STAT(S) UNIX System V STAT(S)
Name
stat, fstat - get file status
Syntax
#include <sys/types.h>
#include <sys/stat.h>
int stat (path, buf)
char *path;
struct stat *buf;
int fstat (fildes, buf)
int fildes;
struct stat *buf;
Description
path points to a path name naming a file. Read, write, or
execute permission of the named file is not required, but
all directories listed in the path name leading to the file
must be searchable. The stat system call obtains
information about the named file.
Note that in a Remote File Sharing environment, the
information returned by stat depends upon the user/group
mapping set-up between the local and remote computers (see
idload(ADM)).
fstat obtains information about an open file known by the
file descriptor fildes, obtained from a successful open,
creat, dup, fcntl, or pipe system call.
buf is a pointer to a stat structure into which information
is placed concerning the file.
The contents of the structure pointed to by buf include the
following members:
ushort st_mode; /* File mode [see mknod(S)] */
ino_t st_ino; /* Inode number */
dev_t st_dev; /* ID of device containing */
/* a directory entry for this file */
dev_t st_rdev; /* ID of device */
/* This entry is defined only for */
/* character special or */
/* block special files */
short st_nlink; /* Number of links */
ushort st_uid; /* User ID of the file's owner */
ushort st_gid; /* Group ID of the file's group */
off_t st_size; /* File size in bytes */
time_t st_atime; /* Time of last access */
time_t st_mtime; /* Time of last data modification */
time_t st_ctime; /* Time of last file status change */
/* Times measured in seconds since */
/* 00:00:00 GMT, Jan. 1, 1970 */
st_mode The mode of the file as described in the mknod(S)
system call.
st_ino This field uniquely identifies the file in a given
file system. The pair st_ino and st_dev uniquely
identifies regular files.
st_dev This field uniquely identifies the file system
that contains the file. Its value may be used as
input to the ustat(S) system call to determine
more information about this file system. No other
meaning is associated with this value.
st_rdev This field should be used only by administrative
commands. It is valid only for block special or
character special files and only has meaning on
the system where the file was configured.
st_nlink This field should be used only by administrative
commands.
st_uid The user ID of the file's owner.
st_gid The group ID of the file's group.
st_size For regular files, this is the address of the end
of the file. For pipes or fifos, this is the
count of the data currently in the file. For
block special or character special, this is not
defined.
st_atime Time when file data was last accessed. Changed by
the following system calls: creat(S), mknod(S),
pipe(S), utime(S), and read(S).
st_mtime Time when data was last modified. Changed by the
following system calls: creat(S), mknod(S),
pipe(S), utime(S), and write(S).
st_ctime Time when file status was last changed. Changed
by the following system calls: chmod(S), chown(S),
creat(S), link(S), mknod(S), pipe(S), unlink(S),
utime(S), and write(S).
The stat system call will fail if one or more of the
following is true:
[ENOTDIR] A component of the path prefix is not a
directory.
[ENOENT] The named file does not exist.
[EACCES] Search permission is denied for a component
of the path prefix.
[EFAULT] buf or path points to an invalid address.
[EINTR] A signal was caught during the stat system
call.
[ENOLINK] path points to a remote machine and the link
to that machine is no longer active.
[EMULTIHOP] Components of path require hopping to
multiple remote machines.
Fstat will fail if one or more of the following is true:
[EBADF] fildes is not a valid open file descriptor.
[EFAULT] buf points to an invalid address.
[ENOLINK] fildes points to a remote machine and the
link to that machine is no longer active.
See Also
chmod(S), chown(S), creat(S), link(S), mknod(S), pipe(S),
read(S), time(S), unlink(S), utime(S), write(S)
Diagnostics
Upon successful completion a value of 0 is returned.
Otherwise, a value of -1 is returned, and errno is set to
indicate the error.
Standards Conformance
fstat and stat are conformant with:
AT&T SVID Issue 2, Select Code 307-127;
The X/Open Portability Guide II of January 1987;
IEEE POSIX Std 1003.1-1988 with C Standard Language-
Dependent System Support;
and NIST FIPS 151-1.
(printed 6/20/89)