displayed when fetching
a source file from a CVS repository.
If this is not set, then $CVSCOM
(the command line) is displayed.
- CVSFLAGS
-
General options that are passed to CVS.
By default, this is set to
-d $CVSREPOSITORY
to specify from where the files must be fetched.
- CVSREPOSITORY
-
The path to the CVS repository.
This is referenced in the default
$CVSFLAGS value.
- CXX
-
The C++ compiler.
- CXXCOM
-
The command line used to compile a C++ source file to an object file.
Any options specified in the $CXXFLAGS and
$CPPFLAGS construction variables
are included on this command line.
- CXXCOMSTR
-
The string displayed when a C++ source file
is compiled to a (static) object file.
If this is not set, then $CXXCOM (the command line) is displayed.
-
env = Environment(CXXCOMSTR = "Compiling static object $TARGET")
-
- CXXFILESUFFIX
-
The suffix for C++ source files.
This is used by the internal CXXFile builder
when generating C++ files from Lex (.ll) or YACC (.yy) input files.
The default suffix is
.cc.
SCons also treats files with the suffixes
.cpp,
.cxx,
.c++,
and
.C++
as C++ files,
and files with
.mm
suffixes as Objective C++ files.
On case-sensitive systems (Linux, UNIX, and other POSIX-alikes),
SCons also treats
.C
(upper case) files
as C++ files.
- CXXFLAGS
-
General options that are passed to the C++ compiler.
By default, this includes the value of $CCFLAGS,
so that setting $CCFLAGS affects both C and C++ compilation.
If you want to add C++-specific flags,
you must set or override the value of $CXXFLAGS.
- CXXVERSION
-
The version number of the C++ compiler.
This may or may not be set,
depending on the specific C++ compiler being used.
- DESCRIPTION
-
A long description of the project being packaged.
This is included in the relevant section
of the file that controls the packaging build.
- DESCRIPTION_lang
-
A language-specific long description for
the specified lang.
This is used to populate a
%description -l
section of an RPM
.spec file.
- Dir
-
A function that converts a string
into a Dir instance relative to the target being built.
- Dirs
-
A function that converts a list of strings
into a list of Dir instances relative to the target being built.
- DSUFFIXES
-
The list of suffixes of files that will be scanned
for imported D package files.
The default list is:
-
['.d']
-
- DVIPDF
-
The TeX DVI file to PDF file converter.
- DVIPDFCOM
-
The command line used to convert TeX DVI files into a PDF file.
- DVIPDFCOMSTR
-
The string displayed when a TeX DVI file
is converted into a PDF file.
If this is not set, then $DVIPDFCOM (the command line) is displayed.
- DVIPDFFLAGS
-
General options passed to the TeX DVI file to PDF file converter.
- DVIPS
-
The TeX DVI file to PostScript converter.
- DVIPSFLAGS
-
General options passed to the TeX DVI file to PostScript converter.
- ENV
-
A dictionary of environment variables
to use when invoking commands. When
$ENV is used in a command all list
values will be joined using the path separator and any other non-string
values will simply be coerced to a string.
Note that, by default,
scons
does
not
propagate the environment in force when you
execute
scons
to the commands used to build target files.
This is so that builds will be guaranteed
repeatable regardless of the environment
variables set at the time
scons
is invoked.
If you want to propagate your environment variables to the commands executed to build target files, you must do so explicitly:
-
import os env = Environment(ENV = os.environ)
-
-
Note that you can choose only to propagate
certain environment variables.
A common example is
the system
PATH
environment variable,
so that
scons
uses the same utilities
as the invoking shell (or other process):
-
import os env = Environment(ENV = {'PATH' : os.environ['PATH']})
-
- ESCAPE
-
A function that will be called to escape shell special characters in
command lines. The function should take one argument: the command line
string to escape; and should return the escaped command line.
- F77
-
The Fortran 77 compiler.
You should normally set the $FORTRAN variable,
which specifies the default Fortran compiler
for all Fortran versions.
You only need to set $F77 if you need to use a specific compiler
or compiler version for Fortran 77 files.
- F77COM
-
The command line used to compile a Fortran 77 source file to an object file.
You only need to set $F77COM if you need to use a specific
command line for Fortran 77 files.
You should normally set the $FORTRANCOM variable,
which specifies the default command line
for all Fortran versions.
- F77COMSTR
-
The string displayed when a Fortran 77 source file
is compiled to an object file.
If this is not set, then $F77COM or $FORTRANCOM
(the command line) is displayed.
- F77FILESUFFIXES
-
The list of file extensions for which the F77 dialect will be used. By
default, this is ['.f77']
- F77FLAGS
-
General user-specified options that are passed to the Fortran 77 compiler.
Note that this variable does
not
contain
-I
(or similar) include search path options
that scons generates automatically from $F77PATH.
See
$_F77INCFLAGS
below,
for the variable that expands to those options.
You only need to set $F77FLAGS if you need to define specific
user options for Fortran 77 files.
You should normally set the $FORTRANFLAGS variable,
which specifies the user-specified options
passed to the default Fortran compiler
for all Fortran versions.
- _F77INCFLAGS
-
An automatically-generated construction variable
containing the Fortran 77 compiler command-line options
for specifying directories to be searched for include files.
The value of $_F77INCFLAGS is created
by appending $INCPREFIX and $INCSUFFIX
to the beginning and end
of each directory in $F77PATH.
- F77PATH
-
The list of directories that the Fortran 77 compiler will search for include
directories. The implicit dependency scanner will search these
directories for include files. Don't explicitly put include directory
arguments in $F77FLAGS because the result will be non-portable
and the directories will not be searched by the dependency scanner. Note:
directory names in $F77PATH will be looked-up relative to the SConscript
directory when they are used in a command. To force
scons
to look-up a directory relative to the root of the source tree use #:
You only need to set $F77PATH if you need to define a specific
include path for Fortran 77 files.
You should normally set the $FORTRANPATH variable,
which specifies the include path
for the default Fortran compiler
for all Fortran versions.
-
env = Environment(F77PATH='#/include')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
include = Dir('include') env = Environment(F77PATH=include)
-
-
The directory list will be added to command lines
through the automatically-generated
$_F77INCFLAGS
construction variable,
which is constructed by
appending the values of the
$INCPREFIX and $INCSUFFIX
construction variables
to the beginning and end
of each directory in $F77PATH.
Any command lines you define that need
the F77PATH directory list should
include $_F77INCFLAGS:
-
env = Environment(F77COM="my_compiler $_F77INCFLAGS -c -o $TARGET $SOURCE")
-
- F77PPCOM
-
The command line used to compile a Fortran 77 source file to an object file
after first running the file through the C preprocessor.
Any options specified in the $F77FLAGS and $CPPFLAGS construction variables
are included on this command line.
You only need to set $F77PPCOM if you need to use a specific
C-preprocessor command line for Fortran 77 files.
You should normally set the $FORTRANPPCOM variable,
which specifies the default C-preprocessor command line
for all Fortran versions.
- F77PPCOMSTR
-
The string displayed when a Fortran 77 source file
is compiled to an object file
after first running the file through the C preprocessor.
If this is not set, then $F77PPCOM or $FORTRANPPCOM
(the command line) is displayed.
- F77PPFILESUFFIXES
-
The list of file extensions for which the compilation + preprocessor pass for
F77 dialect will be used. By default, this is empty
- F90
-
The Fortran 90 compiler.
You should normally set the $FORTRAN variable,
which specifies the default Fortran compiler
for all Fortran versions.
You only need to set $F90 if you need to use a specific compiler
or compiler version for Fortran 90 files.
- F90COM
-
The command line used to compile a Fortran 90 source file to an object file.
You only need to set $F90COM if you need to use a specific
command line for Fortran 90 files.
You should normally set the $FORTRANCOM variable,
which specifies the default command line
for all Fortran versions.
- F90COMSTR
-
The string displayed when a Fortran 90 source file
is compiled to an object file.
If this is not set, then $F90COM or $FORTRANCOM
(the command line) is displayed.
- F90FILESUFFIXES
-
The list of file extensions for which the F90 dialect will be used. By
default, this is ['.f90']
- F90FLAGS
-
General user-specified options that are passed to the Fortran 90 compiler.
Note that this variable does
not
contain
-I
(or similar) include search path options
that scons generates automatically from $F90PATH.
See
$_F90INCFLAGS
below,
for the variable that expands to those options.
You only need to set $F90FLAGS if you need to define specific
user options for Fortran 90 files.
You should normally set the $FORTRANFLAGS variable,
which specifies the user-specified options
passed to the default Fortran compiler
for all Fortran versions.
- _F90INCFLAGS
-
An automatically-generated construction variable
containing the Fortran 90 compiler command-line options
for specifying directories to be searched for include files.
The value of $_F90INCFLAGS is created
by appending $INCPREFIX and $INCSUFFIX
to the beginning and end
of each directory in $F90PATH.
- F90PATH
-
The list of directories that the Fortran 90 compiler will search for include
directories. The implicit dependency scanner will search these
directories for include files. Don't explicitly put include directory
arguments in $F90FLAGS because the result will be non-portable
and the directories will not be searched by the dependency scanner. Note:
directory names in $F90PATH will be looked-up relative to the SConscript
directory when they are used in a command. To force
scons
to look-up a directory relative to the root of the source tree use #:
You only need to set $F90PATH if you need to define a specific
include path for Fortran 90 files.
You should normally set the $FORTRANPATH variable,
which specifies the include path
for the default Fortran compiler
for all Fortran versions.
-
env = Environment(F90PATH='#/include')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
include = Dir('include') env = Environment(F90PATH=include)
-
-
The directory list will be added to command lines
through the automatically-generated
$_F90INCFLAGS
construction variable,
which is constructed by
appending the values of the
$INCPREFIX and $INCSUFFIX
construction variables
to the beginning and end
of each directory in $F90PATH.
Any command lines you define that need
the F90PATH directory list should
include $_F90INCFLAGS:
-
env = Environment(F90COM="my_compiler $_F90INCFLAGS -c -o $TARGET $SOURCE")
-
- F90PPCOM
-
The command line used to compile a Fortran 90 source file to an object file
after first running the file through the C preprocessor.
Any options specified in the $F90FLAGS and $CPPFLAGS construction variables
are included on this command line.
You only need to set $F90PPCOM if you need to use a specific
C-preprocessor command line for Fortran 90 files.
You should normally set the $FORTRANPPCOM variable,
which specifies the default C-preprocessor command line
for all Fortran versions.
- F90PPCOMSTR
-
The string displayed when a Fortran 90 source file
is compiled after first running the file through the C preprocessor.
If this is not set, then $F90PPCOM or $FORTRANPPCOM
(the command line) is displayed.
- F90PPFILESUFFIXES
-
The list of file extensions for which the compilation + preprocessor pass for
F90 dialect will be used. By default, this is empty
- F95
-
The Fortran 95 compiler.
You should normally set the $FORTRAN variable,
which specifies the default Fortran compiler
for all Fortran versions.
You only need to set $F95 if you need to use a specific compiler
or compiler version for Fortran 95 files.
- F95COM
-
The command line used to compile a Fortran 95 source file to an object file.
You only need to set $F95COM if you need to use a specific
command line for Fortran 95 files.
You should normally set the $FORTRANCOM variable,
which specifies the default command line
for all Fortran versions.
- F95COMSTR
-
The string displayed when a Fortran 95 source file
is compiled to an object file.
If this is not set, then $F95COM or $FORTRANCOM
(the command line) is displayed.
- F95FILESUFFIXES
-
The list of file extensions for which the F95 dialect will be used. By
default, this is ['.f95']
- F95FLAGS
-
General user-specified options that are passed to the Fortran 95 compiler.
Note that this variable does
not
contain
-I
(or similar) include search path options
that scons generates automatically from $F95PATH.
See
$_F95INCFLAGS
below,
for the variable that expands to those options.
You only need to set $F95FLAGS if you need to define specific
user options for Fortran 95 files.
You should normally set the $FORTRANFLAGS variable,
which specifies the user-specified options
passed to the default Fortran compiler
for all Fortran versions.
- _F95INCFLAGS
-
An automatically-generated construction variable
containing the Fortran 95 compiler command-line options
for specifying directories to be searched for include files.
The value of $_F95INCFLAGS is created
by appending $INCPREFIX and $INCSUFFIX
to the beginning and end
of each directory in $F95PATH.
- F95PATH
-
The list of directories that the Fortran 95 compiler will search for include
directories. The implicit dependency scanner will search these
directories for include files. Don't explicitly put include directory
arguments in $F95FLAGS because the result will be non-portable
and the directories will not be searched by the dependency scanner. Note:
directory names in $F95PATH will be looked-up relative to the SConscript
directory when they are used in a command. To force
scons
to look-up a directory relative to the root of the source tree use #:
You only need to set $F95PATH if you need to define a specific
include path for Fortran 95 files.
You should normally set the $FORTRANPATH variable,
which specifies the include path
for the default Fortran compiler
for all Fortran versions.
-
env = Environment(F95PATH='#/include')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
include = Dir('include') env = Environment(F95PATH=include)
-
-
The directory list will be added to command lines
through the automatically-generated
$_F95INCFLAGS
construction variable,
which is constructed by
appending the values of the
$INCPREFIX and $INCSUFFIX
construction variables
to the beginning and end
of each directory in $F95PATH.
Any command lines you define that need
the F95PATH directory list should
include $_F95INCFLAGS:
-
env = Environment(F95COM="my_compiler $_F95INCFLAGS -c -o $TARGET $SOURCE")
-
- F95PPCOM
-
The command line used to compile a Fortran 95 source file to an object file
after first running the file through the C preprocessor.
Any options specified in the $F95FLAGS and $CPPFLAGS construction variables
are included on this command line.
You only need to set $F95PPCOM if you need to use a specific
C-preprocessor command line for Fortran 95 files.
You should normally set the $FORTRANPPCOM variable,
which specifies the default C-preprocessor command line
for all Fortran versions.
- F95PPCOMSTR
-
The string displayed when a Fortran 95 source file
is compiled to an object file
after first running the file through the C preprocessor.
If this is not set, then $F95PPCOM or $FORTRANPPCOM
(the command line) is displayed.
- F95PPFILESUFFIXES
-
The list of file extensions for which the compilation + preprocessor pass for
F95 dialect will be used. By default, this is empty
- File
-
A function that converts a string into a File instance relative to the
target being built.
- FORTRAN
-
The default Fortran compiler
for all versions of Fortran.
- FORTRANCOM
-
The command line used to compile a Fortran source file to an object file.
By default, any options specified
in the $FORTRANFLAGS,
$CPPFLAGS,
$_CPPDEFFLAGS,
$_FORTRANMODFLAG, and
$_FORTRANINCFLAGS construction variables
are included on this command line.
- FORTRANCOMSTR
-
The string displayed when a Fortran source file
is compiled to an object file.
If this is not set, then $FORTRANCOM
(the command line) is displayed.
- FORTRANFILESUFFIXES
-
The list of file extensions for which the FORTRAN dialect will be used. By
default, this is ['.f', '.for', '.ftn']
- FORTRANFLAGS
-
General user-specified options that are passed to the Fortran compiler.
Note that this variable does
not
contain
-I
(or similar) include or module search path options
that scons generates automatically from $FORTRANPATH.
See
$_FORTRANINCFLAGS and $_FORTRANMODFLAG,
below,
for the variables that expand those options.
- _FORTRANINCFLAGS
-
An automatically-generated construction variable
containing the Fortran compiler command-line options
for specifying directories to be searched for include
files and module files.
The value of $_FORTRANINCFLAGS is created
by prepending/appending $INCPREFIX and $INCSUFFIX
to the beginning and end
of each directory in $FORTRANPATH.
- FORTRANMODDIR
-
Directory location where the Fortran compiler should place
any module files it generates. This variable is empty, by default. Some
Fortran compilers will internally append this directory in the search path
for module files, as well.
- FORTRANMODDIRPREFIX
-
The prefix used to specify a module directory on the Fortran compiler command
line.
This will be appended to the beginning of the directory
in the $FORTRANMODDIR construction variables
when the $_FORTRANMODFLAG variables is automatically generated.
- FORTRANMODDIRSUFFIX
-
The suffix used to specify a module directory on the Fortran compiler command
line.
This will be appended to the beginning of the directory
in the $FORTRANMODDIR construction variables
when the $_FORTRANMODFLAG variables is automatically generated.
- _FORTRANMODFLAG
-
An automatically-generated construction variable
containing the Fortran compiler command-line option
for specifying the directory location where the Fortran
compiler should place any module files that happen to get
generated during compilation.
The value of $_FORTRANMODFLAG is created
by prepending/appending $FORTRANMODDIRPREFIX and
$FORTRANMODDIRSUFFIX
to the beginning and end of the directory in $FORTRANMODDIR.
- FORTRANMODPREFIX
-
The module file prefix used by the Fortran compiler. SCons assumes that
the Fortran compiler follows the quasi-standard naming convention for
module files of
module_name.mod.
As a result, this variable is left empty, by default. For situations in
which the compiler does not necessarily follow the normal convention,
the user may use this variable. Its value will be appended to every
module file name as scons attempts to resolve dependencies.
- FORTRANMODSUFFIX
-
The module file suffix used by the Fortran compiler. SCons assumes that
the Fortran compiler follows the quasi-standard naming convention for
module files of
module_name.mod.
As a result, this variable is set to ".mod", by default. For situations
in which the compiler does not necessarily follow the normal convention,
the user may use this variable. Its value will be appended to every
module file name as scons attempts to resolve dependencies.
- FORTRANPATH
-
The list of directories that the Fortran compiler will search for
include files and (for some compilers) module files. The Fortran implicit
dependency scanner will search these directories for include files (but
not module files since they are autogenerated and, as such, may not
actually exist at the time the scan takes place). Don't explicitly put
include directory arguments in FORTRANFLAGS because the result will be
non-portable and the directories will not be searched by the dependency
scanner. Note: directory names in FORTRANPATH will be looked-up relative
to the SConscript directory when they are used in a command. To force
scons
to look-up a directory relative to the root of the source tree use #:
-
env = Environment(FORTRANPATH='#/include')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
include = Dir('include') env = Environment(FORTRANPATH=include)
-
-
The directory list will be added to command lines
through the automatically-generated
$_FORTRANINCFLAGS
construction variable,
which is constructed by
appending the values of the
$INCPREFIX and $INCSUFFIX
construction variables
to the beginning and end
of each directory in $FORTRANPATH.
Any command lines you define that need
the FORTRANPATH directory list should
include $_FORTRANINCFLAGS:
-
env = Environment(FORTRANCOM="my_compiler $_FORTRANINCFLAGS -c -o $TARGET $SOURCE")
-
- FORTRANPPCOM
-
The command line used to compile a Fortran source file to an object file
after first running the file through the C preprocessor.
By default, any options specified in the $FORTRANFLAGS,
$CPPFLAGS,
$_CPPDEFFLAGS,
$_FORTRANMODFLAG, and
$_FORTRANINCFLAGS
construction variables are included on this command line.
- FORTRANPPCOMSTR
-
The string displayed when a Fortran source file
is compiled to an object file
after first running the file through the C preprocessor.
If this is not set, then $FORTRANPPCOM
(the command line) is displayed.
- FORTRANPPFILESUFFIXES
-
The list of file extensions for which the compilation + preprocessor pass for
FORTRAN dialect will be used. By default, this is ['.fpp', '.FPP']
- FORTRANSUFFIXES
-
The list of suffixes of files that will be scanned
for Fortran implicit dependencies
(INCLUDE lines and USE statements).
