STAT(2)STAT(2)NAME
stat, fstat - get file status
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
stat(name, buf)
char *name;
struct stat *buf;
fstat(fildes, buf)
struct stat *buf;
DESCRIPTION
Stat obtains detailed information about a named file. Fstat obtains
the same information about an open file known by the file descriptor
from a successful open, creat, dup or pipe(2) call.
Name points to a null-terminated string naming a file; buf is the
address 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 as defined in <stat.h> is
given below. St_mode is encoded according to the `#define' statements.
/* Copyright (C) 1991, 1992, 1995-2004, 2005, 2006, 2007, 2009, 2010
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
/*
* 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. */
#if defined __USE_XOPEN || defined __USE_XOPEN2K || defined __USE_MISC || defined __USE_ATFILE
# if defined __USE_XOPEN || defined __USE_XOPEN2K
# define __need_time_t
# endif
# if defined __USE_MISC || defined __USE_ATFILE
# define __need_timespec
# endif
# include <time.h> /* For time_t resp. timespec. */
#endif
#if defined __USE_XOPEN || defined __USE_XOPEN2K
/* The Single Unix specification says that some more types are
available here. */
# 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_BSD || 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_BSD || defined __USE_MISC || defined __USE_UNIX98) && 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_BSD && !defined __S_IFLNK
# define S_ISLNK(mode) 0
#endif
#if (defined __USE_BSD || defined __USE_UNIX98 || 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_BSD || 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)
#if defined __USE_MISC && defined __USE_BSD
# 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_BSD
/* 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 __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
#ifdef __USE_LARGEFILE64
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));
#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 __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
# ifdef __USE_LARGEFILE64
extern int fstatat64 (int __fd, __const char *__restrict __file,
struct stat64 *__restrict __buf, int __flag)
__THROW __nonnull ((2, 3));
# endif
#endif
#if defined __USE_BSD || 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 __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
# ifdef __USE_LARGEFILE64
extern int lstat64 (__const char *__restrict __file,
struct stat64 *__restrict __buf)
__THROW __nonnull ((1, 2));
# 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_BSD
/* 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_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
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_BSD || 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
/* 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));
#endif
#ifdef __USE_XOPEN2K8
/* Set file access and modification times of the file associated with FD. */
extern int futimens (int __fd, __const struct timespec __times[2]) __THROW;
#endif
/* To allow the `struct stat' structure and the file type `mode_t'
bits to vary without changing shared library major version number,
the `stat' family of functions and `mknod' are in fact inline
wrappers around calls to `xstat', `fxstat', `lxstat', and `xmknod',
which all take a leading version-number argument designating the
data structure and bits used. <bits/stat.h> defines _STAT_VER with
the version number corresponding to `struct stat' as defined in
that file; and _MKNOD_VER with the version number corresponding to
the S_IF* macros defined therein. It is arranged that when not
inlined these function are always statically linked; that way a
dynamically-linked executable always encodes the version number
corresponding to the data structures it uses, so the `x' functions
in the shared library can adapt without needing to recompile all
callers. */
#ifndef _STAT_VER
# define _STAT_VER 0
#endif
#ifndef _MKNOD_VER
# define _MKNOD_VER 0
#endif
/* Wrappers for stat and mknod system calls. */
#ifndef __USE_FILE_OFFSET64
extern int __fxstat (int __ver, int __fildes, struct stat *__stat_buf)
__THROW __nonnull ((3));
extern int __xstat (int __ver, __const char *__filename,
struct stat *__stat_buf) __THROW __nonnull ((2, 3));
