Provided by: manpages-dev_2.17-1_all bug


       statfs, fstatfs - get file system statistics


       #include <sys/vfs.h>    /* or <sys/statfs.h> */

       int statfs(const char *path, struct statfs *buf);
       int fstatfs(int fd, struct statfs *buf);


       The  function statfs() returns information about a mounted file system.
       path is the path name of any file within the mounted  filesystem.   buf
       is a pointer to a statfs structure defined approximately as follows:

              struct statfs {
                 long    f_type;     /* type of filesystem (see below) */
                 long    f_bsize;    /* optimal transfer block size */
                 long    f_blocks;   /* total data blocks in file system */
                 long    f_bfree;    /* free blocks in fs */
                 long    f_bavail;   /* free blocks avail to non-superuser */
                 long    f_files;    /* total file nodes in file system */
                 long    f_ffree;    /* free file nodes in fs */
                 fsid_t  f_fsid;     /* file system id */
                 long    f_namelen;  /* maximum length of filenames */

              File system types:

                 ADFS_SUPER_MAGIC      0xadf5
                 AFFS_SUPER_MAGIC      0xADFF
                 BEFS_SUPER_MAGIC      0x42465331
                 BFS_MAGIC             0x1BADFACE
                 CIFS_MAGIC_NUMBER     0xFF534D42
                 CODA_SUPER_MAGIC      0x73757245
                 COH_SUPER_MAGIC       0x012FF7B7
                 CRAMFS_MAGIC          0x28cd3d45
                 DEVFS_SUPER_MAGIC     0x1373
                 EFS_SUPER_MAGIC       0x00414A53
                 EXT_SUPER_MAGIC       0x137D
                 EXT2_OLD_SUPER_MAGIC  0xEF51
                 EXT2_SUPER_MAGIC      0xEF53
                 EXT3_SUPER_MAGIC      0xEF53
                 HFS_SUPER_MAGIC       0x4244
                 HPFS_SUPER_MAGIC      0xF995E849
                 HUGETLBFS_MAGIC       0x958458f6
                 ISOFS_SUPER_MAGIC     0x9660
                 JFFS2_SUPER_MAGIC     0x72b6
                 JFS_SUPER_MAGIC       0x3153464a
                 MINIX_SUPER_MAGIC     0x137F /* orig. minix */
                 MINIX_SUPER_MAGIC2    0x138F /* 30 char minix */
                 MINIX2_SUPER_MAGIC    0x2468 /* minix V2 */
                 MINIX2_SUPER_MAGIC2   0x2478 /* minix V2, 30 char names */
                 MSDOS_SUPER_MAGIC     0x4d44
                 NCP_SUPER_MAGIC       0x564c
                 NFS_SUPER_MAGIC       0x6969
                 NTFS_SB_MAGIC         0x5346544e
                 OPENPROM_SUPER_MAGIC  0x9fa1
                 PROC_SUPER_MAGIC      0x9fa0
                 QNX4_SUPER_MAGIC      0x002f
                 REISERFS_SUPER_MAGIC  0x52654973
                 ROMFS_MAGIC           0x7275
                 SMB_SUPER_MAGIC       0x517B
                 SYSV2_SUPER_MAGIC     0x012FF7B6
                 SYSV4_SUPER_MAGIC     0x012FF7B5
                 TMPFS_MAGIC           0x01021994
                 UDF_SUPER_MAGIC       0x15013346
                 UFS_MAGIC             0x00011954
                 USBDEVICE_SUPER_MAGIC 0x9fa2
                 VXFS_SUPER_MAGIC      0xa501FCF5
                 XENIX_SUPER_MAGIC     0x012FF7B4
                 XFS_SUPER_MAGIC       0x58465342
                 _XIAFS_SUPER_MAGIC    0x012FD16D

       Nobody knows what f_fsid is supposed to contain (but see below).

       Fields  that  are  undefined for a particular file system are set to 0.
       fstatfs() returns the same information about an open file referenced by
       descriptor fd.


       On  success,  zero is returned.  On error, -1 is returned, and errno is
       set appropriately.


       EACCES (statfs()) Search permission is denied for a  component  of  the
              path prefix of path.  (See also path_resolution(2).)

       EBADF  (fstatfs()) fd is not a valid open file descriptor.

       EFAULT buf or path points to an invalid address.

       EINTR  This call was interrupted by a signal.

       EIO    An I/O error occurred while reading from the file system.

       ELOOP  (statfs())   Too   many   symbolic  links  were  encountered  in
              translating path.

              (statfs()) path is too long.

       ENOENT (statfs()) The file referred to by path does not exist.

       ENOMEM Insufficient kernel memory was available.

       ENOSYS The file system does not support this call.

              (statfs()) A component of the path  prefix  of  path  is  not  a

              Some  values  were  too  large to be represented in the returned


       The Linux statfs() was inspired by the 4.4BSD one (but they do not  use
       the same structure).

NOTES ON f_fsid

       Solaris,  Irix  and  POSIX have a system call statvfs(2) that returns a
       struct statvfs (defined in <sys/statvfs.h>) containing an unsigned long
       f_fsid.   Linux,  SunOS,  HPUX, 4.4BSD have a system call statfs() that
       returns a struct statfs (defined in <sys/vfs.h>)  containing  a  fsid_t
       f_fsid,  where  fsid_t  is defined as struct { int val[2]; }.  The same
       holds for FreeBSD, except that it uses the include file  <sys/mount.h>.

       The  general  idea  is that f_fsid contains some random stuff such that
       the pair (f_fsid,ino) uniquely determines a file.   Some  OSes  use  (a
       variation on) the device number, or the device number combined with the
       filesystem type.  Several OSes restrict giving out the f_fsid field  to
       the  superuser only (and zero it for nonprivileged users), because this
       field is used in the filehandle of the  filesystem  when  NFS-exported,
       and giving it out is a security concern.

       Under some OSes the fsid can be used as second parameter to the sysfs()
       system call.


       The kernel  has  system  calls  statfs(),  fstatfs(),  statfs64(),  and
       fstatfs64() to support this library call.

       Some   systems   only   have   <sys/vfs.h>,  other  systems  also  have
       <sys/statfs.h>, where the former  includes  the  latter.  So  it  seems
       including the former is the best choice.

       LSB  has  deprecated the library calls statfs() and fstatfs() and tells
       us to use statvfs() and statvfs() instead.


       path_resolution(2), stat(2), statvfs(2)