The default list is:
-
[".f", ".F", ".for", ".FOR", ".ftn", ".FTN", ".fpp", ".FPP", ".f77", ".F77", ".f90", ".F90", ".f95", ".F95"]
-
- FRAMEWORKPATH
-
On Mac OS X with gcc,
a list containing the paths to search for frameworks.
Used by the compiler to find framework-style includes like
#include <Fmwk/Header.h>.
Used by the linker to find user-specified frameworks when linking (see
$FRAMEWORKS).
For example:
-
env.AppendUnique(FRAMEWORKPATH='#myframeworkdir')
-
-
will add
-
... -Fmyframeworkdir
-
-
to the compiler and linker command lines.
- _FRAMEWORKPATH
-
On Mac OS X with gcc, an automatically-generated construction variable
containing the linker command-line options corresponding to
$FRAMEWORKPATH.
- FRAMEWORKPATHPREFIX
-
On Mac OS X with gcc, the prefix to be used for the FRAMEWORKPATH entries.
(see $FRAMEWORKPATH).
The default value is
-F.
- FRAMEWORKPREFIX
-
On Mac OS X with gcc,
the prefix to be used for linking in frameworks
(see $FRAMEWORKS).
The default value is
-framework.
- _FRAMEWORKS
-
On Mac OS X with gcc,
an automatically-generated construction variable
containing the linker command-line options
for linking with FRAMEWORKS.
- FRAMEWORKS
-
On Mac OS X with gcc, a list of the framework names to be linked into a
program or shared library or bundle.
The default value is the empty list.
For example:
-
env.AppendUnique(FRAMEWORKS=Split('System Cocoa SystemConfiguration'))
-
-
- FRAMEWORKSFLAGS
-
On Mac OS X with gcc,
general user-supplied frameworks options to be added at
the end of a command
line building a loadable module.
(This has been largely superseded by
the $FRAMEWORKPATH, $FRAMEWORKPATHPREFIX,
$FRAMEWORKPREFIX and $FRAMEWORKS variables
described above.)
- GS
-
The Ghostscript program used to convert PostScript to PDF files.
- GSCOM
-
The Ghostscript command line used to convert PostScript to PDF files.
- GSCOMSTR
-
The string displayed when
Ghostscript is used to convert
a PostScript file to a PDF file.
If this is not set, then $GSCOM (the command line) is displayed.
- GSFLAGS
-
General options passed to the Ghostscript program
when converting PostScript to PDF files.
- HOST_ARCH
-
Sets the host architecture for Visual Studio compiler. If not set,
default to the detected host architecture: note that this may depend
on the python you are using.
This variable must be passed as an argument to the Environment()
constructor; setting it later has no effect.
Valid values are the same as for $TARGET_ARCH.
This is currently only used on Windows, but in the future it will be used on other OSes as well.
- HOST_OS
-
The name of the host operating system used to create the Environment.
If a platform is specified when creating the Environment, then
that Platform's logic will handle setting this value.
This value is immutable, and should not be changed by the user after
the Environment is initialized.
Currently only set for Win32.
- IDLSUFFIXES
-
The list of suffixes of files that will be scanned
for IDL implicit dependencies
(#include or import lines).
The default list is:
-
[".idl", ".IDL"]
-
- IMPLICIT_COMMAND_DEPENDENCIES
-
Controls whether or not SCons will
add implicit dependencies for the commands
executed to build targets.
By default, SCons will add to each target an implicit dependency on the command represented by the first argument on any command line it executes. The specific file for the dependency is found by searching the PATH variable in the ENV environment used to execute the command.
If the construction variable $IMPLICIT_COMMAND_DEPENDENCIES is set to a false value (None, False, 0, etc.), then the implicit dependency will not be added to the targets built with that construction environment.
-
env = Environment(IMPLICIT_COMMAND_DEPENDENCIES = 0)
-
- INCPREFIX
-
The prefix used to specify an include directory on the C compiler command
line.
This will be appended to the beginning of each directory
in the $CPPPATH and $FORTRANPATH construction variables
when the $_CPPINCFLAGS and $_FORTRANINCFLAGS
variables are automatically generated.
- INCSUFFIX
-
The suffix used to specify an include directory on the C compiler command
line.
This will be appended to the end of each directory
in the $CPPPATH and $FORTRANPATH construction variables
when the $_CPPINCFLAGS and $_FORTRANINCFLAGS
variables are automatically generated.
- INSTALL
-
A function to be called to install a file into a
destination file name.
The default function copies the file into the destination
(and sets the destination file's mode and permission bits
to match the source file's).
The function takes the following arguments:
-
def install(dest, source, env):
-
-
dest
is the path name of the destination file.
source
is the path name of the source file.
env
is the construction environment
(a dictionary of construction values)
in force for this file installation.
- INSTALLSTR
-
The string displayed when a file is
installed into a destination file name.
The default is:
-
Install file: "$SOURCE" as "$TARGET"
-
- INTEL_C_COMPILER_VERSION
-
Set by the "intelc" Tool
to the major version number of the Intel C compiler
selected for use.
- JAR
-
The Java archive tool.
- JARCHDIR
-
The directory to which the Java archive tool should change
(using the
-C
option).
- JARCOM
-
The command line used to call the Java archive tool.
- JARCOMSTR
-
The string displayed when the Java archive tool
is called
If this is not set, then $JARCOM (the command line) is displayed.
-
env = Environment(JARCOMSTR = "JARchiving $SOURCES into $TARGET")
-
- JARFLAGS
-
General options passed to the Java archive tool.
By default this is set to
cf
to create the necessary
jar
file.
- JARSUFFIX
-
The suffix for Java archives:
.jar
by default.
- JAVABOOTCLASSPATH
-
Specifies the list of directories that
will be added to the
&javac; command line
via the -bootclasspath option.
The individual directory names will be
separated by the operating system's path separate character
(: on UNIX/Linux/POSIX,
; on Windows).
- JAVAC
-
The Java compiler.
- JAVACCOM
-
The command line used to compile a directory tree containing
Java source files to
corresponding Java class files.
Any options specified in the $JAVACFLAGS construction variable
are included on this command line.
- JAVACCOMSTR
-
The string displayed when compiling
a directory tree of Java source files to
corresponding Java class files.
If this is not set, then $JAVACCOM (the command line) is displayed.
-
env = Environment(JAVACCOMSTR = "Compiling class files $TARGETS from $SOURCES")
-
- JAVACFLAGS
-
General options that are passed to the Java compiler.
- JAVACLASSDIR
-
The directory in which Java class files may be found.
This is stripped from the beginning of any Java .class
file names supplied to the
JavaH
builder.
- JAVACLASSPATH
-
Specifies the list of directories that
will be searched for Java
.class file.
The directories in this list will be added to the
&javac; and &javah; command lines
via the -classpath option.
The individual directory names will be
separated by the operating system's path separate character
(: on UNIX/Linux/POSIX,
; on Windows).
Note that this currently just adds the specified directory via the -classpath option. &SCons; does not currently search the $JAVACLASSPATH directories for dependency .class files.
- JAVACLASSSUFFIX
-
The suffix for Java class files;
.class
by default.
- JAVAH
-
The Java generator for C header and stub files.
- JAVAHCOM
-
The command line used to generate C header and stub files
from Java classes.
Any options specified in the $JAVAHFLAGS construction variable
are included on this command line.
- JAVAHCOMSTR
-
The string displayed when C header and stub files
are generated from Java classes.
If this is not set, then $JAVAHCOM (the command line) is displayed.
-
env = Environment(JAVAHCOMSTR = "Generating header/stub file(s) $TARGETS from $SOURCES")
-
- JAVAHFLAGS
-
General options passed to the C header and stub file generator
for Java classes.
- JAVASOURCEPATH
-
Specifies the list of directories that
will be searched for input
.java file.
The directories in this list will be added to the
&javac; command line
via the -sourcepath option.
The individual directory names will be
separated by the operating system's path separate character
(: on UNIX/Linux/POSIX,
; on Windows).
Note that this currently just adds the specified directory via the -sourcepath option. &SCons; does not currently search the $JAVASOURCEPATH directories for dependency .java files.
- JAVASUFFIX
-
The suffix for Java files;
.java
by default.
- JAVAVERSION
-
Specifies the Java version being used by the Java() builder.
This is not currently used to select one
version of the Java compiler vs. another.
Instead, you should set this to specify the version of Java
supported by your &javac; compiler.
The default is 1.4.
This is sometimes necessary because Java 1.5 changed the file names that are created for nested anonymous inner classes, which can cause a mismatch with the files that &SCons; expects will be generated by the &javac; compiler. Setting $JAVAVERSION to 1.5 (or 1.6, as appropriate) can make &SCons; realize that a Java 1.5 or 1.6 build is actually up to date.
- LATEX
-
The LaTeX structured formatter and typesetter.
- LATEXCOM
-
The command line used to call the LaTeX structured formatter and typesetter.
- LATEXCOMSTR
-
The string displayed when calling
the LaTeX structured formatter and typesetter.
If this is not set, then $LATEXCOM (the command line) is displayed.
-
env = Environment(LATEXCOMSTR = "Building $TARGET from LaTeX input $SOURCES")
-
- LATEXFLAGS
-
General options passed to the LaTeX structured formatter and typesetter.
- LATEXRETRIES
-
The maximum number of times that LaTeX
will be re-run if the
.log
generated by the $LATEXCOM command
indicates that there are undefined references.
The default is to try to resolve undefined references
by re-running LaTeX up to three times.
- LATEXSUFFIXES
-
The list of suffixes of files that will be scanned
for LaTeX implicit dependencies
(\include or \import files).
The default list is:
-
[".tex", ".ltx", ".latex"]
-
- LDMODULE
-
The linker for building loadable modules.
By default, this is the same as $SHLINK.
- LDMODULECOM
-
The command line for building loadable modules.
On Mac OS X, this uses the $LDMODULE,
$LDMODULEFLAGS and
$FRAMEWORKSFLAGS variables.
On other systems, this is the same as $SHLINK.
- LDMODULECOMSTR
-
The string displayed when building loadable modules.
If this is not set, then $LDMODULECOM (the command line) is displayed.
- LDMODULEFLAGS
-
General user options passed to the linker for building loadable modules.
- LDMODULEPREFIX
-
The prefix used for loadable module file names.
On Mac OS X, this is null;
on other systems, this is
the same as $SHLIBPREFIX.
- LDMODULESUFFIX
-
The suffix used for loadable module file names.
On Mac OS X, this is null;
on other systems, this is
the same as $SHLIBSUFFIX.
- LEX
-
The lexical analyzer generator.
- LEXCOM
-
The command line used to call the lexical analyzer generator
to generate a source file.
- LEXCOMSTR
-
The string displayed when generating a source file
using the lexical analyzer generator.
If this is not set, then $LEXCOM (the command line) is displayed.
-
env = Environment(LEXCOMSTR = "Lex'ing $TARGET from $SOURCES")
-
- LEXFLAGS
-
General options passed to the lexical analyzer generator.
- _LIBDIRFLAGS
-
An automatically-generated construction variable
containing the linker command-line options
for specifying directories to be searched for library.
The value of $_LIBDIRFLAGS is created
by appending $LIBDIRPREFIX and $LIBDIRSUFFIX
to the beginning and end
of each directory in $LIBPATH.
- LIBDIRPREFIX
-
The prefix used to specify a library directory on the linker command line.
This will be appended to the beginning of each directory
in the $LIBPATH construction variable
when the $_LIBDIRFLAGS variable is automatically generated.
- LIBDIRSUFFIX
-
The suffix used to specify a library directory on the linker command line.
This will be appended to the end of each directory
in the $LIBPATH construction variable
when the $_LIBDIRFLAGS variable is automatically generated.
- _LIBFLAGS
-
An automatically-generated construction variable
containing the linker command-line options
for specifying libraries to be linked with the resulting target.
The value of $_LIBFLAGS is created
by appending $LIBLINKPREFIX and $LIBLINKSUFFIX
to the beginning and end
of each filename in $LIBS.
- LIBLINKPREFIX
-
The prefix used to specify a library to link on the linker command line.
This will be appended to the beginning of each library
in the $LIBS construction variable
when the $_LIBFLAGS variable is automatically generated.
- LIBLINKSUFFIX
-
The suffix used to specify a library to link on the linker command line.
This will be appended to the end of each library
in the $LIBS construction variable
when the $_LIBFLAGS variable is automatically generated.
- LIBPATH
-
The list of directories that will be searched for libraries.
The implicit dependency scanner will search these
directories for include files. Don't explicitly put include directory
arguments in $LINKFLAGS or $SHLINKFLAGS
because the result will be non-portable
and the directories will not be searched by the dependency scanner. Note:
directory names in LIBPATH will be looked-up relative to the SConscript
directory when they are used in a command. To force
scons
to look-up a directory relative to the root of the source tree use #:
-
env = Environment(LIBPATH='#/libs')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
libs = Dir('libs') env = Environment(LIBPATH=libs)
-
-
The directory list will be added to command lines
through the automatically-generated
$_LIBDIRFLAGS
construction variable,
which is constructed by
appending the values of the
$LIBDIRPREFIX and $LIBDIRSUFFIX
construction variables
to the beginning and end
of each directory in $LIBPATH.
Any command lines you define that need
the LIBPATH directory list should
include $_LIBDIRFLAGS:
-
env = Environment(LINKCOM="my_linker $_LIBDIRFLAGS $_LIBFLAGS -o $TARGET $SOURCE")
-
- LIBPREFIX
-
The prefix used for (static) library file names.
A default value is set for each platform
(posix, win32, os2, etc.),
but the value is overridden by individual tools
(ar, mslib, sgiar, sunar, tlib, etc.)
to reflect the names of the libraries they create.
- LIBPREFIXES
-
A list of all legal prefixes for library file names.
When searching for library dependencies,
SCons will look for files with these prefixes,
the base library name,
and suffixes in the $LIBSUFFIXES list.
- LIBS
-
A list of one or more libraries
that will be linked with
any executable programs
created by this environment.
The library list will be added to command lines through the automatically-generated $_LIBFLAGS construction variable, which is constructed by appending the values of the $LIBLINKPREFIX and $LIBLINKSUFFIX construction variables to the beginning and end of each filename in $LIBS. Any command lines you define that need the LIBS library list should include $_LIBFLAGS:
-
env = Environment(LINKCOM="my_linker $_LIBDIRFLAGS $_LIBFLAGS -o $TARGET $SOURCE")
-
-
If you add a
File
object to the
$LIBS
list, the name of that file will be added to
$_LIBFLAGS,
and thus the link line, as is, without
$LIBLINKPREFIX
or
$LIBLINKSUFFIX.
For example:
-
env.Append(LIBS=File('/tmp/mylib.so'))
-
-
In all cases, scons will add dependencies from the executable program to
all the libraries in this list.
- LIBSUFFIX
-
The suffix used for (static) library file names.
A default value is set for each platform
(posix, win32, os2, etc.),
but the value is overridden by individual tools
(ar, mslib, sgiar, sunar, tlib, etc.)
to reflect the names of the libraries they create.
- LIBSUFFIXES
-
A list of all legal suffixes for library file names.
When searching for library dependencies,
SCons will look for files with prefixes, in the $LIBPREFIXES list,
the base library name,
and these suffixes.
- LICENSE
-
The abbreviated name of the license under which
this project is released (gpl, lpgl, bsd etc.).
See http://www.opensource.org/licenses/alphabetical
for a list of license names.
- LINESEPARATOR
-
The separator used by the Substfile() and Textfile() builders.
This value is used between sources when constructing the target.
It defaults to the current system line separator.
- LINK
-
The linker.
- LINKCOM
-
The command line used to link object files into an executable.
- LINKCOMSTR
-
The string displayed when object files
are linked into an executable.
If this is not set, then $LINKCOM (the command line) is displayed.
-
env = Environment(LINKCOMSTR = "Linking $TARGET")
-
- LINKFLAGS
-
General user options passed to the linker.
Note that this variable should
not
contain
-l
(or similar) options for linking with the libraries listed in $LIBS,
nor
-L
(or similar) library search path options
that scons generates automatically from $LIBPATH.
See
$_LIBFLAGS
above,
for the variable that expands to library-link options,
and
$_LIBDIRFLAGS
above,
for the variable that expands to library search path options.
- M4
-
The M4 macro preprocessor.
- M4COM
-
The command line used to pass files through the M4 macro preprocessor.
- M4COMSTR
-
The string displayed when
a file is passed through the M4 macro preprocessor.
If this is not set, then $M4COM (the command line) is displayed.
- M4FLAGS
-
General options passed to the M4 macro preprocessor.
- MAKEINDEX
-
The makeindex generator for the TeX formatter and typesetter and the
LaTeX structured formatter and typesetter.
- MAKEINDEXCOM
-
The command line used to call the makeindex generator for the
TeX formatter and typesetter and the LaTeX structured formatter and
typesetter.
- MAKEINDEXCOMSTR
-
The string displayed when calling the makeindex generator for the
TeX formatter and typesetter
and the LaTeX structured formatter and typesetter.
If this is not set, then $MAKEINDEXCOM (the command line) is displayed.
- MAKEINDEXFLAGS
-
General options passed to the makeindex generator for the TeX formatter
and typesetter and the LaTeX structured formatter and typesetter.
- MAXLINELENGTH
-
The maximum number of characters allowed on an external command line.
On Win32 systems,
link lines longer than this many characters
are linked via a temporary file name.
- MIDL
-
The Microsoft IDL compiler.
- MIDLCOM
-
The command line used to pass files to the Microsoft IDL compiler.
- MIDLCOMSTR
-
The string displayed when
the Microsoft IDL copmiler is called.
If this is not set, then $MIDLCOM (the command line) is displayed.
- MIDLFLAGS
-
General options passed to the Microsoft IDL compiler.
- MSSDK_DIR
-
The directory containing the Microsoft SDK
(either Platform SDK or Windows SDK)
to be used for compilation.
- MSSDK_VERSION
-
The version string of the Microsoft SDK
(either Platform SDK or Windows SDK)
to be used for compilation.
Supported versions include
6.1,
6.0A,
6.0,
2003R2
and
2003R1.
- MSVC_BATCH
-
When set to any true value,
specifies that SCons should batch
compilation of object files
when calling the Microsoft Visual C/C++ compiler.
All compilations of source files from the same source directory
that generate target files in a same output directory
and were configured in SCons using the same construction environment
will be built in a single call to the compiler.
Only source files that have changed since their
object files were built will be passed to each compiler invocation
(via the $CHANGED_SOURCES construction variable).
Any compilations where the object (target) file base name
(minus the .obj)
does not match the source file base name
will be compiled separately.
- MSVC_USE_SCRIPT
-
Use a batch script to set up Microsoft Visual Studio compiler
$MSVC_USE_SCRIPT overrides $MSVC_VERSION and $TARGET_ARCH. If set to the name of a Visual Studio .bat file (e.g. vcvars.bat), SCons will run that bat file and extract the relevant variables from the result (typically %INCLUDE%, %LIB%, and %PATH%). Setting MSVC_USE_SCRIPT to None bypasses the Visual Studio autodetection entirely; use this if you are running SCons in a Visual Studio cmd window and importing the shell's environment variables.
- MSVC_VERSION
-
Sets the preferred version of Microsoft Visual C/C++ to use.
If $MSVC_VERSION is not set, SCons will (by default) select the latest version of Visual C/C++ installed on your system. If the specified version isn't installed, tool initialization will fail. This variable must be passed as an argument to the Environment() constructor; setting it later has no effect. Set it to an unexpected value (e.g. "XXX") to see the valid values on your system.
