term% cat index.txt STAT(2) System Calls Manual STAT(2)
NAME
stat, lstat, fstat - get file status
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
stat(name, buf)
char *name;
struct stat *buf;
lstat(name, buf)
char *name;
struct stat *buf;
fstat(fildes, buf)
struct stat *buf;
DESCRIPTION
Stat obtains detailed information about a named file. Lstat obtains
the same information, but in the case of a symbolic link (see link(2)),
supplies information about the link itself. Fstat obtains the same in‐
formation about an open file known by a file descriptor.
Name points to a null-terminated string naming a file; buf is the ad‐
dress of a buffer into which information is placed concerning the file.
It is unnecessary to have any permissions at all with respect to the
file, but all directories leading to the file must be searchable. The
layout of the structure pointed to by buf is given below; st_mode is
encoded according to the `#define' statements.
/* Copyright (C) 1991-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/*
* POSIX Standard: 5.6 File Characteristics <sys/stat.h>
*/
#ifndef _SYS_STAT_H
#define _SYS_STAT_H 1
#include <features.h>
#include <bits/types.h> /* For __mode_t and __dev_t. */
#ifdef __USE_XOPEN2K8
# include <bits/types/struct_timespec.h>
#endif
#if defined __USE_XOPEN || defined __USE_XOPEN2K
/* The Single Unix specification says that some more types are
available here. */
# include <bits/types/time_t.h>
# ifndef __dev_t_defined
typedef __dev_t dev_t;
# define __dev_t_defined
# endif
# ifndef __gid_t_defined
typedef __gid_t gid_t;
# define __gid_t_defined
# endif
# ifndef __ino_t_defined
# ifndef __USE_FILE_OFFSET64
typedef __ino_t ino_t;
# else
typedef __ino64_t ino_t;
# endif
# define __ino_t_defined
# endif
# ifndef __mode_t_defined
typedef __mode_t mode_t;
# define __mode_t_defined
# endif
# ifndef __nlink_t_defined
typedef __nlink_t nlink_t;
# define __nlink_t_defined
# endif
# ifndef __off_t_defined
# ifndef __USE_FILE_OFFSET64
typedef __off_t off_t;
# else
typedef __off64_t off_t;
# endif
# define __off_t_defined
# endif
# ifndef __uid_t_defined
typedef __uid_t uid_t;
# define __uid_t_defined
# endif
#endif /* X/Open */
#ifdef __USE_UNIX98
# ifndef __blkcnt_t_defined
# ifndef __USE_FILE_OFFSET64
typedef __blkcnt_t blkcnt_t;
# else
typedef __blkcnt64_t blkcnt_t;
# endif
# define __blkcnt_t_defined
# endif
# ifndef __blksize_t_defined
typedef __blksize_t blksize_t;
# define __blksize_t_defined
# endif
#endif /* Unix98 */
__BEGIN_DECLS
#include <bits/stat.h>
#if defined __USE_MISC || defined __USE_XOPEN
# define S_IFMT __S_IFMT
# define S_IFDIR __S_IFDIR
# define S_IFCHR __S_IFCHR
# define S_IFBLK __S_IFBLK
# define S_IFREG __S_IFREG
# ifdef __S_IFIFO
# define S_IFIFO __S_IFIFO
# endif
# ifdef __S_IFLNK
# define S_IFLNK __S_IFLNK
# endif
# if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && defined __S_IFSOCK
# define S_IFSOCK __S_IFSOCK
# endif
#endif
/* Test macros for file types. */
#define __S_ISTYPE(mode, mask) (((mode) & __S_IFMT) == (mask))
#define S_ISDIR(mode) __S_ISTYPE((mode), __S_IFDIR)
#define S_ISCHR(mode) __S_ISTYPE((mode), __S_IFCHR)
#define S_ISBLK(mode) __S_ISTYPE((mode), __S_IFBLK)
#define S_ISREG(mode) __S_ISTYPE((mode), __S_IFREG)
#ifdef __S_IFIFO
# define S_ISFIFO(mode) __S_ISTYPE((mode), __S_IFIFO)
#endif
#ifdef __S_IFLNK
# define S_ISLNK(mode) __S_ISTYPE((mode), __S_IFLNK)
#endif
#if defined __USE_MISC && !defined __S_IFLNK
# define S_ISLNK(mode) 0
#endif
#if (defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K) && defined __S_IFSOCK
# define S_ISSOCK(mode) __S_ISTYPE((mode), __S_IFSOCK)
#elif defined __USE_XOPEN2K
