NAME

     stat, lstat, fstat - get file status


SYNOPSIS

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

     int stat(const char *path, struct stat *buf)
     int lstat(const char *path, struct stat *buf)         (Minix-vmd)
     int fstat(int fd, struct stat *buf)


DESCRIPTION

     Stat obtains information about the file 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 reachable.

     Lstat is like stat except in the case where the  named  file
     is  a symbolic link, in which case lstat returns information
     about the link, while stat  returns  information  about  the
     file  the  link references.  (Minix-vmd) (Under minix, lstat
     behaves like stat.)

     Fstat obtains the same information about an open file refer-
     enced  by the argument descriptor, such as would be obtained
     by an open call.  Pipe descriptors  look  like  named  pipes
     with  a  link  count of zero.  The st_size field of pipes or
     named pipes shows the amount of bytes currently buffered  in
     the pipe.

     Buf is a pointer to a stat structure into which  information
     is  placed  concerning the file.  The contents of the struc-
     ture pointed to by buf is as follows:

     struct stat {
         dev_t   st_dev;   /* device inode resides on */
         ino_t   st_ino;   /* this inode's number */
         mode_t  st_mode;  /* file mode, protection bits, etc. */
         nlink_t st_nlink; /* number or hard links to the file */
         uid_t   st_uid;   /* user-id of the file's owner */
         gid_t   st_gid;   /* group-id of the file's owner */
         dev_t   st_rdev;  /* the device type, for inode that is device */
         off_t   st_size;  /* total size of file */
         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 */
     };

     st_atime    Time when file data was last read  or  modified.
                 Changed   by   the   following   system   calls:
                 mknod(2), utime(2), read(2), and write(2).   For
                 reasons  of efficiency, st_atime is not set when
                 a directory is searched, although this would  be
                 more logical.

     st_mtime    Time when data was last modified.  It is not set
                 by changes of owner, group, link count, or mode.
                 Changed   by   the   following   system   calls:
                 mknod(2), utime(2), write(2).

     st_ctime    Time when file status was last changed.   It  is
                 set  both  both  by  writing and changing the i-
                 node.  Changed by the  following  system  calls:
                 chmod(2) chown(2), link(2), mknod(2), rename(2),
                 unlink(2), utime(2), write(2).

     The file type information in st_mode has bits:

          #define S_IFMT  0170000  /* type of file */
          #define    S_IFIFO       0010000/* named pipe */
          #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 (Minix-vmd) */

     The mode bits 0007777 encode set-uid/gid bits and permission
     bits (see chmod(2)).


RETURN VALUE

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


ERRORS

     Stat and lstat will fail if one or more of the following are
     true:

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

     [ENAMETOOLONG] The path name exceeds PATH_MAX characters.

     [ENOENT]       The named file does not exist.

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

     [ELOOP]        Too many symbolic links were  encountered  in
                    translating the pathname.  (Minix-vmd)

     [EFAULT]       Buf 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 one or both of the following are true:

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

     [EFAULT]       Buf points to an invalid address.

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


SEE ALSO

     chmod(2), chown(2), utime(2).