- MSVS
-
When the Microsoft Visual Studio tools are initialized, they set up
this dictionary with the following keys:
VERSION: the version of MSVS being used (can be set via $MSVS_VERSION)
VERSIONS: the available versions of MSVS installed
VCINSTALLDIR: installed directory of Visual C++
VSINSTALLDIR: installed directory of Visual Studio
FRAMEWORKDIR: installed directory of the .NET framework
FRAMEWORKVERSIONS: list of installed versions of the .NET framework, sorted latest to oldest.
FRAMEWORKVERSION: latest installed version of the .NET framework
FRAMEWORKSDKDIR: installed location of the .NET SDK.
PLATFORMSDKDIR: installed location of the Platform SDK.
PLATFORMSDK_MODULES: dictionary of installed Platform SDK modules, where the dictionary keys are keywords for the various modules, and the values are 2-tuples where the first is the release date, and the second is the version number.
If a value isn't set, it wasn't available in the registry.
- MSVS_ARCH
-
Sets the architecture for which the generated project(s) should build.
The default value is x86. amd64 is also supported by &SCons; for some Visual Studio versions. Trying to set $MSVS_ARCH to an architecture that's not supported for a given Visual Studio version will generate an error.
- MSVS_PROJECT_BASE_PATH
-
The string
placed in a generated Microsoft Visual Studio solution file
as the value of the
SccProjectFilePathRelativizedFromConnection0
and
SccProjectFilePathRelativizedFromConnection1
attributes of the
GlobalSection(SourceCodeControl)
section.
There is no default value.
- MSVS_PROJECT_GUID
-
The string
placed in a generated Microsoft Visual Studio project file
as the value of the
ProjectGUID
attribute.
The string is also placed in the
SolutionUniqueID
attribute of the
GlobalSection(SourceCodeControl)
section of the Microsoft Visual Studio solution file.
There is no default value.
- MSVS_SCC_AUX_PATH
-
The path name
placed in a generated Microsoft Visual Studio project file
as the value of the
SccAuxPath
attribute
if the
MSVS_SCC_PROVIDER
construction variable is also set.
There is no default value.
- MSVS_SCC_LOCAL_PATH
-
The path name
placed in a generated Microsoft Visual Studio project file
as the value of the
SccLocalPath
attribute
if the
MSVS_SCC_PROVIDER
construction variable is also set.
The path name is also placed in the
SccLocalPath0
and
SccLocalPath1
attributes of the
GlobalSection(SourceCodeControl)
section of the Microsoft Visual Studio solution file.
There is no default value.
- MSVS_SCC_PROJECT_NAME
-
The project name
placed in a generated Microsoft Visual Studio project file
as the value of the
SccProjectName
attribute.
There is no default value.
- MSVS_SCC_PROVIDER
-
The string
placed in a generated Microsoft Visual Studio project file
as the value of the
SccProvider
attribute.
The string is also placed in the
SccProvider1
attribute of the
GlobalSection(SourceCodeControl)
section of the Microsoft Visual Studio solution file.
There is no default value.
- MSVS_VERSION
-
Sets the preferred version of Microsoft Visual Studio to use.
If $MSVS_VERSION is not set, &SCons; will (by default) select the latest version of Visual Studio installed on your system. So, if you have version 6 and version 7 (MSVS .NET) installed, it will prefer version 7. You can override this by specifying the MSVS_VERSION variable in the Environment initialization, setting it to the appropriate version ('6.0' or '7.0', for example). If the specified version isn't installed, tool initialization will fail.
This is obsolete: use $MSVC_VERSION instead. If $MSVS_VERSION is set and $MSVC_VERSION is not, $MSVC_VERSION will be set automatically to $MSVS_VERSION. If both are set to different values, scons will raise an error.
- MSVSBUILDCOM
-
The build command line placed in
a generated Microsoft Visual Studio project file.
The default is to have Visual Studio invoke SCons with any specified
build targets.
- MSVSCLEANCOM
-
The clean command line placed in
a generated Microsoft Visual Studio project file.
The default is to have Visual Studio invoke SCons with the -c option
to remove any specified targets.
- MSVSENCODING
-
The encoding string placed in
a generated Microsoft Visual Studio project file.
The default is encoding
Windows-1252.
- MSVSPROJECTCOM
-
The action used to generate Microsoft Visual Studio project files.
- MSVSPROJECTSUFFIX
-
The suffix used for Microsoft Visual Studio project (DSP) files.
The default value is
.vcproj
when using Visual Studio version 7.x (.NET)
or later version,
and
.dsp
when using earlier versions of Visual Studio.
- MSVSREBUILDCOM
-
The rebuild command line placed in
a generated Microsoft Visual Studio project file.
The default is to have Visual Studio invoke SCons with any specified
rebuild targets.
- MSVSSCONS
-
The SCons used in generated Microsoft Visual Studio project files.
The default is the version of SCons being
used to generate the project file.
- MSVSSCONSCOM
-
The default SCons command used in generated Microsoft Visual Studio
project files.
- MSVSSCONSCRIPT
-
The sconscript file
(that is,
SConstruct
or
SConscript
file)
that will be invoked by Visual Studio
project files
(through the
$MSVSSCONSCOM
variable).
The default is the same sconscript file
that contains the call to
MSVSProject()
to build the project file.
- MSVSSCONSFLAGS
-
The SCons flags used in generated Microsoft Visual Studio
project files.
- MSVSSOLUTIONCOM
-
The action used to generate Microsoft Visual Studio solution files.
- MSVSSOLUTIONSUFFIX
-
The suffix used for Microsoft Visual Studio solution (DSW) files.
The default value is
.sln
when using Visual Studio version 7.x (.NET),
and
.dsw
when using earlier versions of Visual Studio.
- MWCW_VERSION
-
The version number of the MetroWerks CodeWarrior C compiler
to be used.
- MWCW_VERSIONS
-
A list of installed versions of the MetroWerks CodeWarrior C compiler
on this system.
- NAME
-
Specfies the name of the project to package.
- no_import_lib
-
When set to non-zero,
suppresses creation of a corresponding Windows static import lib by the
SharedLibrary
builder when used with
MinGW, Microsoft Visual Studio or Metrowerks.
This also suppresses creation
of an export (.exp) file
when using Microsoft Visual Studio.
- OBJPREFIX
-
The prefix used for (static) object file names.
- OBJSUFFIX
-
The suffix used for (static) object file names.
- P4
-
The Perforce executable.
- P4COM
-
The command line used to
fetch source files from Perforce.
- P4COMSTR
-
The string displayed when
fetching a source file from Perforce.
If this is not set, then $P4COM (the command line) is displayed.
- P4FLAGS
-
General options that are passed to Perforce.
- PACKAGEROOT
-
Specifies the directory where all files in resulting archive will be
placed if applicable. The default value is "$NAME-$VERSION".
- PACKAGETYPE
-
Selects the package type to build. Currently these are available:
* msi - Microsoft Installer
* rpm - Redhat Package Manger
* ipkg - Itsy Package Management System
* tarbz2 - compressed tar
* targz - compressed tar
* zip - zip file
* src_tarbz2 - compressed tar source
* src_targz - compressed tar source
* src_zip - zip file sourceThis may be overridden with the "package_type" command line option.
- PACKAGEVERSION
-
The version of the package (not the underlying project).
This is currently only used by the rpm packager
and should reflect changes in the packaging,
not the underlying project code itself.
- PCH
-
The Microsoft Visual C++ precompiled header that will be used when compiling
object files. This variable is ignored by tools other than Microsoft Visual C++.
When this variable is
defined SCons will add options to the compiler command line to
cause it to use the precompiled header, and will also set up the
dependencies for the PCH file.
Example:
-
env['PCH'] = 'StdAfx.pch'
-
- PCHCOM
-
The command line used by the
PCH()
builder to generated a precompiled header.
- PCHCOMSTR
-
The string displayed when generating a precompiled header.
If this is not set, then $PCHCOM (the command line) is displayed.
- PCHPDBFLAGS
-
A construction variable that, when expanded,
adds the /yD flag to the command line
only if the $PDB construction variable is set.
- PCHSTOP
-
This variable specifies how much of a source file is precompiled. This
variable is ignored by tools other than Microsoft Visual C++, or when
the PCH variable is not being used. When this variable is define it
must be a string that is the name of the header that
is included at the end of the precompiled portion of the source files, or
the empty string if the "#pragma hrdstop" construct is being used:
-
env['PCHSTOP'] = 'StdAfx.h'
-
- PDB
-
The Microsoft Visual C++ PDB file that will store debugging information for
object files, shared libraries, and programs. This variable is ignored by
tools other than Microsoft Visual C++.
When this variable is
defined SCons will add options to the compiler and linker command line to
cause them to generate external debugging information, and will also set up the
dependencies for the PDB file.
Example:
-
env['PDB'] = 'hello.pdb'
-
-
The Visual C++ compiler switch that SCons uses by default
to generate PDB information is /Z7.
This works correctly with parallel (-j) builds
because it embeds the debug information in the intermediate object files,
as opposed to sharing a single PDB file between multiple object files.
This is also the only way to get debug information
embedded into a static library.
Using the /Zi instead may yield improved
link-time performance,
although parallel builds will no longer work.
You can generate PDB files with the /Zi
switch by overriding the default $CCPDBFLAGS variable;
see the entry for that variable for specific examples.
- PDFCOM
-
A deprecated synonym for $DVIPDFCOM.
- PDFLATEX
-
The &pdflatex; utility.
- PDFLATEXCOM
-
The command line used to call the &pdflatex; utility.
- PDFLATEXCOMSTR
-
The string displayed when calling the &pdflatex; utility.
If this is not set, then $PDFLATEXCOM (the command line) is displayed.
-
env = Environment(PDFLATEX;COMSTR = "Building $TARGET from LaTeX input $SOURCES")
-
- PDFLATEXFLAGS
-
General options passed to the &pdflatex; utility.
- PDFPREFIX
-
The prefix used for PDF file names.
- PDFSUFFIX
-
The suffix used for PDF file names.
- PDFTEX
-
The &pdftex; utility.
- PDFTEXCOM
-
The command line used to call the &pdftex; utility.
- PDFTEXCOMSTR
-
The string displayed when calling the &pdftex; utility.
If this is not set, then $PDFTEXCOM (the command line) is displayed.
-
env = Environment(PDFTEXCOMSTR = "Building $TARGET from TeX input $SOURCES")
-
- PDFTEXFLAGS
-
General options passed to the &pdftex; utility.
- PKGCHK
-
On Solaris systems,
the package-checking program that will
be used (along with $PKGINFO)
to look for installed versions of
the Sun PRO C++ compiler.
The default is
/usr/sbin/pgkchk.
- PKGINFO
-
On Solaris systems,
the package information program that will
be used (along with $PKGCHK)
to look for installed versions of
the Sun PRO C++ compiler.
The default is
pkginfo.
- PLATFORM
-
The name of the platform used to create the Environment. If no platform is
specified when the Environment is created,
scons
autodetects the platform.
-
env = Environment(tools = []) if env['PLATFORM'] == 'cygwin': Tool('mingw')(env) else: Tool('msvc')(env)
-
- PRINT_CMD_LINE_FUNC
-
A Python function used to print the command lines as they are executed
(assuming command printing is not disabled by the
-q
or
-s
options or their equivalents).
The function should take four arguments:
s,
the command being executed (a string),
target,
the target being built (file node, list, or string name(s)),
source,
the source(s) used (file node, list, or string name(s)), and
env,
the environment being used.
The function must do the printing itself. The default implementation, used if this variable is not set or is None, is:
-
def print_cmd_line(s, target, source, env): sys.stdout.write(s + "
")
-
-
Here's an example of a more interesting function:
-
def print_cmd_line(s, target, source, env): sys.stdout.write("Building %s -> %s...
" % (' and '.join([str(x) for x in source]), ' and '.join([str(x) for x in target]))) env=Environment(PRINT_CMD_LINE_FUNC=print_cmd_line) env.Program('foo', 'foo.c')
-
-
This just prints "Building targetname from sourcename..." instead
of the actual commands.
Such a function could also log the actual commands to a log file,
for example.
- PROGPREFIX
-
The prefix used for executable file names.
- PROGSUFFIX
-
The suffix used for executable file names.
- PSCOM
-
The command line used to convert TeX DVI files into a PostScript file.
- PSCOMSTR
-
The string displayed when a TeX DVI file
is converted into a PostScript file.
If this is not set, then $PSCOM (the command line) is displayed.
- PSPREFIX
-
The prefix used for PostScript file names.
- PSSUFFIX
-
The prefix used for PostScript file names.
- QT_AUTOSCAN
-
Turn off scanning for mocable files. Use the Moc Builder to explicitly
specify files to run moc on.
- QT_BINPATH
-
The path where the qt binaries are installed.
The default value is '$QTDIR/bin'.
- QT_CPPPATH
-
The path where the qt header files are installed.
The default value is '$QTDIR/include'.
Note: If you set this variable to None,
the tool won't change the $CPPPATH
construction variable.
- QT_DEBUG
-
Prints lots of debugging information while scanning for moc files.
- QT_LIB
-
Default value is 'qt'. You may want to set this to 'qt-mt'. Note: If you set
this variable to None, the tool won't change the $LIBS variable.
- QT_LIBPATH
-
The path where the qt libraries are installed.
The default value is '$QTDIR/lib'.
Note: If you set this variable to None,
the tool won't change the $LIBPATH
construction variable.
- QT_MOC
-
Default value is '$QT_BINPATH/moc'.
- QT_MOCCXXPREFIX
-
Default value is ''. Prefix for moc output files, when source is a cxx file.
- QT_MOCCXXSUFFIX
-
Default value is '.moc'. Suffix for moc output files, when source is a cxx
file.
- QT_MOCFROMCXXCOM
-
Command to generate a moc file from a cpp file.
- QT_MOCFROMCXXCOMSTR
-
The string displayed when generating a moc file from a cpp file.
If this is not set, then $QT_MOCFROMCXXCOM (the command line) is displayed.
- QT_MOCFROMCXXFLAGS
-
Default value is '-i'. These flags are passed to moc, when moccing a
C++ file.
- QT_MOCFROMHCOM
-
Command to generate a moc file from a header.
- QT_MOCFROMHCOMSTR
-
The string displayed when generating a moc file from a cpp file.
If this is not set, then $QT_MOCFROMHCOM (the command line) is displayed.
- QT_MOCFROMHFLAGS
-
Default value is ''. These flags are passed to moc, when moccing a header
file.
- QT_MOCHPREFIX
-
Default value is 'moc_'. Prefix for moc output files, when source is a header.
- QT_MOCHSUFFIX
-
Default value is '$CXXFILESUFFIX'. Suffix for moc output files, when source is
a header.
- QT_UIC
-
Default value is '$QT_BINPATH/uic'.
- QT_UICCOM
-
Command to generate header files from .ui files.
- QT_UICCOMSTR
-
The string displayed when generating header files from .ui files.
If this is not set, then $QT_UICCOM (the command line) is displayed.
- QT_UICDECLFLAGS
-
Default value is ''. These flags are passed to uic, when creating a a h
file from a .ui file.
- QT_UICDECLPREFIX
-
Default value is ''. Prefix for uic generated header files.
- QT_UICDECLSUFFIX
-
Default value is '.h'. Suffix for uic generated header files.
- QT_UICIMPLFLAGS
-
Default value is ''. These flags are passed to uic, when creating a cxx
file from a .ui file.
- QT_UICIMPLPREFIX
-
Default value is 'uic_'. Prefix for uic generated implementation files.
- QT_UICIMPLSUFFIX
-
Default value is '$CXXFILESUFFIX'. Suffix for uic generated implementation
files.
- QT_UISUFFIX
-
Default value is '.ui'. Suffix of designer input files.
- QTDIR
-
The qt tool tries to take this from os.environ.
It also initializes all QT_*
construction variables listed below.
(Note that all paths are constructed
with python's os.path.join() method,
but are listed here with the '/' separator
for easier reading.)
In addition, the construction environment
variables $CPPPATH,
$LIBPATH and
$LIBS may be modified
and the variables
PROGEMITTER, SHLIBEMITTER and LIBEMITTER
are modified. Because the build-performance is affected when using this tool,
you have to explicitly specify it at Environment creation:
-
Environment(tools=['default','qt'])
-
-
The qt tool supports the following operations:
Automatic moc file generation from header files. You do not have to specify moc files explicitly, the tool does it for you. However, there are a few preconditions to do so: Your header file must have the same filebase as your implementation file and must stay in the same directory. It must have one of the suffixes .h, .hpp, .H, .hxx, .hh. You can turn off automatic moc file generation by setting QT_AUTOSCAN to 0. See also the corresponding builder method Moc()
Automatic moc file generation from cxx files. As stated in the qt documentation, include the moc file at the end of the cxx file. Note that you have to include the file, which is generated by the transformation ${QT_MOCCXXPREFIX}<basename>${QT_MOCCXXSUFFIX}, by default <basename>.moc. A warning is generated after building the moc file, if you do not include the correct file. If you are using VariantDir, you may need to specify duplicate=1. You can turn off automatic moc file generation by setting QT_AUTOSCAN to 0. See also the corresponding Moc() builder method.
Automatic handling of .ui files. The implementation files generated from .ui files are handled much the same as yacc or lex files. Each .ui file given as a source of Program, Library or SharedLibrary will generate three files, the declaration file, the implementation file and a moc file. Because there are also generated headers, you may need to specify duplicate=1 in calls to VariantDir. See also the corresponding Uic() builder method.
- RANLIB
-
The archive indexer.
- RANLIBCOM
-
The command line used to index a static library archive.
- RANLIBCOMSTR
-
The string displayed when a static library archive is indexed.
If this is not set, then $RANLIBCOM (the command line) is displayed.
-
env = Environment(RANLIBCOMSTR = "Indexing $TARGET")
-
- RANLIBFLAGS
-
General options passed to the archive indexer.
- RC
-
The resource compiler used to build
a Microsoft Visual C++ resource file.
- RCCOM
-
The command line used to build
a Microsoft Visual C++ resource file.
- RCCOMSTR
-
The string displayed when invoking the resource compiler
to build a Microsoft Visual C++ resource file.
If this is not set, then $RCCOM (the command line) is displayed.
- RCFLAGS
-
The flags passed to the resource compiler by the RES builder.
- RCINCFLAGS
-
An automatically-generated construction variable
containing the command-line options
for specifying directories to be searched
by the resource compiler.
The value of $RCINCFLAGS is created
by appending $RCINCPREFIX and $RCINCSUFFIX
to the beginning and end
of each directory in $CPPPATH.
- RCINCPREFIX
-
The prefix (flag) used to specify an include directory
on the resource compiler command line.
This will be appended to the beginning of each directory
in the $CPPPATH construction variable
when the $RCINCFLAGS variable is expanded.
- RCINCSUFFIX
-
The suffix used to specify an include directory
on the resource compiler command line.
This will be appended to the end of each directory
in the $CPPPATH construction variable
when the $RCINCFLAGS variable is expanded.
- RCS
-
The RCS executable.
Note that this variable is not actually used
for the command to fetch source files from RCS;
see the
$RCS_CO
construction variable, below.
- RCS_CO
-
The RCS "checkout" executable,
used to fetch source files from RCS.
- RCS_COCOM
-
The command line used to
fetch (checkout) source files from RCS.
- RCS_COCOMSTR
-
The string displayed when fetching
a source file from RCS.
If this is not set, then $RCS_COCOM
(the command line) is displayed.