extern int __lxstat (int __ver, __const char *__filename,
struct stat *__stat_buf) __THROW __nonnull ((2, 3));
extern int __fxstatat (int __ver, int __fildes, __const char *__filename,
struct stat *__stat_buf, int __flag)
__THROW __nonnull ((3, 4));
#else
# ifdef __REDIRECT_NTH
extern int __REDIRECT_NTH (__fxstat, (int __ver, int __fildes,
struct stat *__stat_buf), __fxstat64)
__nonnull ((3));
extern int __REDIRECT_NTH (__xstat, (int __ver, __const char *__filename,
struct stat *__stat_buf), __xstat64)
__nonnull ((2, 3));
extern int __REDIRECT_NTH (__lxstat, (int __ver, __const char *__filename,
struct stat *__stat_buf), __lxstat64)
__nonnull ((2, 3));
extern int __REDIRECT_NTH (__fxstatat, (int __ver, int __fildes,
__const char *__filename,
struct stat *__stat_buf, int __flag),
__fxstatat64) __nonnull ((3, 4));
# else
# define __fxstat __fxstat64
# define __xstat __xstat64
# define __lxstat __lxstat64
# endif
#endif
#ifdef __USE_LARGEFILE64
extern int __fxstat64 (int __ver, int __fildes, struct stat64 *__stat_buf)
__THROW __nonnull ((3));
extern int __xstat64 (int __ver, __const char *__filename,
struct stat64 *__stat_buf) __THROW __nonnull ((2, 3));
extern int __lxstat64 (int __ver, __const char *__filename,
struct stat64 *__stat_buf) __THROW __nonnull ((2, 3));
extern int __fxstatat64 (int __ver, int __fildes, __const char *__filename,
struct stat64 *__stat_buf, int __flag)
__THROW __nonnull ((3, 4));
#endif
extern int __xmknod (int __ver, __const char *__path, __mode_t __mode,
__dev_t *__dev) __THROW __nonnull ((2, 4));
extern int __xmknodat (int __ver, int __fd, __const char *__path,
__mode_t __mode, __dev_t *__dev)
__THROW __nonnull ((3, 5));
#if defined __GNUC__ && __GNUC__ >= 2 && defined __USE_EXTERN_INLINES
/* Inlined versions of the real stat and mknod functions. */
__extern_inline int
__NTH (stat (__const char *__path, struct stat *__statbuf))
{
return __xstat (_STAT_VER, __path, __statbuf);
}
# if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
__extern_inline int
__NTH (lstat (__const char *__path, struct stat *__statbuf))
{
return __lxstat (_STAT_VER, __path, __statbuf);
}
# endif
__extern_inline int
__NTH (fstat (int __fd, struct stat *__statbuf))
{
return __fxstat (_STAT_VER, __fd, __statbuf);
}
# ifdef __USE_ATFILE
__extern_inline int
__NTH (fstatat (int __fd, __const char *__filename, struct stat *__statbuf,
int __flag))
{
return __fxstatat (_STAT_VER, __fd, __filename, __statbuf, __flag);
}
# endif
# if defined __USE_MISC || defined __USE_BSD
__extern_inline int
__NTH (mknod (__const char *__path, __mode_t __mode, __dev_t __dev))
{
return __xmknod (_MKNOD_VER, __path, __mode, &__dev);
}
# endif
# ifdef __USE_ATFILE
__extern_inline int
__NTH (mknodat (int __fd, __const char *__path, __mode_t __mode,
__dev_t __dev))
{
return __xmknodat (_MKNOD_VER, __fd, __path, __mode, &__dev);
}
# endif
# if defined __USE_LARGEFILE64 && (! defined __USE_FILE_OFFSET64 || (defined __REDIRECT_NTH && defined __OPTIMIZE__))
__extern_inline int
__NTH (stat64 (__const char *__path, struct stat64 *__statbuf))
{
return __xstat64 (_STAT_VER, __path, __statbuf);
}
# if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
__extern_inline int
__NTH (lstat64 (__const char *__path, struct stat64 *__statbuf))
{
return __lxstat64 (_STAT_VER, __path, __statbuf);
}
# endif
__extern_inline int
__NTH (fstat64 (int __fd, struct stat64 *__statbuf))
{
return __fxstat64 (_STAT_VER, __fd, __statbuf);
}
# ifdef __USE_ATFILE
__extern_inline int
__NTH (fstatat64 (int __fd, __const char *__filename, struct stat64 *__statbuf,
int __flag))
{
return __fxstatat64 (_STAT_VER, __fd, __filename, __statbuf, __flag);
}
# endif
# endif
#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).
When fildes is associated with a pipe, fstat reports an ordinary file
with restricted permissions. The size is the number of bytes queued in
the pipe.
st_atime is the file was last read. For reasons of efficiency, it is
not set when a directory is searched, although this would be more logi‐
cal. 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 both by writing and changing the i-node.
SEE ALSOls(1), filsys(5)DIAGNOSTICS
Zero is returned if a status is available; -1 if the file cannot be
found.
ASSEMBLER
(stat = 18.)
sys stat; name; buf
(fstat = 28.)
(file descriptor in r0)
sys fstat; buf
STAT(2)