# define S_ISSOCK(mode) 0
#endif
/* These are from POSIX.1b. If the objects are not implemented using separate
distinct file types, the macros always will evaluate to zero. Unlike the
other S_* macros the following three take a pointer to a `struct stat'
object as the argument. */
#ifdef __USE_POSIX199309
# define S_TYPEISMQ(buf) __S_TYPEISMQ(buf)
# define S_TYPEISSEM(buf) __S_TYPEISSEM(buf)
# define S_TYPEISSHM(buf) __S_TYPEISSHM(buf)
#endif
/* Protection bits. */
#define S_ISUID __S_ISUID /* Set user ID on execution. */
#define S_ISGID __S_ISGID /* Set group ID on execution. */
#if defined __USE_MISC || defined __USE_XOPEN
/* Save swapped text after use (sticky bit). This is pretty well obsolete. */
# define S_ISVTX __S_ISVTX
#endif
#define S_IRUSR __S_IREAD /* Read by owner. */
#define S_IWUSR __S_IWRITE /* Write by owner. */
#define S_IXUSR __S_IEXEC /* Execute by owner. */
/* Read, write, and execute by owner. */
#define S_IRWXU (__S_IREAD|__S_IWRITE|__S_IEXEC)
#ifdef __USE_MISC
# define S_IREAD S_IRUSR
# define S_IWRITE S_IWUSR
# define S_IEXEC S_IXUSR
#endif
#define S_IRGRP (S_IRUSR >> 3) /* Read by group. */
#define S_IWGRP (S_IWUSR >> 3) /* Write by group. */
#define S_IXGRP (S_IXUSR >> 3) /* Execute by group. */
/* Read, write, and execute by group. */
#define S_IRWXG (S_IRWXU >> 3)
#define S_IROTH (S_IRGRP >> 3) /* Read by others. */
#define S_IWOTH (S_IWGRP >> 3) /* Write by others. */
#define S_IXOTH (S_IXGRP >> 3) /* Execute by others. */
/* Read, write, and execute by others. */
#define S_IRWXO (S_IRWXG >> 3)
#ifdef __USE_MISC
/* Macros for common mode bit masks. */
# define ACCESSPERMS (S_IRWXU|S_IRWXG|S_IRWXO) /* 0777 */
# define ALLPERMS (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO)/* 07777 */
# define DEFFILEMODE (S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)/* 0666*/
# define S_BLKSIZE 512 /* Block size for `st_blocks'. */
#endif
#ifndef __USE_FILE_OFFSET64
/* Get file attributes for FILE and put them in BUF. */
extern int stat (const char *__restrict __file,
struct stat *__restrict __buf) __THROW __nonnull ((1, 2));
/* Get file attributes for the file, device, pipe, or socket
that file descriptor FD is open on and put them in BUF. */
extern int fstat (int __fd, struct stat *__buf) __THROW __nonnull ((2));
#else
# ifdef __USE_TIME_BITS64
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (stat, (const char *__restrict __file,
struct stat *__restrict __buf),
__stat64_time64)
__nonnull ((1, 2));
extern int __REDIRECT_NTH (fstat, (int __fd, struct stat *__buf),
__fstat64_time64)
__nonnull ((2));
# else
# define stat __stat64_time64
# define fstat __fstat64_time64
# endif
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (stat, (const char *__restrict __file,
struct stat *__restrict __buf), stat64)
__nonnull ((1, 2));
extern int __REDIRECT_NTH (fstat, (int __fd, struct stat *__buf), fstat64)
__nonnull ((2));
# else
# define stat stat64
# define fstat fstat64
# endif
# endif
#endif
#ifdef __USE_LARGEFILE64
# ifndef __USE_TIME_BITS64
extern int stat64 (const char *__restrict __file,
struct stat64 *__restrict __buf) __THROW __nonnull ((1, 2));
extern int fstat64 (int __fd, struct stat64 *__buf) __THROW __nonnull ((2));
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (stat64, (const char *__restrict __file,
struct stat64 *__restrict __buf),
__stat64_time64)
__nonnull ((1, 2));
extern int __REDIRECT_NTH (fstat64, (int __fd, struct stat64 *__buf),
__fstat64_time64)
__nonnull ((2));
# else
# define stat64 __stat64_time64
# define fstat64 __fstat64_time
# endif
# endif
#endif
#ifdef __USE_ATFILE
/* Similar to stat, get the attributes for FILE and put them in BUF.