- RCS_COFLAGS
-
Options that are passed to the $RCS_CO command.
- RDirs
-
A function that converts a string into a list of Dir instances by
searching the repositories.
- REGSVR
-
The program used on Windows systems
to register a newly-built DLL library
whenever the SharedLibrary() builder
is passed a keyword argument of register=1.
- REGSVRCOM
-
The command line used on Windows systems
to register a newly-built DLL library
whenever the SharedLibrary() builder
is passed a keyword argument of register=1.
- REGSVRCOMSTR
-
The string displayed when registering a newly-built DLL file.
If this is not set, then $REGSVRCOM (the command line) is displayed.
- REGSVRFLAGS
-
Flags passed to the DLL registration program
on Windows systems when a newly-built DLL library is registered.
By default,
this includes the /s
that prevents dialog boxes from popping up
and requiring user attention.
- RMIC
-
The Java RMI stub compiler.
- RMICCOM
-
The command line used to compile stub
and skeleton class files
from Java classes that contain RMI implementations.
Any options specified in the $RMICFLAGS construction variable
are included on this command line.
- RMICCOMSTR
-
The string displayed when compiling
stub and skeleton class files
from Java classes that contain RMI implementations.
If this is not set, then $RMICCOM (the command line) is displayed.
-
env = Environment(RMICCOMSTR = "Generating stub/skeleton class files $TARGETS from $SOURCES")
-
- RMICFLAGS
-
General options passed to the Java RMI stub compiler.
- _RPATH
-
An automatically-generated construction variable
containing the rpath flags to be used when linking
a program with shared libraries.
The value of $_RPATH is created
by appending $RPATHPREFIX and $RPATHSUFFIX
to the beginning and end
of each directory in $RPATH.
- RPATH
-
A list of paths to search for shared libraries when running programs.
Currently only used in the GNU (gnulink),
IRIX (sgilink) and Sun (sunlink) linkers.
Ignored on platforms and toolchains that don't support it.
Note that the paths added to RPATH
are not transformed by
scons
in any way: if you want an absolute
path, you must make it absolute yourself.
- RPATHPREFIX
-
The prefix used to specify a directory to be searched for
shared libraries when running programs.
This will be appended to the beginning of each directory
in the $RPATH construction variable
when the $_RPATH variable is automatically generated.
- RPATHSUFFIX
-
The suffix used to specify a directory to be searched for
shared libraries when running programs.
This will be appended to the end of each directory
in the $RPATH construction variable
when the $_RPATH variable is automatically generated.
- RPCGEN
-
The RPC protocol compiler.
- RPCGENCLIENTFLAGS
-
Options passed to the RPC protocol compiler
when generating client side stubs.
These are in addition to any flags specified in the
$RPCGENFLAGS
construction variable.
- RPCGENFLAGS
-
General options passed to the RPC protocol compiler.
- RPCGENHEADERFLAGS
-
Options passed to the RPC protocol compiler
when generating a header file.
These are in addition to any flags specified in the
$RPCGENFLAGS
construction variable.
- RPCGENSERVICEFLAGS
-
Options passed to the RPC protocol compiler
when generating server side stubs.
These are in addition to any flags specified in the
$RPCGENFLAGS
construction variable.
- RPCGENXDRFLAGS
-
Options passed to the RPC protocol compiler
when generating XDR routines.
These are in addition to any flags specified in the
$RPCGENFLAGS
construction variable.
- SCANNERS
-
A list of the available implicit dependency scanners.
New file scanners may be added by
appending to this list,
although the more flexible approach
is to associate scanners
with a specific Builder.
See the sections "Builder Objects"
and "Scanner Objects,"
below, for more information.
- SCCS
-
The SCCS executable.
- SCCSCOM
-
The command line used to
fetch source files from SCCS.
- SCCSCOMSTR
-
The string displayed when fetching
a source file from a CVS repository.
If this is not set, then $SCCSCOM
(the command line) is displayed.
- SCCSFLAGS
-
General options that are passed to SCCS.
- SCCSGETFLAGS
-
Options that are passed specifically to the SCCS "get" subcommand.
This can be set, for example, to
-e
to check out editable files from SCCS.
- SCONS_HOME
-
The (optional) path to the SCons library directory,
initialized from the external environment.
If set, this is used to construct a shorter and more
efficient search path in the
$MSVSSCONS
command line executed
from Microsoft Visual Studio project files.
- SHCC
-
The C compiler used for generating shared-library objects.
- SHCCCOM
-
The command line used to compile a C source file
to a shared-library object file.
Any options specified in the $SHCFLAGS,
$SHCCFLAGS and
$CPPFLAGS construction variables
are included on this command line.
- SHCCCOMSTR
-
The string displayed when a C source file
is compiled to a shared object file.
If this is not set, then $SHCCCOM (the command line) is displayed.
-
env = Environment(SHCCCOMSTR = "Compiling shared object $TARGET")
-
- SHCCFLAGS
-
Options that are passed to the C and C++ compilers
to generate shared-library objects.
- SHCFLAGS
-
Options that are passed to the C compiler (only; not C++)
to generate shared-library objects.
- SHCXX
-
The C++ compiler used for generating shared-library objects.
- SHCXXCOM
-
The command line used to compile a C++ source file
to a shared-library object file.
Any options specified in the $SHCXXFLAGS and
$CPPFLAGS construction variables
are included on this command line.
- SHCXXCOMSTR
-
The string displayed when a C++ source file
is compiled to a shared object file.
If this is not set, then $SHCXXCOM (the command line) is displayed.
-
env = Environment(SHCXXCOMSTR = "Compiling shared object $TARGET")
-
- SHCXXFLAGS
-
Options that are passed to the C++ compiler
to generate shared-library objects.
- SHELL
-
A string naming the shell program that will be passed to the
$SPAWN
function.
See the
$SPAWN
construction variable for more information.
- SHF77
-
The Fortran 77 compiler used for generating shared-library objects.
You should normally set the $SHFORTRAN variable,
which specifies the default Fortran compiler
for all Fortran versions.
You only need to set $SHF77 if you need to use a specific compiler
or compiler version for Fortran 77 files.
- SHF77COM
-
The command line used to compile a Fortran 77 source file
to a shared-library object file.
You only need to set $SHF77COM if you need to use a specific
command line for Fortran 77 files.
You should normally set the $SHFORTRANCOM variable,
which specifies the default command line
for all Fortran versions.
- SHF77COMSTR
-
The string displayed when a Fortran 77 source file
is compiled to a shared-library object file.
If this is not set, then $SHF77COM or $SHFORTRANCOM
(the command line) is displayed.
- SHF77FLAGS
-
Options that are passed to the Fortran 77 compiler
to generated shared-library objects.
You only need to set $SHF77FLAGS if you need to define specific
user options for Fortran 77 files.
You should normally set the $SHFORTRANFLAGS variable,
which specifies the user-specified options
passed to the default Fortran compiler
for all Fortran versions.
- SHF77PPCOM
-
The command line used to compile a Fortran 77 source file to a
shared-library object file
after first running the file through the C preprocessor.
Any options specified in the $SHF77FLAGS and $CPPFLAGS construction variables
are included on this command line.
You only need to set $SHF77PPCOM if you need to use a specific
C-preprocessor command line for Fortran 77 files.
You should normally set the $SHFORTRANPPCOM variable,
which specifies the default C-preprocessor command line
for all Fortran versions.
- SHF77PPCOMSTR
-
The string displayed when a Fortran 77 source file
is compiled to a shared-library object file
after first running the file through the C preprocessor.
If this is not set, then $SHF77PPCOM or $SHFORTRANPPCOM
(the command line) is displayed.
- SHF90
-
The Fortran 90 compiler used for generating shared-library objects.
You should normally set the $SHFORTRAN variable,
which specifies the default Fortran compiler
for all Fortran versions.
You only need to set $SHF90 if you need to use a specific compiler
or compiler version for Fortran 90 files.
- SHF90COM
-
The command line used to compile a Fortran 90 source file
to a shared-library object file.
You only need to set $SHF90COM if you need to use a specific
command line for Fortran 90 files.
You should normally set the $SHFORTRANCOM variable,
which specifies the default command line
for all Fortran versions.
- SHF90COMSTR
-
The string displayed when a Fortran 90 source file
is compiled to a shared-library object file.
If this is not set, then $SHF90COM or $SHFORTRANCOM
(the command line) is displayed.
- SHF90FLAGS
-
Options that are passed to the Fortran 90 compiler
to generated shared-library objects.
You only need to set $SHF90FLAGS if you need to define specific
user options for Fortran 90 files.
You should normally set the $SHFORTRANFLAGS variable,
which specifies the user-specified options
passed to the default Fortran compiler
for all Fortran versions.
- SHF90PPCOM
-
The command line used to compile a Fortran 90 source file to a
shared-library object file
after first running the file through the C preprocessor.
Any options specified in the $SHF90FLAGS and $CPPFLAGS construction variables
are included on this command line.
You only need to set $SHF90PPCOM if you need to use a specific
C-preprocessor command line for Fortran 90 files.
You should normally set the $SHFORTRANPPCOM variable,
which specifies the default C-preprocessor command line
for all Fortran versions.
- SHF90PPCOMSTR
-
The string displayed when a Fortran 90 source file
is compiled to a shared-library object file
after first running the file through the C preprocessor.
If this is not set, then $SHF90PPCOM or $SHFORTRANPPCOM
(the command line) is displayed.
- SHF95
-
The Fortran 95 compiler used for generating shared-library objects.
You should normally set the $SHFORTRAN variable,
which specifies the default Fortran compiler
for all Fortran versions.
You only need to set $SHF95 if you need to use a specific compiler
or compiler version for Fortran 95 files.
- SHF95COM
-
The command line used to compile a Fortran 95 source file
to a shared-library object file.
You only need to set $SHF95COM if you need to use a specific
command line for Fortran 95 files.
You should normally set the $SHFORTRANCOM variable,
which specifies the default command line
for all Fortran versions.
- SHF95COMSTR
-
The string displayed when a Fortran 95 source file
is compiled to a shared-library object file.
If this is not set, then $SHF95COM or $SHFORTRANCOM
(the command line) is displayed.
- SHF95FLAGS
-
Options that are passed to the Fortran 95 compiler
to generated shared-library objects.
You only need to set $SHF95FLAGS if you need to define specific
user options for Fortran 95 files.
You should normally set the $SHFORTRANFLAGS variable,
which specifies the user-specified options
passed to the default Fortran compiler
for all Fortran versions.
- SHF95PPCOM
-
The command line used to compile a Fortran 95 source file to a
shared-library object file
after first running the file through the C preprocessor.
Any options specified in the $SHF95FLAGS and $CPPFLAGS construction variables
are included on this command line.
You only need to set $SHF95PPCOM if you need to use a specific
C-preprocessor command line for Fortran 95 files.
You should normally set the $SHFORTRANPPCOM variable,
which specifies the default C-preprocessor command line
for all Fortran versions.
- SHF95PPCOMSTR
-
The string displayed when a Fortran 95 source file
is compiled to a shared-library object file
after first running the file through the C preprocessor.
If this is not set, then $SHF95PPCOM or $SHFORTRANPPCOM
(the command line) is displayed.
- SHFORTRAN
-
The default Fortran compiler used for generating shared-library objects.
- SHFORTRANCOM
-
The command line used to compile a Fortran source file
to a shared-library object file.
- SHFORTRANCOMSTR
-
The string displayed when a Fortran source file
is compiled to a shared-library object file.
If this is not set, then $SHFORTRANCOM
(the command line) is displayed.
- SHFORTRANFLAGS
-
Options that are passed to the Fortran compiler
to generate shared-library objects.
- SHFORTRANPPCOM
-
The command line used to compile a Fortran source file to a
shared-library object file
after first running the file through the C preprocessor.
Any options specified
in the $SHFORTRANFLAGS and
$CPPFLAGS construction variables
are included on this command line.
- SHFORTRANPPCOMSTR
-
The string displayed when a Fortran source file
is compiled to a shared-library object file
after first running the file through the C preprocessor.
If this is not set, then $SHFORTRANPPCOM
(the command line) is displayed.
- SHLIBPREFIX
-
The prefix used for shared library file names.
- SHLIBSUFFIX
-
The suffix used for shared library file names.
- SHLINK
-
The linker for programs that use shared libraries.
- SHLINKCOM
-
The command line used to link programs using shared libraries.
- SHLINKCOMSTR
-
The string displayed when programs using shared libraries are linked.
If this is not set, then $SHLINKCOM (the command line) is displayed.
-
env = Environment(SHLINKCOMSTR = "Linking shared $TARGET")
-
- SHLINKFLAGS
-
General user options passed to the linker for programs using shared libraries.
Note that this variable should
not
contain
-l
(or similar) options for linking with the libraries listed in $LIBS,
nor
-L
(or similar) include search path options
that scons generates automatically from $LIBPATH.
See
$_LIBFLAGS
above,
for the variable that expands to library-link options,
and
$_LIBDIRFLAGS
above,
for the variable that expands to library search path options.
- SHOBJPREFIX
-
The prefix used for shared object file names.
- SHOBJSUFFIX
-
The suffix used for shared object file names.
- SOURCE
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- SOURCE_URL
-
The URL
(web address)
of the location from which the project was retrieved.
This is used to fill in the
Source:
field in the controlling information for Ipkg and RPM packages.
- SOURCES
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- SPAWN
-
A command interpreter function that will be called to execute command line
strings. The function must expect the following arguments:
-
def spawn(shell, escape, cmd, args, env):
-
-
sh
is a string naming the shell program to use.
escape
is a function that can be called to escape shell special characters in
the command line.
cmd
is the path to the command to be executed.
args
is the arguments to the command.
env
is a dictionary of the environment variables
in which the command should be executed.
- SUBST_DICT
-
The dictionary used by the Substfile() or Textfile() builders
for substitution values.
It can be anything acceptable to the dict() constructor,
so in addition to a dictionary,
lists of tuples are also acceptable.
- SUBSTFILEPREFIX
-
The prefix used for Substfile() file names,
the null string by default.
- SUBSTFILESUFFIX
-
The suffix used for Substfile() file names,
the null string by default.
- SUMMARY
-
A short summary of what the project is about.
This is used to fill in the
Summary:
field in the controlling information for Ipkg and RPM packages,
and as the
Description:
field in MSI packages.
- SWIG
-
The scripting language wrapper and interface generator.
- SWIGCFILESUFFIX
-
The suffix that will be used for intermediate C
source files generated by
the scripting language wrapper and interface generator.
The default value is
_wrap$CFILESUFFIX.
By default, this value is used whenever the
-c++
option is
not
specified as part of the
$SWIGFLAGS
construction variable.
- SWIGCOM
-
The command line used to call
the scripting language wrapper and interface generator.
- SWIGCOMSTR
-
The string displayed when calling
the scripting language wrapper and interface generator.
If this is not set, then $SWIGCOM (the command line) is displayed.
- SWIGCXXFILESUFFIX
-
The suffix that will be used for intermediate C++
source files generated by
the scripting language wrapper and interface generator.
The default value is
_wrap$CFILESUFFIX.
By default, this value is used whenever the
-c++
option is specified as part of the
$SWIGFLAGS
construction variable.
- SWIGDIRECTORSUFFIX
-
The suffix that will be used for intermediate C++ header
files generated by the scripting language wrapper and interface generator.
These are only generated for C++ code when the SWIG 'directors' feature is
turned on.
The default value is
_wrap.h.
- SWIGFLAGS
-
General options passed to
the scripting language wrapper and interface generator.
This is where you should set
-python,
-perl5,
-tcl,
or whatever other options you want to specify to SWIG.
If you set the
-c++
option in this variable,
scons
will, by default,
generate a C++ intermediate source file
with the extension that is specified as the
$CXXFILESUFFIX
variable.
- _SWIGINCFLAGS
-
An automatically-generated construction variable
containing the SWIG command-line options
for specifying directories to be searched for included files.
The value of $_SWIGINCFLAGS is created
by appending $SWIGINCPREFIX and $SWIGINCSUFFIX
to the beginning and end
of each directory in $SWIGPATH.
- SWIGINCPREFIX
-
The prefix used to specify an include directory on the SWIG command line.
This will be appended to the beginning of each directory
in the $SWIGPATH construction variable
when the $_SWIGINCFLAGS variable is automatically generated.
- SWIGINCSUFFIX
-
The suffix used to specify an include directory on the SWIG command line.
This will be appended to the end of each directory
in the $SWIGPATH construction variable
when the $_SWIGINCFLAGS variable is automatically generated.
- SWIGOUTDIR
-
Specifies the output directory in which
the scripting language wrapper and interface generator
should place generated language-specific files.
This will be used by SCons to identify
the files that will be generated by the &swig; call,
and translated into the
swig -outdir option on the command line.
- SWIGPATH
-
The list of directories that the scripting language wrapper
and interface generate will search for included files.
The SWIG implicit dependency scanner will search these
directories for include files.
The default is to use the same path
specified as $CPPPATH.
Don't explicitly put include directory arguments in SWIGFLAGS; the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in SWIGPATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to look-up a directory relative to the root of the source tree use #:
-
env = Environment(SWIGPATH='#/include')
-
-
The directory look-up can also be forced using the
Dir()
function:
-
include = Dir('include') env = Environment(SWIGPATH=include)
-
-
The directory list will be added to command lines
through the automatically-generated
$_SWIGINCFLAGS
construction variable,
which is constructed by
appending the values of the
$SWIGINCPREFIX and $SWIGINCSUFFIX
construction variables
to the beginning and end
of each directory in $SWIGPATH.
Any command lines you define that need
the SWIGPATH directory list should
include $_SWIGINCFLAGS:
-
env = Environment(SWIGCOM="my_swig -o $TARGET $_SWIGINCFLAGS $SORUCES")
-
- SWIGVERSION
-
The version number of the SWIG tool.
- TAR
-
The tar archiver.
- TARCOM
-
The command line used to call the tar archiver.
- TARCOMSTR
-
The string displayed when archiving files
using the tar archiver.
If this is not set, then $TARCOM (the command line) is displayed.
-
env = Environment(TARCOMSTR = "Archiving $TARGET")
-
- TARFLAGS
-
General options passed to the tar archiver.
- TARGET
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- TARGET_ARCH
-
Sets the target architecture for Visual Studio compiler (i.e. the arch
of the binaries generated by the compiler). If not set, default to
$HOST_ARCH, or, if that is unset, to the architecture of the
running machine's OS (note that the python build or architecture has no
effect).
This variable must be passed as an argument to the Environment()
constructor; setting it later has no effect.
This is currently only used on Windows, but in the future it will be
used on other OSes as well.
Valid values for Windows are x86, i386 (for 32 bits); amd64, emt64, x86_64 (for 64 bits); and ia64 (Itanium). For example, if you want to compile 64-bit binaries, you would set TARGET_ARCH='x86_64' in your SCons environment.
- TARGET_OS
-
The name of the target operating system for the compiled objects
created by this Environment.
This defaults to the value of HOST_OS, and the user can override it.
Currently only set for Win32.
- TARGETS
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- TARSUFFIX
-
The suffix used for tar file names.
- TEMPFILEPREFIX
-
The prefix for a temporary file used
to execute lines longer than $MAXLINELENGTH.
The default is '@'.
This may be set for toolchains that use other values,
such as '-@' for the diab compiler
or '-via' for ARM toolchain.
- TEX
-
The TeX formatter and typesetter.
- TEXCOM
-
The command line used to call the TeX formatter and typesetter.
