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display file or file system status



Manpage of STAT


Section: User Commands (1)
Updated: October 2011
Index Return to Main Contents


stat - display file or file system status  


stat [OPTION]... FILE...  


Display file or file system status.

-L, --dereference
follow links
-f, --file-system
display file system status instead of file status
-c --format=FORMAT
use the specified FORMAT instead of the default; output a newline after each use of FORMAT
like --format, but interpret backslash escapes, and do not output a mandatory trailing newline. If you want a newline, include
-t, --terse
print the information in terse form
display this help and exit
output version information and exit

The valid format sequences for files (without --file-system):

Access rights in octal
Access rights in human readable form
Number of blocks allocated (see %B)
The size in bytes of each block reported by %b
SELinux security context string
Device number in decimal
Device number in hex
Raw mode in hex
File type
Group ID of owner
Group name of owner
Number of hard links
Inode number
Mount point
File name
Quoted file name with dereference if symbolic link
I/O block size
Total size, in bytes
Major device type in hex
Minor device type in hex
User ID of owner
User name of owner
Time of file birth, human-readable; - if unknown
Time of file birth, seconds since Epoch; 0 if unknown
Time of last access, human-readable
Time of last access, seconds since Epoch
Time of last modification, human-readable
Time of last modification, seconds since Epoch
Time of last change, human-readable
Time of last change, seconds since Epoch

Valid format sequences for file systems:

Free blocks available to non-superuser
Total data blocks in file system
Total file nodes in file system
Free file nodes in file system
Free blocks in file system
File System ID in hex
Maximum length of filenames
File name
Block size (for faster transfers)
Fundamental block size (for block counts)
Type in hex
Type in human readable form

NOTE: your shell may have its own version of stat, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports.  


Written by Michael Meskes.  


Report stat bugs to
GNU coreutils home page: <>
General help using GNU software: <>
Report stat translation bugs to <>  


Copyright © 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.  



The full documentation for stat is maintained as a Texinfo manual. If the info and stat programs are properly installed at your site, the command

info coreutils aqstat invocationaq

should give you access to the complete manual.




This document was created by man2html using the manual pages.
Time: 17:32:36 GMT, October 23, 2013


Manpage of STAT


Section: Linux Programmer's Manual (2)
Updated: 2010-12-03
Index Return to Main Contents


stat, fstat, lstat - get file status  


#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

int stat(const char *path, struct stat *buf);
int fstat(int fd, struct stat *buf);
int lstat(const char *path, struct stat *buf);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):


|| /* Since glibc 2.10: */ _POSIX_C_SOURCE >= 200112L


These functions return information about a file. No permissions are required on the file itself, but --- in the case of stat() and lstat() --- execute (search) permission is required on all of the directories in path that lead to the file.

stat() stats the file pointed to by path and fills in buf.

lstat() is identical to stat(), except that if path is a symbolic link, then the link itself is stat-ed, not the file that it refers to.

fstat() is identical to stat(), except that the file to be stat-ed is specified by the file descriptor fd.

All of these system calls return a stat structure, which contains the following fields:

struct stat {
    dev_t     st_dev;     /* ID of device containing file */
    ino_t     st_ino;     /* inode number */
    mode_t    st_mode;    /* protection */
    nlink_t   st_nlink;   /* number of hard links */
    uid_t     st_uid;     /* user ID of owner */
    gid_t     st_gid;     /* group ID of owner */
    dev_t     st_rdev;    /* device ID (if special file) */
    off_t     st_size;    /* total size, in bytes */
    blksize_t st_blksize; /* blocksize for file system I/O */
    blkcnt_t  st_blocks;  /* number of 512B blocks allocated */
    time_t    st_atime;   /* time of last access */
    time_t    st_mtime;   /* time of last modification */
    time_t    st_ctime;   /* time of last status change */

The st_dev field describes the device on which this file resides. (The major(3) and minor(3) macros may be useful to decompose the device ID in this field.)

The st_rdev field describes the device that this file (inode) represents.

The st_size field gives the size of the file (if it is a regular file or a symbolic link) in bytes. The size of a symlink is the length of the pathname it contains, without a trailing null byte.

The st_blocks field indicates the number of blocks allocated to the file, 512-byte units. (This may be smaller than st_size/512 when the file has holes.)

The st_blksize field gives the "preferred" blocksize for efficient file system I/O. (Writing to a file in smaller chunks may cause an inefficient read-modify-rewrite.)

Not all of the Linux file systems implement all of the time fields. Some file system types allow mounting in such a way that file and/or directory accesses do not cause an update of the st_atime field. (See noatime, nodiratime, and relatime in mount(8), and related information in mount(2).) In addition, st_atime is not updated if a file is opened with the O_NOATIME; see open(2).