Relative path names are interpreted relative to FD unless FD is
AT_FDCWD. */
# ifndef __USE_FILE_OFFSET64
extern int fstatat (int __fd, const char *__restrict __file,
struct stat *__restrict __buf, int __flag)
__THROW __nonnull ((2, 3));
# else
# ifdef __USE_TIME_BITS64
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (fstatat, (int __fd, const char *__restrict __file,
struct stat *__restrict __buf,
int __flag),
__fstatat64_time64) __nonnull ((2, 3));
# else
# define fstatat __fstatat64_time64
# endif
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (fstatat, (int __fd, const char *__restrict __file,
struct stat *__restrict __buf,
int __flag),
fstatat64) __nonnull ((2, 3));
# else
# define fstatat fstatat64
# endif
# endif
# endif
# ifdef __USE_LARGEFILE64
# ifndef __USE_TIME_BITS64
extern int fstatat64 (int __fd, const char *__restrict __file,
struct stat64 *__restrict __buf, int __flag)
__THROW __nonnull ((2, 3));
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (fstatat64, (int __fd,
const char *__restrict __file,
struct stat64 *__restrict __buf,
int __flag),
__fstatat64_time64)
__nonnull ((2, 3));
# else
# define fstatat64 __fstatat64_time64
# endif
# endif
# endif
#endif
#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
# ifndef __USE_FILE_OFFSET64
/* Get file attributes about FILE and put them in BUF.
If FILE is a symbolic link, do not follow it. */
extern int lstat (const char *__restrict __file,
struct stat *__restrict __buf) __THROW __nonnull ((1, 2));
# else
# ifdef __USE_TIME_BITS64
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (lstat,
(const char *__restrict __file,
struct stat *__restrict __buf), __lstat64_time64)
__nonnull ((1, 2));
# else
# define lstat __lstat64_time64
# endif
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (lstat,
(const char *__restrict __file,
struct stat *__restrict __buf), lstat64)
__nonnull ((1, 2));
# else
# define lstat lstat64
# endif
# endif
# endif
# ifdef __USE_LARGEFILE64
# ifndef __USE_TIME_BITS64
extern int lstat64 (const char *__restrict __file,
struct stat64 *__restrict __buf)
__THROW __nonnull ((1, 2));
# else
extern int __REDIRECT_NTH (lstat64, (const char *__restrict __file,
struct stat64 *__restrict __buf),
__lstat64_time64)
__nonnull ((1, 2));
# endif
# endif
#endif
/* Set file access permissions for FILE to MODE.
If FILE is a symbolic link, this affects its target instead. */
extern int chmod (const char *__file, __mode_t __mode)
__THROW __nonnull ((1));
#ifdef __USE_MISC
/* Set file access permissions for FILE to MODE.