- TEXCOMSTR
-
The string displayed when calling
the TeX formatter and typesetter.
If this is not set, then $TEXCOM (the command line) is displayed.
-
env = Environment(TEXCOMSTR = "Building $TARGET from TeX input $SOURCES")
-
- TEXFLAGS
-
General options passed to the TeX formatter and typesetter.
- TEXINPUTS
-
List of directories that the LaTeX program will search
for include directories.
The LaTeX implicit dependency scanner will search these
directories for \include and \import files.
- TEXTFILEPREFIX
-
The prefix used for Textfile() file names,
the null string by default.
- TEXTFILESUFFIX
-
The suffix used for Textfile() file names;
.txt by default.
- TOOLS
-
A list of the names of the Tool specifications
that are part of this construction environment.
- UNCHANGED_SOURCES
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- UNCHANGED_TARGETS
-
A reserved variable name
that may not be set or used in a construction environment.
(See "Variable Substitution," below.)
- VENDOR
-
The person or organization who supply the packaged software.
This is used to fill in the
Vendor:
field in the controlling information for RPM packages,
and the
Manufacturer:
field in the controlling information for MSI packages.
- VERSION
-
The version of the project, specified as a string.
- WIN32_INSERT_DEF
-
A deprecated synonym for $WINDOWS_INSERT_DEF.
- WIN32DEFPREFIX
-
A deprecated synonym for $WINDOWSDEFPREFIX.
- WIN32DEFSUFFIX
-
A deprecated synonym for $WINDOWSDEFSUFFIX.
- WIN32EXPPREFIX
-
A deprecated synonym for $WINDOWSEXPSUFFIX.
- WIN32EXPSUFFIX
-
A deprecated synonym for $WINDOWSEXPSUFFIX.
- WINDOWS_INSERT_DEF
-
When this is set to true,
a library build of a Windows shared library
(.dllfile)
will also build a corresponding .def file
at the same time,
if a .def file
is not already listed as a build target.
The default is 0 (do not build a .def file).
- WINDOWS_INSERT_MANIFEST
-
When this is set to true,
scons
will be aware of the
.manifest
files generated by Microsoft Visua C/C++ 8.
- WINDOWSDEFPREFIX
-
The prefix used for Windows .deffile names.
- WINDOWSDEFSUFFIX
-
The suffix used for Windows .def file names.
- WINDOWSEXPPREFIX
-
The prefix used for Windows .exp file names.
- WINDOWSEXPSUFFIX
-
The suffix used for Windows .exp file names.
- WINDOWSPROGMANIFESTPREFIX
-
The prefix used for executable program .manifest files
generated by Microsoft Visual C/C++.
- WINDOWSPROGMANIFESTSUFFIX
-
The suffix used for executable program .manifest files
generated by Microsoft Visual C/C++.
- WINDOWSSHLIBMANIFESTPREFIX
-
The prefix used for shared library .manifest files
generated by Microsoft Visual C/C++.
- WINDOWSSHLIBMANIFESTSUFFIX
-
The suffix used for shared library .manifest files
generated by Microsoft Visual C/C++.
- X_IPK_DEPENDS
-
This is used to fill in the
Depends:
field in the controlling information for Ipkg packages.
- X_IPK_DESCRIPTION
- This is used to fill in the Description: field in the controlling information for Ipkg packages. The default value is $SUMMARY\\$SUMMARY
- X_IPK_MAINTAINER
-
This is used to fill in the
Maintainer:
field in the controlling information for Ipkg packages.
- X_IPK_PRIORITY
-
This is used to fill in the
Priority:
field in the controlling information for Ipkg packages.
- X_IPK_SECTION
-
This is used to fill in the
Section:
field in the controlling information for Ipkg packages.
- X_MSI_LANGUAGE
-
This is used to fill in the
Language:
attribute in the controlling information for MSI packages.
- X_MSI_LICENSE_TEXT
-
The text of the software license in RTF format.
Carriage return characters will be
replaced with the RTF equivalent \
ar. - X_MSI_UPGRADE_CODE
-
TODO
- X_RPM_AUTOREQPROV
-
This is used to fill in the
AutoReqProv:
field in the RPM
.spec file.
- X_RPM_BUILD
-
internal, but overridable
- X_RPM_BUILDREQUIRES
-
This is used to fill in the
BuildRequires:
field in the RPM
.spec file.
- X_RPM_BUILDROOT
-
internal, but overridable
- X_RPM_CLEAN
-
internal, but overridable
- X_RPM_CONFLICTS
-
This is used to fill in the
Conflicts:
field in the RPM
.spec file.
- X_RPM_DEFATTR
-
This value is used as the default attributes
for the files in the RPM package.
The default value is
(-,root,root).
- X_RPM_DISTRIBUTION
-
This is used to fill in the
Distribution:
field in the RPM
.spec file.
- X_RPM_EPOCH
-
This is used to fill in the
Epoch:
field in the controlling information for RPM packages.
- X_RPM_EXCLUDEARCH
-
This is used to fill in the
ExcludeArch:
field in the RPM
.spec file.
- X_RPM_EXLUSIVEARCH
-
This is used to fill in the
ExclusiveArch:
field in the RPM
.spec file.
- X_RPM_GROUP
-
This is used to fill in the
Group:
field in the RPM
.spec file.
- X_RPM_GROUP_lang
-
This is used to fill in the
Group(lang):
field in the RPM
.spec file.
Note that
lang
is not literal
and should be replaced by
the appropriate language code.
- X_RPM_ICON
-
This is used to fill in the
Icon:
field in the RPM
.spec file.
- X_RPM_INSTALL
-
internal, but overridable
- X_RPM_PACKAGER
-
This is used to fill in the
Packager:
field in the RPM
.spec file.
- X_RPM_POSTINSTALL
-
This is used to fill in the
%post:
section in the RPM
.spec file.
- X_RPM_POSTUNINSTALL
-
This is used to fill in the
%postun:
section in the RPM
.spec file.
- X_RPM_PREFIX
-
This is used to fill in the
Prefix:
field in the RPM
.spec file.
- X_RPM_PREINSTALL
-
This is used to fill in the
%pre:
section in the RPM
.spec file.
- X_RPM_PREP
-
internal, but overridable
- X_RPM_PREUNINSTALL
-
This is used to fill in the
%preun:
section in the RPM
.spec file.
- X_RPM_PROVIDES
-
This is used to fill in the
Provides:
field in the RPM
.spec file.
- X_RPM_REQUIRES
-
This is used to fill in the
Requires:
field in the RPM
.spec file.
- X_RPM_SERIAL
-
This is used to fill in the
Serial:
field in the RPM
.spec file.
- X_RPM_URL
-
This is used to fill in the
Url:
field in the RPM
.spec file.
- YACC
-
The parser generator.
- YACCCOM
-
The command line used to call the parser generator
to generate a source file.
- YACCCOMSTR
-
The string displayed when generating a source file
using the parser generator.
If this is not set, then $YACCCOM (the command line) is displayed.
-
env = Environment(YACCCOMSTR = "Yacc'ing $TARGET from $SOURCES")
-
- YACCFLAGS
-
General options passed to the parser generator.
If $YACCFLAGS contains a -d option,
SCons assumes that the call will also create a .h file
(if the yacc source file ends in a .y suffix)
or a .hpp file
(if the yacc source file ends in a .yy suffix)
- YACCHFILESUFFIX
-
The suffix of the C
header file generated by the parser generator
when the
-d
option is used.
Note that setting this variable does not cause
the parser generator to generate a header
file with the specified suffix,
it exists to allow you to specify
what suffix the parser generator will use of its own accord.
The default value is
.h.
- YACCHXXFILESUFFIX
-
The suffix of the C++
header file generated by the parser generator
when the
-d
option is used.
Note that setting this variable does not cause
the parser generator to generate a header
file with the specified suffix,
it exists to allow you to specify
what suffix the parser generator will use of its own accord.
The default value is
.hpp,
except on Mac OS X,
where the default is
${TARGET.suffix}.h.
because the default &bison; parser generator just
appends .h
to the name of the generated C++ file.
- YACCVCGFILESUFFIX
-
The suffix of the file
containing the VCG grammar automaton definition
when the
--graph=
option is used.
Note that setting this variable does not cause
the parser generator to generate a VCG
file with the specified suffix,
it exists to allow you to specify
what suffix the parser generator will use of its own accord.
The default value is
.vcg.
- ZIP
-
The zip compression and file packaging utility.
- ZIPCOM
-
The command line used to call the zip utility,
or the internal Python function used to create a
zip archive.
- ZIPCOMPRESSION
-
The
compression
flag
from the Python
zipfile
module used by the internal Python function
to control whether the zip archive
is compressed or not.
The default value is
zipfile.ZIP_DEFLATED,
which creates a compressed zip archive.
This value has no effect if the
zipfile
module is unavailable.
- ZIPCOMSTR
-
The string displayed when archiving files
using the zip utility.
If this is not set, then $ZIPCOM
(the command line or internal Python function) is displayed.
-
env = Environment(ZIPCOMSTR = "Zipping $TARGET")
-
- ZIPFLAGS
-
General options passed to the zip utility.
- ZIPSUFFIX
-
The suffix used for zip file names.
Construction variables can be retrieved and set using the Dictionary method of the construction environment:
-
dict = env.Dictionary() dict["CC"] = "cc"
or using the [] operator:
-
env["CC"] = "cc"
Construction variables can also be passed to the construction environment constructor:
-
env = Environment(CC="cc")
or when copying a construction environment using the Clone method:
-
env2 = env.Clone(CC="cl.exe")
Configure Contexts
scons supports configure contexts, an integrated mechanism similar to the various AC_CHECK macros in GNU autoconf for testing for the existence of C header files, libraries, etc. In contrast to autoconf, scons does not maintain an explicit cache of the tested values, but uses its normal dependency tracking to keep the checked values up to date. However, users may override this behaviour with the --config command line option.
The following methods can be used to perform checks:
- Configure(env, [custom_tests, conf_dir, log_file, config_h, clean, help])
- env.Configure([custom_tests, conf_dir, log_file, config_h, clean, help])
-
This creates a configure context, which can be used to perform checks.
env
specifies the environment for building the tests.
This environment may be modified when performing checks.
custom_tests
is a dictionary containing custom tests.
See also the section about custom tests below.
By default, no custom tests are added to the configure context.
conf_dir
specifies a directory where the test cases are built.
Note that this directory is not used for building
normal targets.
The default value is the directory
#/.sconf_temp.
log_file
specifies a file which collects the output from commands
that are executed to check for the existence of header files, libraries, etc.
The default is the file #/config.log.
If you are using the
VariantDir()
method,
you may want to specify a subdirectory under your variant directory.
config_h
specifies a C header file where the results of tests
will be written, e.g. #define HAVE_STDIO_H, #define HAVE_LIBM, etc.
The default is to not write a
config.h
file.
You can specify the same
config.h
file in multiple calls to Configure,
in which case
scons
will concatenate all results in the specified file.
Note that SCons
uses its normal dependency checking
to decide if it's necessary to rebuild
the specified
config_h
file.
This means that the file is not necessarily re-built each
time scons is run,
but is only rebuilt if its contents will have changed
and some target that depends on the
config_h
file is being built.
The optional clean and help arguments can be used to suppress execution of the configuration tests when the -c/--clean or -H/-h/--help options are used, respectively. The default behavior is always to execute configure context tests, since the results of the tests may affect the list of targets to be cleaned or the help text. If the configure tests do not affect these, then you may add the clean=False or help=False arguments (or both) to avoid unnecessary test execution.
A created Configure instance has the following associated methods:
- SConf.Finish(context)
- sconf.Finish()
-
This method should be called after configuration is done.
It returns the environment as modified
by the configuration checks performed.
After this method is called, no further checks can be performed
with this configuration context.
However, you can create a new
Configure
context to perform additional checks.
Only one context should be active at a time.
The following Checks are predefined. (This list will likely grow larger as time goes by and developers contribute new useful tests.)
- SConf.CheckHeader(context, header, [include_quotes, language])
- sconf.CheckHeader(header, [include_quotes, language])
-
Checks if
header
is usable in the specified language.
header
may be a list,
in which case the last item in the list
is the header file to be checked,
and the previous list items are
header files whose
#include
lines should precede the
header line being checked for.
The optional argument
include_quotes
must be
a two character string, where the first character denotes the opening
quote and the second character denotes the closing quote.
By default, both characters are " (double quote).
The optional argument
language
should be either
C
or
C++
and selects the compiler to be used for the check.
Returns 1 on success and 0 on failure.
- SConf.CheckCHeader(context, header, [include_quotes])
- sconf.CheckCHeader(header, [include_quotes])
-
This is a wrapper around
SConf.CheckHeader
which checks if
header
is usable in the C language.
header
may be a list,
in which case the last item in the list
is the header file to be checked,
and the previous list items are
header files whose
#include
lines should precede the
header line being checked for.
The optional argument
include_quotes
must be
a two character string, where the first character denotes the opening
quote and the second character denotes the closing quote (both default
to ").
Returns 1 on success and 0 on failure.
- SConf.CheckCXXHeader(context, header, [include_quotes])
- sconf.CheckCXXHeader(header, [include_quotes])
-
This is a wrapper around
SConf.CheckHeader
which checks if
header
is usable in the C++ language.
header
may be a list,
in which case the last item in the list
is the header file to be checked,
and the previous list items are
header files whose
#include
lines should precede the
header line being checked for.
The optional argument
include_quotes
must be
a two character string, where the first character denotes the opening
quote and the second character denotes the closing quote (both default
to ").
Returns 1 on success and 0 on failure.
- SConf.CheckFunc(context,, function_name, [header, language])
- sconf.CheckFunc(function_name, [header, language])
-
Checks if the specified
C or C++ function is available.
function_name
is the name of the function to check for.
The optional
header
argument is a string
that will be
placed at the top
of the test file
that will be compiled
to check if the function exists;
the default is:
-
#ifdef __cplusplus extern "C" #endif char function_name();
-
- SConf.CheckLib(context, [library, symbol, header, language, autoadd=1])
- sconf.CheckLib([library, symbol, header, language, autoadd=1])
-
Checks if
library
provides
symbol.
If the value of
autoadd
is 1 and the library provides the specified
symbol,
appends the library to the LIBS construction environment variable.
library
may also be None (the default),
in which case
symbol
is checked with the current LIBS variable,
or a list of library names,
in which case each library in the list
will be checked for
symbol.
If
symbol
is not set or is
None,
then
SConf.CheckLib()
just checks if
you can link against the specified
library.
The optional
language
argument should be
C
or
C++
and selects the compiler to be used for the check;
the default is "C".
The default value for
autoadd
is 1.
This method returns 1 on success and 0 on error.
- SConf.CheckLibWithHeader(context, library, header, language, [call, autoadd])
- sconf.CheckLibWithHeader(library, header, language, [call, autoadd])
-
In contrast to the SConf.CheckLib call, this call provides a more sophisticated way to check against libraries. Again, library specifies the library or a list of libraries to check. header specifies a header to check for. header may be a list, in which case the last item in the list is the header file to be checked, and the previous list items are header files whose #include lines should precede the header line being checked for. language may be one of 'C','c','CXX','cxx','C++' and 'c++'. call can be any valid expression (with a trailing ';'). If call is not set, the default simply checks that you can link against the specified library. autoadd specifies whether to add the library to the environment (only if the check succeeds). This method returns 1 on success and 0 on error.
- SConf.CheckType(context, type_name, [includes, language])
- sconf.CheckType(type_name, [includes, language])
-
Checks for the existence of a type defined by
typedef.
type_name
specifies the typedef name to check for.
includes
is a string containing one or more
#include
lines that will be inserted into the program
that will be run to test for the existence of the type.
The optional
language
argument should be
C
or
C++
and selects the compiler to be used for the check;
the default is "C".
Example:
-
sconf.CheckType('foo_type', '#include "my_types.h"', 'C++')
-
- Configure.CheckCC(self)
-
Checks whether the C compiler (as defined by the CC construction variable) works
by trying to compile a small source file.
By default, SCons only detects if there is a program with the correct name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for C source file, so it can be used to detect if a particular compiler flag works or not.
- Configure.CheckCXX(self)
-
Checks whether the C++ compiler (as defined by the CXX construction variable)
works by trying to compile a small source file. By default, SCons only detects
if there is a program with the correct name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for CXX source files, so it can be used to detect if a particular compiler flag works or not.
- Configure.CheckSHCC(self)
-
Checks whether the C compiler (as defined by the SHCC construction variable) works
by trying to compile a small source file. By default, SCons only detects if
there is a program with the correct name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for C source file, so it can be used to detect if a particular compiler flag works or not. This does not check whether the object code can be used to build a shared library, only that the compilation (not link) succeeds.
- Configure.CheckSHCXX(self)
-
Checks whether the C++ compiler (as defined by the SHCXX construction variable)
works by trying to compile a small source file. By default, SCons only detects
if there is a program with the correct name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for CXX source files, so it can be used to detect if a particular compiler flag works or not. This does not check whether the object code can be used to build a shared library, only that the compilation (not link) succeeds.
Example of a typical Configure usage:
-
env = Environment() conf = Configure( env ) if not conf.CheckCHeader( 'math.h' ): print 'We really need math.h!' Exit(1) if conf.CheckLibWithHeader( 'qt', 'qapp.h', 'c++', 'QApplication qapp(0,0);' ): # do stuff for qt - usage, e.g. conf.env.Append( CPPFLAGS = '-DWITH_QT' ) env = conf.Finish()
-
- SConf.CheckTypeSize(context, type_name, [header, language, expect])
- sconf.CheckTypeSize(type_name, [header, language, expect])
-
Checks for the size of a type defined by
typedef.
type_name
specifies the typedef name to check for.
The optional
header
argument is a string
that will be
placed at the top
of the test file
that will be compiled
to check if the function exists;
the default is empty.
The optional
language
argument should be
C
or
C++
and selects the compiler to be used for the check;
the default is "C".
The optional
expect
argument should be an integer.
If this argument is used,
the function will only check whether the type
given in type_name has the expected size (in bytes).
For example,
CheckTypeSize('short', expect = 2)
will return success only if short is two bytes.
-
- SConf.CheckDeclaration(context, symbol, [includes, language])
- sconf.CheckDeclaration(symbol, [includes, language])
-
Checks if the specified
symbol
is declared.
includes
is a string containing one or more
#include
lines that will be inserted into the program
that will be run to test for the existence of the type.
The optional
language
argument should be
C
or
C++
and selects the compiler to be used for the check;
the default is "C".
- SConf.Define(context, symbol, [value, comment])
- sconf.Define(symbol, [value, comment])
-
This function does not check for anything, but defines a
preprocessor symbol that will be added to the configuration header file.
It is the equivalent of AC_DEFINE,
and defines the symbol
name
with the optional
value
and the optional comment
comment.
-
Examples:
-
env = Environment() conf = Configure( env ) # Puts the following line in the config header file: # #define A_SYMBOL conf.Define('A_SYMBOL') # Puts the following line in the config header file: # #define A_SYMBOL 1 conf.Define('A_SYMBOL', 1)
-
-
Be careful about quoting string values, though:
-
env = Environment() conf = Configure( env ) # Puts the following line in the config header file: # #define A_SYMBOL YA conf.Define('A_SYMBOL', "YA") # Puts the following line in the config header file: # #define A_SYMBOL "YA" conf.Define('A_SYMBOL', '"YA"')
-
-
For comment:
-
env = Environment() conf = Configure( env ) # Puts the following lines in the config header file: # /* Set to 1 if you have a symbol */ # #define A_SYMBOL 1 conf.Define('A_SYMBOL', 1, 'Set to 1 if you have a symbol')
You can define your own custom checks. in addition to the predefined checks. These are passed in a dictionary to the Configure function. This dictionary maps the names of the checks to user defined Python callables (either Python functions or class instances implementing the __call__ method). The first argument of the call is always a CheckContext instance followed by the arguments, which must be supplied by the user of the check. These CheckContext instances define the following methods:
-
- CheckContext.Message(self, text)
-
Usually called before the check is started. text will be displayed to the user, e.g. 'Checking for library X...'
