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STAT(2)                     BSD System Calls Manual                    STAT(2)

     fstat, fstat64, lstat, lstat64, stat, stat64 -- get file status

     #include <sys/stat.h>

     fstat(int fildes, struct stat *buf);

     fstat64(int fildes, struct stat64 *buf);

     lstat(const char *restrict path, struct stat *restrict buf);

     lstat64(const char *restrict path, struct stat64 *restrict buf);

     stat(const char *restrict path, struct stat *restrict buf);

     stat64(const char *restrict path, struct stat64 *restrict buf);

     The stat() family of functions and their 64 bit variants obtain informa-tion information
     tion about a file. 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.

     Lstat() is like stat() except in the case where the named file is a sym-bolic symbolic
     bolic link, in which case lstat() returns information about the link,
     while stat() returns information about the file the link references.
     Unlike other filesystem 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() obtains the same information about an open file known by the
     file descriptor fildes.

     The buf argument is a pointer to a stat or stat64 structure as defined by
     <sys/stat.h> (both shown below) and into which information is placed con-cerning concerning
     cerning the file.

     struct stat {
         dev_t    st_dev;    /* device inode resides on */
         ino_t    st_ino;    /* inode's number */
         mode_t   st_mode;   /* inode protection mode */
         nlink_t  st_nlink;  /* number or 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 */
         quad_t   st_blocks; /* blocks allocated for file */
         u_long   st_blksize;/* optimal file sys I/O ops blocksize */
         u_long   st_flags;  /* user defined flags for file */
         u_long   st_gen;    /* file generation number */

     struct stat64 {
         dev_t           st_dev;           /* ID of device containing file */
         mode_t          st_mode;          /* Mode of file (see below) */
         nlink_t         st_nlink;         /* Number of hard links */
         ino64_t         st_ino;          /* File serial number */
         uid_t           st_uid;           /* User ID of the file */
         gid_t           st_gid;           /* Group ID of the file */
         dev_t           st_rdev;          /* Device ID */
         struct timespec st_atimespec;     /* time of last access */
         struct timespec st_mtimespec;     /* time of last data modification */
         struct timespec st_ctimespec;     /* time of last status change */
         struct timespec st_birthtimespec; /* time of file creation(birth) */
         off_t           st_size;          /* file size, in bytes */
         blkcnt_t        st_blocks;        /* blocks allocated for file */
         blksize_t       st_blksize;       /* optimal blocksize for I/O */
         uint32_t        st_flags;         /* user defined flags for file */
         uint32_t        st_gen;           /* file generation number */
         int32_t         st_lspare;        /* RESERVED: DO NOT USE! */
         int64_t         st_qspare[2];     /* RESERVED: DO NOT USE! */

     The time-related fields of struct stat and struct stat64 are as follows:

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

     st_mtime         Time when file data 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 modi-fication). modification).
                      fication).  Changed by the chmod(2), chown(2), link(2),
                      mknod(2), rename(2), unlink(2), utimes(2) and write(2)
                      system calls.

     st_birthtime     Time of file creation. Only set once when the file is
                      created. This field is only available in the 64 bit
                      variants. On filesystems where birthtime is not avail-able, available,
                      able, this field holds the ctime instead.

     The size-related fields of the structures 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 chmod(2).

     For a list of the file flags in the st_flags field, see <sys/stat.h> and

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

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

     The fstat() system call will fail if:

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

     [EFAULT]           Sb points to an invalid address.

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

     The lstat() and stat() system calls will fail if:

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

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

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

     [ELOOP]            Too many symbolic links are encountered in translating
                        the pathname.  This is taken to be indicative of a
                        looping symbolic link.

     [ENAMETOOLONG]     A component of a pathname exceeds {NAME_MAX} charac-ters, characters,
                        ters, or an entire path name exceeds {PATH_MAX} char-acters. characters.

     [ENOENT]           The named file does not exist.

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

     The fstat(), lstat(), and stat() system calls will fail if:

     [EOVERFLOW]        The file size in bytes or the number of blocks allo-cated allocated
                        cated to the file or the file serial number cannot be
                        represented correctly in the structure pointed to by

     The file generation number, st_gen, is only available to the super-user.
     The fields in the stat structure currently marked st_spare1, st_spare2,
     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)).

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

     The include file <sys/types.h> is necessary.

     chflags(2), chmod(2), chown(2), utimes(2), compat(5), symlink(7)

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

     The stat() and fstat() function calls are expected to conform to IEEE Std
     1003.1-1988 (``POSIX.1'').

     An lstat() function call appeared in 4.2BSD.  The stat64(), fstat64(),
     and lstat64() system calls first appeared in Mac OS X 10.5 (Leopard).

4th Berkeley Distribution       April 19, 1994       4th Berkeley Distribution