The field st_atime is changed by file accesses, for example, by execve(2), mknod(2), pipe(2), utime(2) and read(2) (of more than zero bytes). Other routines, like mmap(2), may or may not update st_atime.

The field st_mtime is changed by file modifications, for example, by mknod(2), truncate(2), utime(2) and write(2) (of more than zero bytes). Moreover, st_mtime of a directory is changed by the creation or deletion of files in that directory. The st_mtime field is not changed for changes in owner, group, hard link count, or mode.

The field st_ctime is changed by writing or by setting inode information (i.e., owner, group, link count, mode, etc.).

The following POSIX macros are defined to check the file type using the st_mode field:

is it a regular file?
character device?
block device?
FIFO (named pipe)?
symbolic link? (Not in POSIX.1-1996.)
socket? (Not in POSIX.1-1996.)

The following flags are defined for the st_mode field:

S_IFMT0170000bit mask for the file type bit fields
S_IFLNK0120000symbolic link
S_IFREG0100000regular file
S_IFBLK0060000block device
S_IFCHR0020000character device
S_ISUID0004000set UID bit
S_ISGID0002000set-group-ID bit (see below)
S_ISVTX0001000sticky bit (see below)
S_IRWXU00700mask for file owner permissions
S_IRUSR00400owner has read permission
S_IWUSR00200owner has write permission
S_IXUSR00100owner has execute permission
S_IRWXG00070mask for group permissions
S_IRGRP00040group has read permission
S_IWGRP00020group has write permission
S_IXGRP00010group has execute permission
S_IRWXO00007mask for permissions for others (not in group)
S_IROTH00004others have read permission
S_IWOTH00002others have write permission
S_IXOTH00001others have execute permission
The set-group-ID bit (S_ISGID) has several special uses. For a directory it indicates that BSD semantics is to be used for that directory: files created there inherit their group ID from the directory, not from the effective group ID of the creating process, and directories created there will also get the S_ISGID bit set. For a file that does not have the group execution bit (S_IXGRP) set, the set-group-ID bit indicates mandatory file/record locking. The sticky bit (S_ISVTX) on a directory means that a file in that directory can be renamed or deleted only by the owner of the file, by the owner of the directory, and by a privileged process.  


On success, zero is returned. On error, -1 is returned, and errno is set appropriately.  


Search permission is denied for one of the directories in the path prefix of path. (See also path_resolution(7).)
fd is bad.
Bad address.
Too many symbolic links encountered while traversing the path.
File name too long.
A component of path does not exist, or path is an empty string.
Out of memory (i.e., kernel memory).
A component of the path prefix of path is not a directory.
(stat()) path refers to a file whose size cannot be represented in the type off_t. This can occur when an application compiled on a 32-bit platform without -D_FILE_OFFSET_BITS=64 calls stat() on a file whose size exceeds (1<<31)-1 bits.


These system calls conform to SVr4, 4.3BSD, POSIX.1-2001.

Use of the st_blocks and st_blksize fields may be less portable. (They were introduced in BSD. The interpretation differs between systems, and possibly on a single system when NFS mounts are involved.) If you need to obtain the definition of the blkcnt_t or blksize_t types from <sys/stat.h>, then define _XOPEN_SOURCE with the value 500 or greater (before including any header files).

POSIX does not describe the S_IFMT, S_IFSOCK, S_IFLNK, S_IFREG, S_IFBLK, S_IFDIR, S_IFCHR, S_IFIFO, S_ISVTX bits, but instead demands the use of the macros S_ISDIR(), etc. The S_ISLNK() and S_ISSOCK() macros are not in POSIX.1-1996, but both are present in POSIX.1-2001; the former is from SVID 4, the latter from SUSv2.

UNIX V7 (and later systems) had S_IREAD, S_IWRITE, S_IEXEC, where POSIX prescribes the synonyms S_IRUSR, S_IWUSR, S_IXUSR.  