- CheckContext.Result(self,, res)
-
Usually called after the check is done. res can be either an integer or a string. In the former case, 'yes' (res != 0) or 'no' (res == 0) is displayed to the user, in the latter case the given string is displayed.
- CheckContext.TryCompile(self, text, extension)
-
Checks if a file with the specified
extension
(e.g. '.c') containing
text
can be compiled using the environment's
Object
builder. Returns 1 on success and 0 on failure.
- CheckContext.TryLink(self, text, extension)
-
Checks, if a file with the specified
extension
(e.g. '.c') containing
text
can be compiled using the environment's
Program
builder. Returns 1 on success and 0 on failure.
- CheckContext.TryRun(self, text, extension)
-
Checks, if a file with the specified
extension
(e.g. '.c') containing
text
can be compiled using the environment's
Program
builder. On success, the program is run. If the program
executes successfully
(that is, its return status is 0),
a tuple
(1, outputStr)
is returned, where
outputStr
is the standard output of the
program.
If the program fails execution
(its return status is non-zero),
then (0, '') is returned.
- CheckContext.TryAction(self, action, [text, extension])
-
Checks if the specified
action
with an optional source file (contents
text
, extension
extension
= ''
) can be executed.
action
may be anything which can be converted to a
scons
Action.
On success,
(1, outputStr)
is returned, where
outputStr
is the content of the target file.
On failure
(0, '')
is returned.
- CheckContext.TryBuild(self, builder, [text, extension])
-
Low level implementation for testing specific builds;
the methods above are based on this method.
Given the Builder instance
builder
and the optional
text
of a source file with optional
extension,
this method returns 1 on success and 0 on failure. In addition,
self.lastTarget
is set to the build target node, if the build was successful.
Example for implementing and using custom tests:
-
def CheckQt(context, qtdir): context.Message( 'Checking for qt ...' ) lastLIBS = context.env['LIBS'] lastLIBPATH = context.env['LIBPATH'] lastCPPPATH= context.env['CPPPATH'] context.env.Append(LIBS = 'qt', LIBPATH = qtdir + '/lib', CPPPATH = qtdir + '/include' ) ret = context.TryLink(""" #include <qapp.h> int main(int argc, char **argv) { QApplication qapp(argc, argv); return 0; } """) if not ret: context.env.Replace(LIBS = lastLIBS, LIBPATH=lastLIBPATH, CPPPATH=lastCPPPATH) context.Result( ret ) return ret env = Environment() conf = Configure( env, custom_tests = { 'CheckQt' : CheckQt } ) if not conf.CheckQt('/usr/lib/qt'): print 'We really need qt!' Exit(1) env = conf.Finish()
-
Command-Line Construction Variables
Often when building software, some variables must be specified at build time. For example, libraries needed for the build may be in non-standard locations, or site-specific compiler options may need to be passed to the compiler. scons provides a Variables object to support overriding construction variables on the command line:
-
$ scons VARIABLE=foo
- Variables([files], [args])
-
This creates a Variables object that will read construction variables from
the file or list of filenames specified in
files.
If no files are specified,
or the
files
argument is
None,
then no files will be read.
The optional argument
args
is a dictionary of
values that will override anything read from the specified files;
it is primarily intended to be passed the
ARGUMENTS
dictionary that holds variables
specified on the command line.
Example:
-
vars = Variables('custom.py') vars = Variables('overrides.py', ARGUMENTS) vars = Variables(None, {FOO:'expansion', BAR:7})
Variables objects have the following methods:
-
- Add(key, [help, default, validator, converter])
-
This adds a customizable construction variable to the Variables object.
key
is the name of the variable.
help
is the help text for the variable.
default
is the default value of the variable;
if the default value is
None
and there is no explicit value specified,
the construction variable will
not
be added to the construction environment.
validator
is called to validate the value of the variable, and should take three
arguments: key, value, and environment.
The recommended way to handle an invalid value is
to raise an exception (see example below).
converter
is called to convert the value before putting it in the environment, and
should take either a value, or the value and environment, as parameters.
The
converter
must return a value,
which will be converted into a string
before being validated by the
validator
(if any)
and then added to the environment.
Examples:
-
vars.Add('CC', 'The C compiler') def validate_color(key, val, env): if not val in ['red', 'blue', 'yellow']: raise Exception("Invalid color value '%s'" % val) vars.Add('COLOR', validator=valid_color)
-
- AddVariables(list)
-
A wrapper script that adds
multiple customizable construction variables
to a Variables object.
list
is a list of tuple or list objects
that contain the arguments
for an individual call to the
Add
method.
-
opt.AddVariables( ('debug', '', 0), ('CC', 'The C compiler'), ('VALIDATE', 'An option for testing validation', 'notset', validator, None), )
-
- Update(env, [args])
-
This updates a construction environment
env
with the customized construction variables.
Any specified variables that are
not
configured for the Variables object
will be saved and may be
retrieved with the
UnknownVariables()
method, below.
Normally this method is not called directly, but is called indirectly by passing the Variables object to the Environment() function:
-
env = Environment(variables=vars)
-
-
The text file(s) that were specified
when the Variables object was created
are executed as Python scripts,
and the values of (global) Python variables set in the file
are added to the construction environment.
Example:
-
CC = 'my_cc'
-
- UnknownVariables()
-
Returns a dictionary containing any
variables that were specified
either in the files or the dictionary
with which the Variables object was initialized,
but for which the Variables object was
not configured.
-
env = Environment(variables=vars) for key, value in vars.UnknownVariables(): print "unknown variable: %s=%s" % (key, value)
-
- Save(filename, env)
-
This saves the currently set variables into a script file named
filename
that can be used on the next invocation to automatically load the current
settings. This method combined with the Variables method can be used to
support caching of variables between runs.
-
env = Environment() vars = Variables(['variables.cache', 'custom.py']) vars.Add(...) vars.Update(env) vars.Save('variables.cache', env)
-
- GenerateHelpText(env, [sort])
-
This generates help text documenting the customizable construction
variables suitable to passing in to the Help() function.
env
is the construction environment that will be used to get the actual values
of customizable variables. Calling with
an optional
sort
function
will cause the output to be sorted
by the specified argument.
The specific
sort
function
should take two arguments
and return
-1, 0 or 1
(like the standard Python
cmp
function).
-
Help(vars.GenerateHelpText(env)) Help(vars.GenerateHelpText(env, sort=cmp))
-
- FormatVariableHelpText(env, opt, help, default, actual)
-
This method returns a formatted string
containing the printable help text
for one option.
It is normally not called directly,
but is called by the
GenerateHelpText()
method to create the returned help text.
It may be overridden with your own
function that takes the arguments specified above
and returns a string of help text formatted to your liking.
Note that the
GenerateHelpText()
will not put any blank lines or extra
characters in between the entries,
so you must add those characters to the returned
string if you want the entries separated.
-
def my_format(env, opt, help, default, actual): fmt = "s: default=%s actual=%s (%s) return fmt % (opt, default. actual, help) vars.FormatVariableHelpText = my_format
To make it more convenient to work with customizable Variables, scons provides a number of functions that make it easy to set up various types of Variables:
-
- BoolVariable(key, help, default)
-
Return a tuple of arguments
to set up a Boolean option.
The option will use
the specified name
key,
have a default value of
default,
and display the specified
help
text.
The option will interpret the values
y,
yes,
t,
true,
1,
on
and
all
as true,
and the values
n,
no,
f,
false,
0,
off
and
none
as false.
- EnumVariable(key, help, default, allowed_values, [map, ignorecase])
-
Return a tuple of arguments
to set up an option
whose value may be one
of a specified list of legal enumerated values.
The option will use
the specified name
key,
have a default value of
default,
and display the specified
help
text.
The option will only support those
values in the
allowed_values
list.
The optional
map
argument is a dictionary
that can be used to convert
input values into specific legal values
in the
allowed_values
list.
If the value of
ignore_case
is
0
(the default),
then the values are case-sensitive.
If the value of
ignore_case
is
1,
then values will be matched
case-insensitive.
If the value of
ignore_case
is
1,
then values will be matched
case-insensitive,
and all input values will be
converted to lower case.
- ListVariable(key, help, default, names, [,map])
-
Return a tuple of arguments
to set up an option
whose value may be one or more
of a specified list of legal enumerated values.
The option will use
the specified name
key,
have a default value of
default,
and display the specified
help
text.
The option will only support the values
all,
none,
or the values in the
names
list.
More than one value may be specified,
with all values separated by commas.
The default may be a string of
comma-separated default values,
or a list of the default values.
The optional
map
argument is a dictionary
that can be used to convert
input values into specific legal values
in the
names
list.
- PackageVariable(key, help, default)
-
Return a tuple of arguments
to set up an option
whose value is a path name
of a package that may be
enabled, disabled or
given an explicit path name.
The option will use
the specified name
key,
have a default value of
default,
and display the specified
help
text.
The option will support the values
yes,
true,
on,
enable
or
search,
in which case the specified
default
will be used,
or the option may be set to an
arbitrary string
(typically the path name to a package
that is being enabled).
The option will also support the values
no,
false,
off
or
disable
to disable use of the specified option.
- PathVariable(key, help, default, [validator])
-
Return a tuple of arguments
to set up an option
whose value is expected to be a path name.
The option will use
the specified name
key,
have a default value of
default,
and display the specified
help
text.
An additional
validator
may be specified
that will be called to
verify that the specified path
is acceptable.
SCons supplies the
following ready-made validators:
PathVariable.PathExists
(the default),
which verifies that the specified path exists;
PathVariable.PathIsFile,
which verifies that the specified path is an existing file;
PathVariable.PathIsDir,
which verifies that the specified path is an existing directory;
PathVariable.PathIsDirCreate,
which verifies that the specified path is a directory
and will create the specified directory if the path does not exist;
and
PathVariable.PathAccept,
which simply accepts the specific path name argument without validation,
and which is suitable if you want your users
to be able to specify a directory path that will be
created as part of the build process, for example.
You may supply your own
validator
function,
which must take three arguments
(key,
the name of the variable to be set;
val,
the specified value being checked;
and
env,
the construction environment)
and should raise an exception
if the specified value is not acceptable.
These functions make it convenient to create a number of variables with consistent behavior in a single call to the AddVariables method:
-
vars.AddVariables( BoolVariable('warnings', 'compilation with -Wall and similiar', 1), EnumVariable('debug', 'debug output and symbols', 'no' allowed_values=('yes', 'no', 'full'), map={}, ignorecase=0), # case sensitive ListVariable('shared', 'libraries to build as shared libraries', 'all', names = list_of_libs), PackageVariable('x11', 'use X11 installed here (yes = search some places)', 'yes'), PathVariable('qtdir', 'where the root of Qt is installed', qtdir), PathVariable('foopath', 'where the foo library is installed', foopath, PathVariable.PathIsDir), )
-
File and Directory Nodes
The File() and Dir() functions return File and Dir Nodes, respectively. python objects, respectively. Those objects have several user-visible attributes and methods that are often useful:
- path
-
The build path
of the given
file or directory.
This path is relative to the top-level directory
(where the
SConstruct
file is found).
The build path is the same as the source path if
variant_dir
is not being used.
- abspath
-
The absolute build path of the given file or directory.
- srcnode()
-
The
srcnode()
method
returns another
File
or
Dir
object representing the
source
path of the given
File
or
Dir.
The
-
# Get the current build dir's path, relative to top. Dir('.').path # Current dir's absolute path Dir('.').abspath # Next line is always '.', because it is the top dir's path relative to itself. Dir('#.').path File('foo.c').srcnode().path # source path of the given source file. # Builders also return File objects: foo = env.Program('foo.c') print "foo will be built in %s"%foo.path
A Dir Node or File Node can also be used to create file and subdirectory Nodes relative to the generating Node. A Dir Node will place the new Nodes within the directory it represents. A File node will place the new Nodes within its parent directory (that is, "beside" the file in question). If d is a Dir (directory) Node and f is a File (file) Node, then these methods are available:
-
- d.Dir(name)
-
Returns a directory Node for a subdirectory of
d
named
name.
- d.File(name)
-
Returns a file Node for a file within
d
named
name.
- d.Entry(name)
-
Returns an unresolved Node within
d
named
name.
- f.Dir(name)
-
Returns a directory named
name
within the parent directory of
f.
- f.File(name)
-
Returns a file named
name
within the parent directory of
f.
- f.Entry(name)
-
Returns an unresolved Node named
name
within the parent directory of
f.
For example:
-
# Get a Node for a file within a directory incl = Dir('include') f = incl.File('header.h') # Get a Node for a subdirectory within a directory dist = Dir('project-3.2.1) src = dist.Dir('src') # Get a Node for a file in the same directory cfile = File('sample.c') hfile = cfile.File('sample.h') # Combined example docs = Dir('docs') html = docs.Dir(') index =.File('index') css = index.File('app.css')
-
EXTENDING SCONS
Builder Objects
scons can be extended to build different types of targets by adding new Builder objects to a construction environment. In general, you should only need to add a new Builder object when you want to build a new type of file or other external target. If you just want to invoke a different compiler or other tool to build a Program, Object, Library, or any other type of output file for which scons already has an existing Builder, it is generally much easier to use those existing Builders in a construction environment that sets the appropriate construction variables (CC, LINK, etc.).Builder objects are created using the Builder function. The Builder function accepts the following arguments:
- action
-
The command line string used to build the target from the source.
action
can also be:
a list of strings representing the command
to be executed and its arguments
(suitable for enclosing white space in an argument),
a dictionary
mapping source file name suffixes to
any combination of command line strings
(if the builder should accept multiple source file extensions),
a Python function;
an Action object
(see the next section);
or a list of any of the above.
An action function takes three arguments: source - a list of source nodes, target - a list of target nodes, env - the construction environment.
- prefix
-
The prefix that will be prepended to the target file name.
This may be specified as a:
-
-
*
string,
- * callable object - a function or other callable that takes
- two arguments (a construction environment and a list of sources)
and returns a prefix,
- * dictionary - specifies a mapping from a specific source suffix (of the first
- source specified) to a corresponding target prefix. Both the source suffix and target prefix specifications may use environment variable substitution, and the target prefix (the 'value' entries in the dictionary) may also be a callable object. The default target prefix may be indicated by a dictionary entry with a key value of None.
-
*
string,
-
b = Builder("build_it < $SOURCE > $TARGET", prefix = "file-") def gen_prefix(env, sources): return "file-" + env['PLATFORM'] + '-' b = Builder("build_it < $SOURCE > $TARGET", prefix = gen_prefix) b = Builder("build_it < $SOURCE > $TARGET", suffix = { None: "file-", "$SRC_SFX_A": gen_prefix })
-
- suffix
-
The suffix that will be appended to the target file name.
This may be specified in the same manner as the prefix above.
If the suffix is a string, then
scons
will append a '.' to the beginning of the suffix if it's not already
there. The string returned by callable object (or obtained from the
dictionary) is untouched and must append its own '.' to the beginning
if one is desired.
-
b = Builder("build_it < $SOURCE > $TARGET" suffix = "-file") def gen_suffix(env, sources): return "." + env['PLATFORM'] + "-file" b = Builder("build_it < $SOURCE > $TARGET", suffix = gen_suffix) b = Builder("build_it < $SOURCE > $TARGET", suffix = { None: ".sfx1", "$SRC_SFX_A": gen_suffix })
-
- ensure_suffix
-
When set to any true value, causes
scons
to add the target suffix specified by the
suffix
keyword to any target strings
that have a different suffix.
(The default behavior is to leave untouched
any target file name that looks like it already has any suffix.)
-
b1 = Builder("build_it < $SOURCE > $TARGET" suffix = ".out") b2 = Builder("build_it < $SOURCE > $TARGET" suffix = ".out", ensure_suffix) env = Environment() env['BUILDERS']['B1'] = b1 env['BUILDERS']['B2'] = b2 # Builds "foo.txt" because ensure_suffix is not set. env.B1('foo.txt', 'foo.in') # Builds "bar.txt.out" because ensure_suffix is set. env.B2('bar.txt', 'bar.in')
-
- src_suffix
-
The expected source file name suffix. This may be a string or a list
of strings.
- target_scanner
-
A Scanner object that
will be invoked to find
implicit dependencies for this target file.
This keyword argument should be used
for Scanner objects that find
implicit dependencies
based only on the target file
and the construction environment,
not
for implicit
(See the section "Scanner Objects," below,
for information about creating Scanner objects.)
- source_scanner
-
A Scanner object that
will be invoked to
find implicit dependences in
any source files
used to build this target file.
This is where you would
specify a scanner to
find things like
#include
lines in source files.
The pre-built
DirScanner
Scanner object may be used to
indicate that this Builder
should scan directory trees
for on-disk changes to files
that
scons
does not know about from other Builder or function calls.
(See the section "Scanner Objects," below,
for information about creating your own Scanner objects.)
- target_factory
-
A factory function that the Builder will use
to turn any targets specified as strings into SCons Nodes.
By default,
SCons assumes that all targets are files.
Other useful target_factory
values include
Dir,
for when a Builder creates a directory target,
and
Entry,
for when a Builder can create either a file
or directory target.
Example:
-
MakeDirectoryBuilder = Builder(action=my_mkdir, target_factory=Dir) env = Environment() env.Append(BUILDERS = {'MakeDirectory':MakeDirectoryBuilder}) env.MakeDirectory('new_directory', [])
-
-
Note that the call to the MakeDirectory Builder
needs to specify an empty source list
to make the string represent the builder's target;
without that, it would assume the argument is the source,
and would try to deduce the target name from it,
which in the absence of an automatically-added prefix or suffix
would lead to a matching target and source name
and a circular dependency.
- source_factory
-
A factory function that the Builder will use
to turn any sources specified as strings into SCons Nodes.
By default,
SCons assumes that all source are files.
Other useful source_factory
values include
Dir,
for when a Builder uses a directory as a source,
and
Entry,
for when a Builder can use files
or directories (or both) as sources.
Example:
-
CollectBuilder = Builder(action=my_mkdir, source_factory=Entry) env = Environment() env.Append(BUILDERS = {'Collect':CollectBuilder}) env.Collect('archive', ['directory_name', 'file_name'])
-
- emitter
-
A function or list of functions to manipulate the target and source
lists before dependencies are established
and the target(s) are actually built.
emitter
can also be a string containing a construction variable to expand
to an emitter function or list of functions,
or a dictionary mapping source file suffixes
to emitter functions.
(Only the suffix of the first source file
is used to select the actual emitter function
from an emitter dictionary.)
An emitter function takes three arguments: source - a list of source nodes, target - a list of target nodes, env - the construction environment. An emitter must return a tuple containing two lists, the list of targets to be built by this builder, and the list of sources for this builder.
