*nix Documentation Project
·  Home
 +   man pages
·  Linux HOWTOs
·  FreeBSD Tips
·  *niX Forums

  man pages->OpenBSD man pages -> fstat (2)              



NAME    [Toc]    [Back]

     stat, lstat, fstat - get file status

SYNOPSIS    [Toc]    [Back]

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

     stat(const char *path, struct stat *sb);

     lstat(const char *path, struct stat *sb);

     fstat(int fd, struct stat *sb);

DESCRIPTION    [Toc]    [Back]

     The stat()  function  obtains  information  about  the  file
pointed to by
     path.   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  lstat() function is identical to stat() except when the
named file is
     a symbolic link, in which case lstat()  returns  information
about the link
     itself, not the file the link references.  Unlike other file
system objects,
 symbolic links do not have an  owner,  group,  access
mode, times,
     etc.  Instead, these attributes are taken from the directory
that contains
 the  link.   The  only  attributes  returned  from  an
lstat() that refer
     to  the  symbolic  link  itself are the file type (S_IFLNK),
size, blocks,
     and link count (always 1).

     The fstat() function obtains the same information  about  an
open file
     known by the file descriptor fd.

     The  sb  argument  is a pointer to a stat() structure as defined by
     <sys/stat.h> (shown below) and  into  which  information  is
placed concerning
 the file.

     struct stat {
         dev_t      st_dev;    /* device inode resides on */
         ino_t      st_ino;    /* inode's number */
         mode_t     st_mode;   /* inode's mode */
         nlink_t     st_nlink;   /*  number  of hard links to the
file */
         uid_t      st_uid;    /* user ID of owner */
         gid_t      st_gid;    /* group ID of owner */
         dev_t      st_rdev;   /* device type, for  special  file
inode */
         struct timespec st_atimespec;  /* time of last access */
         struct timespec st_mtimespec;  /* time of last data modification */
         struct timespec st_ctimespec;  /* time of last file status change */
         off_t      st_size;   /* file size, in bytes */
         int64_t    st_blocks; /* blocks allocated for file */
         u_int32_t  st_blksize;/* optimal file sys I/O ops blocksize */
         u_int32_t  st_flags;  /* user defined flags for file */
         u_int32_t  st_gen;    /* file generation number */

     The time-related fields of struct stat are as follows:

     st_atime     Time when file data was last accessed.  Changed
by the
                  mknod(2), utimes(2), and read(2) system  calls.

     st_mtime     Time when file data was last modified.  Changed
by the
                  mknod(2), utimes(2), and write(2) system calls.

     st_ctime      Time  when file status was last changed (inode
data modification).
   Changed  by  the  chmod(2),  chown(2),
                  mknod(2),  rename(2), unlink(2), utimes(2), and
write(2) system

     The size-related fields of the struct stat are as follows:

     st_blksize     The optimal I/O block size for the file.

     st_blocks      The actual number of blocks allocated for the
file in
                    512-byte  units.  As short symbolic links are
stored in the
                    inode, this number may be zero.

     The status information word st_mode has the following bits:

     #define S_IFMT   0170000  /* type of file */
     #define S_IFIFO  0010000  /* named pipe (fifo) */
     #define S_IFCHR  0020000  /* character special */
     #define S_IFDIR  0040000  /* directory */
     #define S_IFBLK  0060000  /* block special */
     #define S_IFREG  0100000  /* regular */
     #define S_IFLNK  0120000  /* symbolic link */
     #define S_IFSOCK 0140000  /* socket */
     #define S_IFWHT  0160000  /* whiteout */
     #define S_ISUID  0004000  /* set-user-ID on execution */
     #define S_ISGID  0002000  /* set-group-ID on execution */
     #define S_ISVTX  0001000  /* save swapped  text  even  after
use */
     #define S_IRUSR  0000400  /* read permission, owner */
     #define S_IWUSR  0000200  /* write permission, owner */
     #define S_IXUSR  0000100  /* execute/search permission, owner */

     For a list of access modes, see <sys/stat.h>, access(2), and

RETURN VALUES    [Toc]    [Back]

     Upon successful completion a value of 0 is returned.  Otherwise, a value
     of -1 is returned and errno is set to indicate the error.

ERRORS    [Toc]    [Back]

     stat() and lstat() will fail if:

     [ENOTDIR]     A component of the path prefix is not a directory.

                   A  component  of  a pathname exceeded NAME_MAX
characters, or
                   an entire path name exceeded PATH_MAX  characters.

     [ENOENT]      The named file does not exist.

     [EACCES]      Search permission is denied for a component of
the path

     [ELOOP]       Too many symbolic links  were  encountered  in
translating the

     [EFAULT]      sb or name points to an invalid address.

     [EIO]          An  I/O  error occurred while reading from or
writing to the
                   file system.

     fstat() will fail if:

     [EBADF]       fd is not a valid open file descriptor.

     [EFAULT]      sb points to an invalid address.

     [EIO]         An I/O error occurred while  reading  from  or
writing to the
                   file system.

SEE ALSO    [Toc]    [Back]

     chmod(2), chown(2), utimes(2), symlink(7)

STANDARDS    [Toc]    [Back]

     Previous versions of the system used different types for the
     st_uid, st_gid, st_rdev, st_size, st_blksize, and  st_blocks

     The  stat()  and fstat() function calls are expected to conform to IEEE Std
     1003.1-1988 (``POSIX'').

HISTORY    [Toc]    [Back]

     A stat() function appeared  in  Version  2  AT&T  UNIX.   An
lstat() function
     call appeared in 4.2BSD.

CAVEATS    [Toc]    [Back]

     The file generation number, st_gen, is only available to the

     The fields in the stat structure currently marked st_spare1,
     and  st_spare3  are  present  in  preparation for inode time
stamps expanding
     to 64 bits.  This, however, can break certain programs  that
depend on the
     time stamps being contiguous (in calls to utimes(2)).

BUGS    [Toc]    [Back]

     Applying  fstat() to a socket (and thus to a pipe) returns a
     buffer, except for the blocksize field, and a unique  device
and inode

OpenBSD      3.6                          April      19,     1994
[ Back ]
 Similar pages
Name OS Title
kldstat FreeBSD get status of kld file
pxfstat IRIX Retrieves the file status
stat FreeBSD display file status
readlink FreeBSD display file status
check IRIX check RCS status of a file
pthread_exc_get_status_np Tru64 (Macro) Obtains a systemdefined error status from a DECthreads status exception object
VFS_STATFS FreeBSD return file system status
stl_sts Tru64 setld subset status file
fsclean_hfs HP-UX determine the shutdown status of HFS file systems
sm Tru64 Status monitor directories and file structures
Copyright © 2004-2005 DeniX Solutions SRL
newsletter delivery service