If FILE is a symbolic link, this affects the link itself
rather than its target. */
extern int lchmod (const char *__file, __mode_t __mode)
__THROW __nonnull ((1));
#endif
/* Set file access permissions of the file FD is open on to MODE. */
#if defined __USE_POSIX199309 || defined __USE_XOPEN_EXTENDED
extern int fchmod (int __fd, __mode_t __mode) __THROW;
#endif
#ifdef __USE_ATFILE
/* Set file access permissions of FILE relative to
the directory FD is open on. */
extern int fchmodat (int __fd, const char *__file, __mode_t __mode,
int __flag)
__THROW __nonnull ((2)) __wur;
#endif /* Use ATFILE. */
/* Set the file creation mask of the current process to MASK,
and return the old creation mask. */
extern __mode_t umask (__mode_t __mask) __THROW;
#ifdef __USE_GNU
/* Get the current `umask' value without changing it.
This function is only available under the GNU Hurd. */
extern __mode_t getumask (void) __THROW;
#endif
/* Create a new directory named PATH, with permission bits MODE. */
extern int mkdir (const char *__path, __mode_t __mode)
__THROW __nonnull ((1));
#ifdef __USE_ATFILE
/* Like mkdir, create a new directory with permission bits MODE. But
interpret relative PATH names relative to the directory associated
with FD. */
extern int mkdirat (int __fd, const char *__path, __mode_t __mode)
__THROW __nonnull ((2));
#endif
/* Create a device file named PATH, with permission and special bits MODE
and device number DEV (which can be constructed from major and minor
device numbers with the `makedev' macro above). */
#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
extern int mknod (const char *__path, __mode_t __mode, __dev_t __dev)
__THROW __nonnull ((1));
# ifdef __USE_ATFILE
/* Like mknod, create a new device file with permission bits MODE and
device number DEV. But interpret relative PATH names relative to
the directory associated with FD. */
extern int mknodat (int __fd, const char *__path, __mode_t __mode,
__dev_t __dev) __THROW __nonnull ((2));
# endif
#endif
/* Create a new FIFO named PATH, with permission bits MODE. */
extern int mkfifo (const char *__path, __mode_t __mode)
__THROW __nonnull ((1));
#ifdef __USE_ATFILE
/* Like mkfifo, create a new FIFO with permission bits MODE. But
interpret relative PATH names relative to the directory associated
with FD. */
extern int mkfifoat (int __fd, const char *__path, __mode_t __mode)
__THROW __nonnull ((2));
#endif
#ifdef __USE_ATFILE
# ifndef __USE_TIME_BITS64
/* Set file access and modification times relative to directory file
descriptor. */
extern int utimensat (int __fd, const char *__path,
const struct timespec __times[2],
int __flags)
__THROW __nonnull ((2));
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (utimensat, (int fd, const char *__path,
const struct timespec __times[2],
int flags),
__utimensat64) __nonnull ((2));
# else
# define utimensat __utimensat64
# endif
# endif
#endif
#ifdef __USE_XOPEN2K8
# ifndef __USE_TIME_BITS64
/* Set file access and modification times of the file associated with FD. */
extern int futimens (int __fd, const struct timespec __times[2]) __THROW;
# else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (futimens, (int fd, const struct timespec __times[2]),
__futimens64);
# else
# define futimens __futimens64
# endif
# endif
#endif
#ifdef __USE_GNU
# include <bits/statx.h>
#endif
__END_DECLS
#endif /* sys/stat.h */
The mode bits 0000070 and 0000007 encode group and others permissions
(see chmod(2)). The defined types, ino_t, off_t, time_t, name various
width integer values; dev_t encodes major and minor device numbers;
their exact definitions are in the include file <sys/types.h> (see
types(5)).
St_atime is the time the file was last read. For reasons of effi‐
ciency, it is not set when a directory is searched, although this would
be more logical. St_mtime is the time the file was last written or
created. It is not set by changes of owner, group, link count, or
mode. St_ctime is set both by writing and and by changing the i-node.
SEE ALSO
ls(1), chmod(2), filsys(5)
DIAGNOSTICS
Zero is returned if a status is available; -1 if the file cannot be
found.
STAT(2)