Example:
-
def e(target, source, env): return (target + ['foo.foo'], source + ['foo.src']) # Simple association of an emitter function with a Builder. b = Builder("my_build < $TARGET > $SOURCE", emitter = e) def e2(target, source, env): return (target + ['bar.foo'], source + ['bar.src']) # Simple association of a list of emitter functions with a Builder. b = Builder("my_build < $TARGET > $SOURCE", emitter = [e, e2]) # Calling an emitter function through a construction variable. env = Environment(MY_EMITTER = e) b = Builder("my_build < $TARGET > $SOURCE", emitter = '$MY_EMITTER') # Calling a list of emitter functions through a construction variable. env = Environment(EMITTER_LIST = [e, e2]) b = Builder("my_build < $TARGET > $SOURCE", emitter = '$EMITTER_LIST') # Associating multiple emitters with different file # suffixes using a dictionary. def e_suf1(target, source, env): return (target + ['another_target_file'], source) def e_suf2(target, source, env): return (target, source + ['another_source_file']) b = Builder("my_build < $TARGET > $SOURCE", emitter = {'.suf1' : e_suf1, '.suf2' : e_suf2})
-
- multi
-
Specifies whether this builder is allowed to be called multiple times for
the same target file(s). The default is 0, which means the builder
can not be called multiple times for the same target file(s). Calling a
builder multiple times for the same target simply adds additional source
files to the target; it is not allowed to change the environment associated
with the target, specify addition environment overrides, or associate a different
builder with the target.
- env
-
A construction environment that can be used
to fetch source code using this Builder.
(Note that this environment is
not
used for normal builds of normal target files,
which use the environment that was
used to call the Builder for the target file.)
- generator
-
A function that returns a list of actions that will be executed to build
the target(s) from the source(s).
The returned action(s) may be
an Action object, or anything that
can be converted into an Action object
(see the next section).
The generator function takes four arguments: source - a list of source nodes, target - a list of target nodes, env - the construction environment, for_signature - a Boolean value that specifies whether the generator is being called for generating a build signature (as opposed to actually executing the command). Example:
-
def g(source, target, env, for_signature): return [["gcc", "-c", "-o"] + target + source] b = Builder(generator=g)
-
-
The
generator
and
action
arguments must not both be used for the same Builder.
- src_builder
-
Specifies a builder to use when a source file name suffix does not match
any of the suffixes of the builder. Using this argument produces a
multi-stage builder.
- single_source
-
Specifies that this builder expects exactly one source file per call. Giving
more than one source file without target files results in implicitely calling
the builder multiple times (once for each source given). Giving multiple
source files together with target files results in a UserError exception.
-
The
generator
and
action
arguments must not both be used for the same Builder.
- source_ext_match
-
When the specified
action
argument is a dictionary,
the default behavior when a builder is passed
multiple source files is to make sure that the
extensions of all the source files match.
If it is legal for this builder to be
called with a list of source files with different extensions,
this check can be suppressed by setting
source_ext_match
to
None
or some other non-true value.
When
source_ext_match
is disable,
scons
will use the suffix of the first specified
source file to select the appropriate action from the
action
dictionary.
In the following example, the setting of source_ext_match prevents scons from exiting with an error due to the mismatched suffixes of foo.in and foo.extra.
-
b = Builder(action={'.in' : 'build $SOURCES > $TARGET'}, source_ext_match = None) env = Environment(BUILDERS = {'MyBuild':b}) env.MyBuild('foo.out', ['foo.in', 'foo.extra'])
-
- env
-
A construction environment that can be used
to fetch source code using this Builder.
(Note that this environment is
not
used for normal builds of normal target files,
which use the environment that was
used to call the Builder for the target file.)
-
b = Builder(action="build < $SOURCE > $TARGET") env = Environment(BUILDERS = {'MyBuild' : b}) env.MyBuild('foo.out', 'foo.in', my_arg = 'xyzzy')
-
- chdir
-
A directory from which scons
will execute the
action(s) specified
for this Builder.
If the
chdir
argument is
a string or a directory Node,
scons will change to the specified directory.
If the
chdir
is not a string or Node
and is non-zero,
then scons will change to the
target file's directory.
Note that scons will not automatically modify its expansion of construction variables like $TARGET and $SOURCE when using the chdir keyword argument--that is, the expanded file names will still be relative to the top-level SConstruct directory, and consequently incorrect relative to the chdir directory. Builders created using chdir keyword argument, will need to use construction variable expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the targets and source.
-
b = Builder(action="build < ${SOURCE.file} > ${TARGET.file}", chdir=1) env = Environment(BUILDERS = {'MyBuild' : b}) env.MyBuild('sub/dir/foo.out', 'sub/dir/foo.in')
WARNING: Python only keeps one current directory location for all of the threads. This means that use of the chdir argument will not work with the SCons -j option, because individual worker threads spawned by SCons interfere with each other when they start changing directory.
Any additional keyword arguments supplied when a Builder object is created (that is, when the Builder() function is called) will be set in the executing construction environment when the Builder object is called. The canonical example here would be to set a construction variable to the repository of a source code system.
Any additional keyword arguments supplied when a Builder object is called will only be associated with the target created by that particular Builder call (and any other files built as a result of the call).
These extra keyword arguments are passed to the following functions: command generator functions, function Actions, and emitter functions.
-
Action Objects
The Builder() function will turn its action keyword argument into an appropriate internal Action object. You can also explicity create Action objects using the Action() global function, which can then be passed to the Builder() function. This can be used to configure an Action object more flexibly, or it may simply be more efficient than letting each separate Builder object create a separate Action when multiple Builder objects need to do the same thing.
The Action() global function returns an appropriate object for the action represented by the type of the first argument:
- Action
-
If the first argument is already an Action object,
the object is simply returned.
- String
-
If the first argument is a string,
a command-line Action is returned.
Note that the command-line string
may be preceded by an
@
(at-sign)
to suppress printing of the specified command line,
or by a
-
(hyphen)
to ignore the exit status from the specified command:
-
Action('$CC -c -o $TARGET $SOURCES') # Doesn't print the line being executed. Action('@build $TARGET $SOURCES') # Ignores return value Action('-build $TARGET $SOURCES')
-
- List
-
If the first argument is a list,
then a list of Action objects is returned.
An Action object is created as necessary
for each element in the list.
If an element
within
the list is itself a list,
the internal list is the
command and arguments to be executed via
the command line.
This allows white space to be enclosed
in an argument by defining
a command in a list within a list:
-
Action([['cc', '-c', '-DWHITE SPACE', '-o', '$TARGET', '$SOURCES']])
-
- Function
-
If the first argument is a Python function,
a function Action is returned.
The Python function must take three keyword arguments,
target
(a Node object representing the target file),
source
(a Node object representing the source file)
and
env
(the construction environment
used for building the target file).
The
target
and
source
arguments may be lists of Node objects if there is
more than one target file or source file.
The actual target and source file name(s) may
be retrieved from their Node objects
via the built-in Python str() function:
-
target_file_name = str(target) source_file_names = map(lambda x: str(x), source)
-
-
The function should return
0
or
None
to indicate a successful build of the target file(s).
The function may raise an exception
or return a non-zero exit status
to indicate an unsuccessful build.
-
def build_it(target = None, source = None, env = None): # build the target from the source return 0 a = Action(build_it)
If the action argument is not one of the above, None is returned.
-
The second argument is optional and is used to define the output which is printed when the Action is actually performed. In the absence of this parameter, or if it's an empty string, a default output depending on the type of the action is used. For example, a command-line action will print the executed command. The argument must be either a Python function or a string.
In the first case, it's a function that returns a string to be printed to describe the action being executed. The function may also be specified by the strfunction= keyword argument. Like a function to build a file, this function must take three keyword arguments: target (a Node object representing the target file), source (a Node object representing the source file) and env (a construction environment). The target and source arguments may be lists of Node objects if there is more than one target file or source file.
In the second case, you provide the string itself. The string may also be specified by the cmdstr= keyword argument. The string typically contains variables, notably $TARGET(S) and $SOURCE(S), or consists of just a single variable, which is optionally defined somewhere else. SCons itself heavily uses the latter variant.
Examples:
-
def build_it(target, source, env): # build the target from the source return 0 def string_it(target, source, env): return "building '%s' from '%s'" % (target[0], source[0]) # Use a positional argument. f = Action(build_it, string_it) s = Action(build_it, "building '$TARGET' from '$SOURCE'") # Alternatively, use a keyword argument. f = Action(build_it, strfunction=string_it) s = Action(build_it, cmdstr="building '$TARGET' from '$SOURCE'") # You can provide a configurable variable. l = Action(build_it, '$STRINGIT')
The third and succeeding arguments, if present, may either be a construction variable or a list of construction variables whose values will be included in the signature of the Action when deciding whether a target should be rebuilt because the action changed. The variables may also be specified by a varlist= keyword parameter; if both are present, they are combined. This is necessary whenever you want a target to be rebuilt when a specific construction variable changes. This is not often needed for a string action, as the expanded variables will normally be part of the command line, but may be needed if a Python function action uses the value of a construction variable when generating the command line.
-
def build_it(target, source, env): # build the target from the 'XXX' construction variable open(target[0], 'w').write(env['XXX']) return 0 # Use positional arguments. a = Action(build_it, '$STRINGIT', ['XXX']) # Alternatively, use a keyword argument. a = Action(build_it, varlist=['XXX'])
The Action() global function can be passed the following optional keyword arguments to modify the Action object's behavior:
-
chdir
The
chdir
keyword argument specifies that
scons will execute the action
after changing to the specified directory.
If the
chdir
argument is
a string or a directory Node,
scons will change to the specified directory.
If the
chdir
argument
is not a string or Node
and is non-zero,
then scons will change to the
target file's directory.
Note that scons will not automatically modify its expansion of construction variables like $TARGET and $SOURCE when using the chdir keyword argument--that is, the expanded file names will still be relative to the top-level SConstruct directory, and consequently incorrect relative to the chdir directory. Builders created using chdir keyword argument, will need to use construction variable expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the targets and source.
-
a = Action("build < ${SOURCE.file} > ${TARGET.file}", chdir=1)
-
-
exitstatfunc
The
Action()
global function
also takes an
exitstatfunc
keyword argument
which specifies a function
that is passed the exit status
(or return value)
from the specified action
and can return an arbitrary
or modified value.
This can be used, for example,
to specify that an Action object's
return value should be ignored
under special conditions
and SCons should, therefore,
consider that the action always suceeds:
-
def always_succeed(s): # Always return 0, which indicates success. return 0 a = Action("build < ${SOURCE.file} > ${TARGET.file}", exitstatfunc=always_succeed)
-
-
batch_key
The
batch_key
keyword argument can be used
to specify that the Action can create multiple target files
by processing multiple independent source files simultaneously.
(The canonical example is "batch compilation"
of multiple object files
by passing multiple source files
to a single invocation of a compiler
such as Microsoft's Visual C / C++ compiler.)
If the
batch_key
argument is any non-False, non-callable Python value,
the configured Action object will cause
scons
to collect all targets built with the Action object
and configured with the same construction environment
into single invocations of the Action object's
command line or function.
Command lines will typically want to use the
CHANGED_SOURCES
construction variable
(and possibly
CHANGED_TARGETS
as well)
to only pass to the command line those sources that
have actually changed since their targets were built.
Example:
-
a = Action('build $CHANGED_SOURCES', batch_key=True)
The batch_key argument may also be a callable function that returns a key that will be used to identify different "batches" of target files to be collected for batch building. A batch_key function must take the following arguments:
-
- action
-
The action object.
- env
-
The construction environment
configured for the target.
- target
-
The list of targets for a particular configured action.
- source
-
The list of source for a particular configured action.
The returned key should typically be a tuple of values derived from the arguments, using any appropriate logic to decide how multiple invocations should be batched. For example, a batch_key function may decide to return the value of a specific construction variable from the env argument which will cause scons to batch-build targets with matching values of that variable, or perhaps return the id() of the entire construction environment, in which case scons will batch-build all targets configured with the same construction environment. Returning None indicates that the particular target should not be part of any batched build, but instead will be built by a separate invocation of action's command or function. Example:
-
def batch_key(action, env, target, source): tdir = target[0].dir if tdir.name == 'special': # Don't batch-build any target # in the special/ subdirectory. return None return (id(action), id(env), tdir) a = Action('build $CHANGED_SOURCES', batch_key=batch_key)
-
Miscellaneous Action Functions
scons supplies a number of functions that arrange for various common file and directory manipulations to be performed. These are similar in concept to "tasks" in the Ant build tool, although the implementation is slightly different. These functions do not actually perform the specified action at the time the function is called, but instead return an Action object that can be executed at the appropriate time. (In Object-Oriented terminology, these are actually Action Factory functions that return Action objects.)
In practice, there are two natural ways that these Action Functions are intended to be used.
First, if you need to perform the action at the time the SConscript file is being read, you can use the Execute global function to do so:
-
Execute(Touch('file'))
Second, you can use these functions to supply Actions in a list for use by the Command method. This can allow you to perform more complicated sequences of file manipulation without relying on platform-specific external commands: that
-
env = Environment(TMPBUILD = '/tmp/builddir') env.Command('foo.out', 'foo.in', [Mkdir('$TMPBUILD'), Copy('$TMPBUILD', '${SOURCE.dir}'), "cd $TMPBUILD && make", Delete('$TMPBUILD')])
- Chmod(dest, mode)
-
Returns an Action object that
changes the permissions on the specified
dest
file or directory to the specified
mode.
Examples:
-
Execute(Chmod('file', 0755)) env.Command('foo.out', 'foo.in', [Copy('$TARGET', '$SOURCE'), Chmod('$TARGET', 0755)])
-
- Copy(dest, src)
-
Returns an Action object
that will copy the
src
source file or directory to the
dest
destination file or directory.
Examples:
-
Execute(Copy('foo.output', 'foo.input')) env.Command('bar.out', 'bar.in', Copy('$TARGET', '$SOURCE'))
-
- Delete(entry, [must_exist])
-
Returns an Action that
deletes the specified
entry,
which may be a file or a directory tree.
If a directory is specified,
the entire directory tree
will be removed.
If the
must_exist
flag is set,
then a Python error will be thrown
if the specified entry does not exist;
the default is
must_exist=0,
that is, the Action will silently do nothing
if the entry does not exist.
Examples:
-
Execute(Delete('/tmp/buildroot')) env.Command('foo.out', 'foo.in', [Delete('${TARGET.dir}'), MyBuildAction]) Execute(Delete('file_that_must_exist', must_exist=1))
-
- Mkdir(dir)
-
Returns an Action
that creates the specified
directory
dir .
Examples:
-
Execute(Mkdir('/tmp/outputdir')) env.Command('foo.out', 'foo.in', [Mkdir('/tmp/builddir'), Copy('/tmp/builddir/foo.in', '$SOURCE'), "cd /tmp/builddir && make", Copy('$TARGET', '/tmp/builddir/foo.out')])
-
- Move(dest, src)
-
Returns an Action
that moves the specified
src
file or directory to
the specified
dest
file or directory.
Examples:
-
Execute(Move('file.destination', 'file.source')) env.Command('output_file', 'input_file', [MyBuildAction, Move('$TARGET', 'file_created_by_MyBuildAction')])
-
- Touch(file)
-
Returns an Action
that updates the modification time
on the specified
file.
Examples:
-
Execute(Touch('file_to_be_touched')) env.Command('marker', 'input_file', [MyBuildAction, Touch('$TARGET')])
-
Variable Substitution
Before executing a command, scons performs construction variable interpolation on the strings that make up the command line of builders. Variables are introduced by a $ prefix. Besides construction variables, scons provides the following variables for each command execution:
- CHANGED_SOURCES
-
The file names of all sources of the build command
that have changed since the target was last built.
- CHANGED_TARGETS
-
The file names of all targets that would be built
from sources that have changed since the target was last built.
- SOURCE
-
The file name of the source of the build command,
or the file name of the first source
if multiple sources are being built.
- SOURCES
-
The file names of the sources of the build command.
- TARGET
-
The file name of the target being built,
or the file name of the first target
if multiple targets are being built.
- TARGETS
-
The file names of all targets being built.
- UNCHANGED_SOURCES
-
The file names of all sources of the build command
that have
not
changed since the target was last built.
- UNCHANGED_TARGETS
-
The file names of all targets that would be built
from sources that have
not
changed since the target was last built.
(Note that the above variables are reserved and may not be set in a construction environment.)
For example, given the construction variable CC='cc', targets=['foo'], and sources=['foo.c', 'bar.c']:
-
action='$CC -c -o $TARGET $SOURCES'
would produce the command line:
-
cc -c -o foo foo.c bar.c
Variable names may be surrounded by curly braces ({}) to separate the name from the trailing characters. Within the curly braces, a variable name may have a Python slice subscript appended to select one or more items from a list. In the previous example, the string:
-
${SOURCES[1]}
would produce:
-
bar.c
Additionally, a variable name may have the following special modifiers appended within the enclosing curly braces to modify the interpolated string:
- base
-
The base path of the file name,
including the directory path
but excluding any suffix.
- dir
-
The name of the directory in which the file exists.
- file
-
The file name,
minus any directory portion.
- filebase
-
Just the basename of the file,
minus any suffix
and minus the directory.
- suffix
-
Just the file suffix.
- abspath
-
The absolute path name of the file.
- posix
-
The POSIX form of the path,
with directories separated by
/
(forward slashes)
not backslashes.
This is sometimes necessary on Windows systems
when a path references a file on other (POSIX) systems.
- srcpath
-
The directory and file name to the source file linked to this file through
VariantDir().
If this file isn't linked,
it just returns the directory and filename unchanged.
- srcdir
-
The directory containing the source file linked to this file through
VariantDir().
If this file isn't linked,
it just returns the directory part of the filename.
- rsrcpath
-
The directory and file name to the source file linked to this file through
VariantDir().
If the file does not exist locally but exists in a Repository,
the path in the Repository is returned.
If this file isn't linked, it just returns the
directory and filename unchanged.
- rsrcdir
-
The Repository directory containing the source file linked to this file through
VariantDir().
If this file isn't linked,
it just returns the directory part of the filename.
For example, the specified target will expand as follows for the corresponding modifiers:
-
$TARGET => sub/dir/file.x ${TARGET.base} => sub/dir/file ${TARGET.dir} => sub/dir ${TARGET.file} => file.x ${TARGET.filebase} => file ${TARGET.suffix} => .x ${TARGET.abspath} => /top/dir/sub/dir/file.x SConscript('src/SConscript', variant_dir='sub/dir') $SOURCE => sub/dir/file.x ${SOURCE.srcpath} => src/file.x ${SOURCE.srcdir} => src Repository('/usr/repository') $SOURCE => sub/dir/file.x ${SOURCE.rsrcpath} => /usr/repository/src/file.x ${SOURCE.rsrcdir} => /usr/repository/src
Note that curly braces braces may also be used to enclose arbitrary Python code to be evaluated. (In fact, this is how the above modifiers are substituted, they are simply attributes of the Python objects that represent TARGET, SOURCES, etc.) See the section "Python Code Substitution," below, for more thorough examples of how this can be used.