Other Systems

Values that have been (or are) in use on various systems:
f000S_IFMT170000mask for file type
0000000000SCO out-of-service inode; BSD unknown
type; SVID-v2 and XPG2 have both
0 and 0100000 for ordinary file
1000S_IFIFOp|010000FIFO (named pipe)
2000S_IFCHRc020000character special (V7)
3000S_IFMPC030000multiplexed character special (V7)
4000S_IFDIRd/040000directory (V7)
5000S_IFNAM050000XENIX named special file
with two subtypes, distinguished by
st_rdev values 1, 2
0001S_INSEMs000001XENIX semaphore subtype of IFNAM
0002S_INSHDm000002XENIX shared data subtype of IFNAM
6000S_IFBLKb060000block special (V7)
7000S_IFMPB070000multiplexed block special (V7)
8000S_IFREG-100000regular (V7)
9000S_IFCMP110000VxFS compressed
9000S_IFNWKn110000network special (HP-UX)
a000S_IFLNKl@120000symbolic link (BSD)
b000S_IFSHAD130000Solaris shadow inode for ACL
(not seen by userspace)
c000S_IFSOCKs=140000socket (BSD; also "S_IFSOC" on VxFS)
d000S_IFDOORD>150000Solaris door
e000S_IFWHTw%160000BSD whiteout (not used for inode)
0200S_ISVTX001000sticky bit: save swapped text even
after use (V7)
reserved (SVID-v2)
On nondirectories: don't cache this
file (SunOS)
On directories: restricted deletion
flag (SVID-v4.2)
0400S_ISGID002000set-group-ID on execution (V7)
for directories: use BSD semantics for
propagation of GID
0400S_ENFMT002000System V file locking enforcement (shared
with S_ISGID)
0800S_ISUID004000set-user-ID on execution (V7)
0800S_CDF004000directory is a context dependent
file (HP-UX)

A sticky command appeared in Version 32V AT&T UNIX.  


Since kernel 2.5.48, the stat structure supports nanosecond resolution for the three file timestamp fields. Glibc exposes the nanosecond component of each field using names of the form st_atim.tv_nsec if the _BSD_SOURCE or _SVID_SOURCE feature test macro is defined. These fields are specified in POSIX.1-2008, and, starting with version 2.12, glibc also exposes these field names if _POSIX_C_SOURCE is defined with the value 200809L or greater, or _XOPEN_SOURCE is defined with the value 700 or greater. If none of the aforementioned macros are defined, then the nanosecond values are exposed with names of the form st_atimensec. On file systems that do not support subsecond timestamps, the nanosecond fields are returned with the value 0.

On Linux, lstat() will generally not trigger automounter action, whereas stat() will.

For most files under the /proc directory, stat() does not return the file size in the st_size field; instead the field is returned with the value 0.  

Underlying kernel interface

Over time, increases in the size of the stat structure have led to three successive versions of stat(): sys_stat() (slot __NR_oldstat), sys_newstat() (slot __NR_stat), and sys_stat64() (new in kernel 2.4; slot __NR_stat64). The glibc stat() wrapper function hides these details from applications, invoking the most recent version of the system call provided by the kernel, and repacking the returned information if required for old binaries. Similar remarks apply for fstat() and lstat().  


The following program calls stat() and displays selected fields in the returned stat structure.

#include <sys/types.h>
#include <sys/stat.h>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>

main(int argc, char *argv[])
    struct stat sb;

    if (argc != 2) {
        fprintf(stderr, "Usage: %s <pathname>
", argv[0]); exit(EXIT_FAILURE); } if (stat(argv[1], &sb) == -1) { perror("stat"); exit(EXIT_FAILURE); } printf("File type: "); switch (sb.st_mode & S_IFMT) { case S_IFBLK: printf("block device
"); break; case S_IFCHR: printf("character device
"); break; case S_IFDIR: printf("directory
"); break; case S_IFIFO: printf("FIFO/pipe
"); break; case S_IFLNK: printf("symlink
"); break; case S_IFREG: printf("regular file
"); break; case S_IFSOCK: printf("socket
"); break; default: printf("unknown?
"); break; } printf("I-node number: %ld
", (long) sb.st_ino); printf("Mode: %lo (octal)
", (unsigned long) sb.st_mode); printf("Link count: %ld
", (long) sb.st_nlink); printf("Ownership: UID=%ld GID=%ld
", (long) sb.st_uid, (long) sb.st_gid); printf("Preferred I/O block size: %ld bytes
", (long) sb.st_blksize); printf("File size: %lld bytes
", (long long) sb.st_size); printf("Blocks allocated: %lld
", (long long) sb.st_blocks); printf("Last status change: %s", ctime(&sb.st_ctime)); printf("Last file access: %s", ctime(&sb.st_atime)); printf("Last file modification: %s", ctime(&sb.st_mtime)); exit(EXIT_SUCCESS); }


access(2), chmod(2), chown(2), fstatat(2), readlink(2), utime(2), capabilities(7), symlink(7)  


This page is part of release 3.32 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at



Other Systems
Underlying kernel interface

This document was created by man2html using the manual pages.
Time: 17:32:36 GMT, October 23, 2013


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