Lastly, a variable name may be a callable Python function associated with a construction variable in the environment. The function should take four arguments: target - a list of target nodes, source - a list of source nodes, env - the construction environment, for_signature - a Boolean value that specifies whether the function is being called for generating a build signature. SCons will insert whatever the called function returns into the expanded string:
-
def foo(target, source, env, for_signature): return "bar" # Will expand $BAR to "bar baz" env=Environment(FOO=foo, BAR="$FOO baz")
You can use this feature to pass arguments to a Python function by creating a callable class that stores one or more arguments in an object, and then uses them when the __call__() method is called. Note that in this case, the entire variable expansion must be enclosed by curly braces so that the arguments will be associated with the instantiation of the class:
-
class foo(object): def __init__(self, arg): self.arg = arg def __call__(self, target, source, env, for_signature): return self.arg + " bar" # Will expand $BAR to "my argument bar baz" env=Environment(FOO=foo, BAR="${FOO('my argument')} baz")
The special pseudo-variables $( and $) may be used to surround parts of a command line that may change without causing a rebuild--that is, which are not included in the signature of target files built with this command. All text between $( and $) will be removed from the command line before it is added to file signatures, and the $( and $) will be removed before the command is executed. For example, the command line:
-
echo Last build occurred $( $TODAY $). > $TARGET
would execute the command:
-
echo Last build occurred $TODAY. > $TARGET
but the command signature added to any target files would be:
-
echo Last build occurred . > $TARGET
Python Code Substitution
Any python code within ${-} pairs gets evaluated by python 'eval', with the python globals set to the current environment's set of construction variables. So in the following case:
-
env['COND'] = 0 env.Command('foo.out', 'foo.in', '''echo ${COND==1 and 'FOO' or 'BAR'} > $TARGET''')
-
echo FOO > foo.out
-
echo BAR > foo.out
Here's a more interesting example. Note that all of COND, FOO, and BAR are environment variables, and their values are substituted into the final command. FOO is a list, so its elements are interpolated separated by spaces.
-
env=Environment() env['COND'] = 0 env['FOO'] = ['foo1', 'foo2'] env['BAR'] = 'barbar' env.Command('foo.out', 'foo.in', 'echo ${COND==1 and FOO or BAR} > $TARGET') # Will execute this: # echo foo1 foo2 > foo.out
SCons uses the following rules when converting construction variables into command lines:
- String
-
When the value is a string it is interpreted as a space delimited list of
command line arguments.
- List
-
When the value is a list it is interpreted as a list of command line
arguments. Each element of the list is converted to a string.
- Other
-
Anything that is not a list or string is converted to a string and
interpreted as a single command line argument.
- Newline
-
Newline characters (
) delimit lines. The newline parsing is done after all other parsing, so it is not possible for arguments (e.g. file names) to contain embedded newline characters. This limitation will likely go away in a future version of SCons.
Scanner Objects
You can use the Scanner function to define objects to scan new file types for implicit dependencies. The Scanner function accepts the following arguments:
- function
-
This can be either:
1) a Python function that will process
the Node (file)
and return a list of strings (file names)
representing the implicit
dependencies found in the contents;
or:
2) a dictionary that maps keys
(typically the file suffix, but see below for more discussion)
to other Scanners that should be called.
If the argument is actually a Python function, the function must take three or four arguments:
def scanner_function(node, env, path):
def scanner_function(node, env, path, arg=None):The node argument is the internal SCons node representing the file. Use str(node) to fetch the name of the file, and node.get_contents() to fetch contents of the file. Note that the file is not guaranteed to exist before the scanner is called, so the scanner function should check that if there's any chance that the scanned file might not exist (for example, if it's built from other files).
The env argument is the construction environment for the scan. Fetch values from it using the env.Dictionary() method.
The path argument is a tuple (or list) of directories that can be searched for files. This will usually be the tuple returned by the path_function argument (see below).
The arg argument is the argument supplied when the scanner was created, if any.
- name
-
The name of the Scanner.
This is mainly used
to identify the Scanner internally.
- argument
-
An optional argument that, if specified,
will be passed to the scanner function
(described above)
and the path function
(specified below).
- skeys
-
An optional list that can be used to
determine which scanner should be used for
a given Node.
In the usual case of scanning for file names,
this argument will be a list of suffixes
for the different file types that this
Scanner knows how to scan.
If the argument is a string,
then it will be expanded
into a list by the current environment.
- path_function
-
A Python function that takes four or five arguments:
a construction environment,
a Node for the directory containing
the SConscript file in which
the first target was defined,
a list of target nodes,
a list of source nodes,
and an optional argument supplied
when the scanner was created.
The
path_function
returns a tuple of directories
that can be searched for files to be returned
by this Scanner object.
(Note that the
FindPathDirs()
function can be used to return a ready-made
path_function
for a given construction variable name,
instead of having to write your own function from scratch.)
- node_class
-
The class of Node that should be returned
by this Scanner object.
Any strings or other objects returned
by the scanner function
that are not of this class
will be run through the
node_factory
function.
- node_factory
-
A Python function that will take a string
or other object
and turn it into the appropriate class of Node
to be returned by this Scanner object.
- scan_check
-
An optional Python function that takes two arguments,
a Node (file) and a construction environment,
and returns whether the
Node should, in fact,
be scanned for dependencies.
This check can be used to eliminate unnecessary
calls to the scanner function when,
for example, the underlying file
represented by a Node does not yet exist.
- recursive
-
An optional flag that
specifies whether this scanner should be re-invoked
on the dependency files returned by the scanner.
When this flag is not set,
the Node subsystem will
only invoke the scanner on the file being scanned,
and not (for example) also on the files
specified by the #include lines
in the file being scanned.
recursive
may be a callable function,
in which case it will be called with a list of
Nodes found and
should return a list of Nodes
that should be scanned recursively;
this can be used to select a specific subset of
Nodes for additional scanning.
Note that scons has a global SourceFileScanner object that is used by the Object(), SharedObject(), and StaticObject() builders to decide which scanner should be used for different file extensions. You can using the SourceFileScanner.add_scanner() method to add your own Scanner object to the scons infrastructure that builds target programs or libraries from a list of source files of different types:
-
def xyz_scan(node, env, path): contents = node.get_text_contents() # Scan the contents and return the included files. XYZScanner = Scanner(xyz_scan) SourceFileScanner.add_scanner('.xyx', XYZScanner) env.Program('my_prog', ['file1.c', 'file2.f', 'file3.xyz'])
-
SYSTEM-SPECIFIC BEHAVIOR
SCons and its configuration files are very portable, due largely to its implementation in Python. There are, however, a few portability issues waiting to trap the unwary..C file suffix
SCons handles the upper-case .C file suffix differently, depending on the capabilities of the underlying system. On a case-sensitive system such as Linux or UNIX, SCons treats a file with a .C suffix as a C++ source file. On a case-insensitive system such as Windows, SCons treats a file with a .C suffix as a C source file..F file suffix
SCons handles the upper-case .F file suffix differently, depending on the capabilities of the underlying system. On a case-sensitive system such as Linux or UNIX, SCons treats a file with a .F suffix as a Fortran source file that is to be first run through the standard C preprocessor. On a case-insensitive system such as Windows, SCons treats a file with a .F suffix as a Fortran source file that should not be run through the C preprocessor.Windows: Cygwin Tools and Cygwin Python vs. Windows Pythons
Cygwin supplies a set of tools and utilities that let users work on a Windows system using a more POSIX-like environment. The Cygwin tools, including Cygwin Python, do this, in part, by sharing an ability to interpret UNIX-like path names. For example, the Cygwin tools will internally translate a Cygwin path name like /cygdrive/c/mydir to an equivalent Windows pathname of C:/mydir (equivalent to C:\mydir).Versions of Python that are built for native Windows execution, such as the python.org and ActiveState versions, do not have the Cygwin path name semantics. This means that using a native Windows version of Python to build compiled programs using Cygwin tools (such as gcc, bison, and flex) may yield unpredictable results. "Mixing and matching" in this way can be made to work, but it requires careful attention to the use of path names in your SConscript files.
In practice, users can sidestep the issue by adopting the following rules: When using gcc, use the Cygwin-supplied Python interpreter to run SCons; when using Microsoft Visual C/C++ (or some other Windows compiler) use the python.org or ActiveState version of Python to run SCons.
Windows: scons.bat file
On Windows systems, SCons is executed via a wrapper scons.bat file. This has (at least) two ramifications:First, Windows command-line users that want to use variable assignment on the command line may have to put double quotes around the assignments:
-
scons "FOO=BAR" "BAZ=BLEH"
Second, the Cygwin shell does not recognize this file as being the same as an scons command issued at the command-line prompt. You can work around this either by executing scons.bat from the Cygwin command line, or by creating a wrapper shell script named scons .
MinGW
The MinGW bin directory must be in your PATH environment variable or the PATH variable under the ENV construction variable for SCons to detect and use the MinGW tools. When running under the native Windows Python interpreter, SCons will prefer the MinGW tools over the Cygwin tools, if they are both installed, regardless of the order of the bin directories in the PATH variable. If you have both MSVC and MinGW installed and you want to use MinGW instead of MSVC, then you must explictly tell SCons to use MinGW by passing
-
tools=['mingw']
to the Environment() function, because SCons will prefer the MSVC tools over the MinGW tools.
EXAMPLES
To help you get started using SCons, this section contains a brief overview of some common tasks.
Basic Compilation From a Single Source File
-
env = Environment() env.Program(target = 'foo', source = 'foo.c')
Note: Build the file by specifying the target as an argument ("scons foo" or "scons foo.exe"). or by specifying a dot ("scons .").
Basic Compilation From Multiple Source Files
-
env = Environment() env.Program(target = 'foo', source = Split('f1.c f2.c f3.c'))
Setting a Compilation Flag
-
env = Environment(CCFLAGS = '-g') env.Program(target = 'foo', source = 'foo.c')
Search The Local Directory For .h Files
Note: You do not need to set CCFLAGS to specify -I options by hand. SCons will construct the right -I options from CPPPATH.
-
env = Environment(CPPPATH = ['.']) env.Program(target = 'foo', source = 'foo.c')
Search Multiple Directories For .h Files
-
env = Environment(CPPPATH = ['include1', 'include2']) env.Program(target = 'foo', source = 'foo.c')
Building a Static Library
-
env = Environment() env.StaticLibrary(target = 'foo', source = Split('l1.c l2.c')) env.StaticLibrary(target = 'bar', source = ['l3.c', 'l4.c'])
Building a Shared Library
-
env = Environment() env.SharedLibrary(target = 'foo', source = ['l5.c', 'l6.c']) env.SharedLibrary(target = 'bar', source = Split('l7.c l8.c'))
Linking a Local Library Into a Program
-
env = Environment(LIBS = 'mylib', LIBPATH = ['.']) env.Library(target = 'mylib', source = Split('l1.c l2.c')) env.Program(target = 'prog', source = ['p1.c', 'p2.c'])
Defining Your Own Builder Object
Notice that when you invoke the Builder, you can leave off the target file suffix, and SCons will add it automatically.
-
bld = Builder(action = 'pdftex < $SOURCES > $TARGET' suffix = '.pdf', src_suffix = '.tex') env = Environment(BUILDERS = {'PDFBuilder' : bld}) env.PDFBuilder(target = 'foo.pdf', source = 'foo.tex') # The following creates "bar.pdf" from "bar.tex" env.PDFBuilder(target = 'bar', source = 'bar')
Note also that the above initialization overwrites the default Builder objects, so the Environment created above can not be used call Builders like env.Program(), env.Object(), env.StaticLibrary(), etc.
Adding Your Own Builder Object to an Environment
-
bld = Builder(action = 'pdftex < $SOURCES > $TARGET' suffix = '.pdf', src_suffix = '.tex') env = Environment() env.Append(BUILDERS = {'PDFBuilder' : bld}) env.PDFBuilder(target = 'foo.pdf', source = 'foo.tex') env.Program(target = 'bar', source = 'bar.c')
You also can use other Pythonic techniques to add to the BUILDERS construction variable, such as:
-
env = Environment() env['BUILDERS]['PDFBuilder'] = bld
Defining Your Own Scanner Object
The following example shows an extremely simple scanner (the kfile_scan() function) that doesn't use a search path at all and simply returns the file names present on any include lines in the scanned file. This would implicitly assume that all included files live in the top-level directory:
-
import re include_re = re.compile(r'^include\s+(\S+)$', re.M) def kfile_scan(node, env, path, arg): contents = node.get_text_contents() includes = include_re.findall(contents) return includes kscan = Scanner(name = 'kfile', function = kfile_scan, argument = None, skeys = ['.k']) scanners = Environment().Dictionary('SCANNERS') env = Environment(SCANNERS = scanners + [kscan]) env.Command('foo', 'foo.k', 'kprocess < $SOURCES > $TARGET') bar_in = File('bar.in') env.Command('bar', bar_in, 'kprocess $SOURCES > $TARGET') bar_in.target_scanner = kscan
Here is a similar but more complete example that searches a path of directories (specified as the MYPATH construction variable) for files that actually exist:
-
include_re = re.compile(r'^include\s+(\S+)$', re.M) def my_scan(node, env, path, arg): contents = node.get_text_contents() includes = include_re.findall(contents) if includes == []: return [] results = [] for inc in includes: for dir in path: file = dir + os.sep + inc if os.path.exists(file): results.append(file) break return results scanner = Scanner(name = 'myscanner', function = my_scan, argument = None, skeys = ['.x'], path_function = FindPathDirs('MYPATH'), ) scanners = Environment().Dictionary('SCANNERS') env = Environment(SCANNERS = scanners + [scanner])
The FindPathDirs() function used in the previous example returns a function (actually a callable Python object) that will return a list of directories specified in the $MYPATH construction variable. If you need to customize how the search path is derived, you would provide your own path_function argument when creating the Scanner object, as follows:
-
# MYPATH is a list of directories to search for files in def pf(env, dir, target, source, arg): top_dir = Dir('#').abspath results = [] if 'MYPATH' in env: for p in env['MYPATH']: results.append(top_dir + os.sep + p) return results scanner = Scanner(name = 'myscanner', function = my_scan, argument = None, skeys = ['.x'], path_function = pf, )
Creating a Hierarchical Build
Notice that the file names specified in a subdirectory's SConscript file are relative to that subdirectory.
-
SConstruct: env = Environment() env.Program(target = 'foo', source = 'foo.c') SConscript('sub/SConscript') sub/SConscript: env = Environment() # Builds sub/foo from sub/foo.c env.Program(target = 'foo', source = 'foo.c') SConscript('dir/SConscript') sub/dir/SConscript: env = Environment() # Builds sub/dir/foo from sub/dir/foo.c env.Program(target = 'foo', source = 'foo.c')
Sharing Variables Between SConscript Files
You must explicitly Export() and Import() variables that you want to share between SConscript files.
-
SConstruct: env = Environment() env.Program(target = 'foo', source = 'foo.c') Export("env") SConscript('subdirectory/SConscript') subdirectory/SConscript: Import("env") env.Program(target = 'foo', source = 'foo.c')
Building Multiple Variants From the Same Source
Use the variant_dir keyword argument to the SConscript function to establish one or more separate variant build directory trees for a given source directory:
-
SConstruct: cppdefines = ['FOO'] Export("cppdefines") SConscript('src/SConscript', variant_dir='foo') cppdefines = ['BAR'] Export("cppdefines") SConscript('src/SConscript', variant_dir='bar') src/SConscript: Import("cppdefines") env = Environment(CPPDEFINES = cppdefines) env.Program(target = 'src', source = 'src.c')
Note the use of the Export() method to set the "cppdefines" variable to a different value each time we call the SConscript function.
Hierarchical Build of Two Libraries Linked With a Program
-
SConstruct: env = Environment(LIBPATH = ['#libA', '#libB']) Export('env') SConscript('libA/SConscript') SConscript('libB/SConscript') SConscript('Main/SConscript') libA/SConscript: Import('env') env.Library('a', Split('a1.c a2.c a3.c')) libB/SConscript: Import('env') env.Library('b', Split('b1.c b2.c b3.c')) Main/SConscript: Import('env') e = env.Copy(LIBS = ['a', 'b']) e.Program('foo', Split('m1.c m2.c m3.c'))
The '#' in the LIBPATH directories specify that they're relative to the top-level directory, so they don't turn into "Main/libA" when they're used in Main/SConscript.
Specifying only 'a' and 'b' for the library names allows SCons to append the appropriate library prefix and suffix for the current platform (for example, 'liba.a' on POSIX systems, 'a.lib' on Windows).
Customizing construction variables from the command line.
The following would allow the C compiler to be specified on the command line or in the file custom.py.
-
vars = Variables('custom.py') vars.Add('CC', 'The C compiler.') env = Environment(variables=vars) Help(vars.GenerateHelpText(env))
The user could specify the C compiler on the command line:
-
scons "CC=my_cc"
or in the custom.py file:
-
CC = 'my_cc'
or get documentation on the options:
-
$ scons -h CC: The C compiler. default: None actual: cc
Using Microsoft Visual C++ precompiled headers
Since windows.h includes everything and the kitchen sink, it can take quite some time to compile it over and over again for a bunch of object files, so Microsoft provides a mechanism to compile a set of headers once and then include the previously compiled headers in any object file. This technology is called precompiled headers. The general recipe is to create a file named "StdAfx.cpp" that includes a single header named "StdAfx.h", and then include every header you want to precompile in "StdAfx.h", and finally include "StdAfx.h" as the first header in all the source files you are compiling to object files. For example:
StdAfx.h:
-
#include <windows.h> #include <my_big_header.h>
StdAfx.cpp:
-
#include <StdAfx.h>
Foo.cpp:
-
#include <StdAfx.h> /* do some stuff */
Bar.cpp:
-
#include <StdAfx.h> /* do some other stuff */
SConstruct:
-
env=Environment() env['PCHSTOP'] = 'StdAfx.h' env['PCH'] = env.PCH('StdAfx.cpp')[0] env.Program('MyApp', ['Foo.cpp', 'Bar.cpp'])
For more information see the document for the PCH builder, and the PCH and PCHSTOP construction variables. To learn about the details of precompiled headers consult the MSDN documention for /Yc, /Yu, and /Yp.
Using Microsoft Visual C++ external debugging information
Since including debugging information in programs and shared libraries can cause their size to increase significantly, Microsoft provides a mechanism for including the debugging information in an external file called a PDB file. SCons supports PDB files through the PDB construction variable.
SConstruct:
-
env=Environment() env['PDB'] = 'MyApp.pdb' env.Program('MyApp', ['Foo.cpp', 'Bar.cpp'])
For more information see the document for the PDB construction variable.
ENVIRONMENT
- SCONS_LIB_DIR
-
Specifies the directory that contains the SCons Python module directory
(e.g. /home/aroach/scons-src-0.01/src/engine).
- SCONSFLAGS
-
A string of options that will be used by scons in addition to those passed
on the command line.
SEE ALSO
scons User Manual, scons Design Document, scons source code.AUTHORS
Steven Knight <knight@baldmt.com>Anthony Roach <aroach@electriceyeball.com>
Index
- NAME
- SYNOPSIS
- DESCRIPTION
- OPTIONS
- CONFIGURATION FILE REFERENCE
- EXTENDING SCONS
- SYSTEM-SPECIFIC BEHAVIOR
- EXAMPLES
-
- Basic Compilation From a Single Source File
- Basic Compilation From Multiple Source Files
- Setting a Compilation Flag
- Search The Local Directory For .h Files
- Search Multiple Directories For .h Files
- Building a Static Library
- Building a Shared Library
- Linking a Local Library Into a Program
- Defining Your Own Builder Object
- Adding Your Own Builder Object to an Environment
- Defining Your Own Scanner Object
- Creating a Hierarchical Build
- Sharing Variables Between SConscript Files
- Building Multiple Variants From the Same Source
- Hierarchical Build of Two Libraries Linked With a Program
- Customizing construction variables from the command line.
- Using Microsoft Visual C++ precompiled headers
- Using Microsoft Visual C++ external debugging information
- ENVIRONMENT
- SEE ALSO
- AUTHORS
This document was created by man2html using the manual pages.
Time: 17:32:41 GMT, May 11, 2012
