fstab

NAME

       fstab - static information about the filesystems

SYNOPSIS

       #include <fstab.h>

DESCRIPTION

       The  file fstab contains descriptive information about the
       various file systems.  fstab is only read by programs, and
       not written; it is the duty of the system administrator to
       properly create and maintain this file.   Each  filesystem
       is  described  on a separate line; fields on each line are
       separated by tabs or spaces.   The  order  of  records  in
       fstab   is   important   because  fsck(8),  mount(8),  and
       umount(8) sequentially iterate through fstab  doing  their
       thing.

       The  first  field,  (fs_spec), describes the block special
       device or remote filesystem to be mounted.

       The second field, (fs_file), describes the mount point for
       the filesystem.  For swap partitions, this field should be
       specified as ``none''.

       The third field, (fs_vfstype), describes the type  of  the
       filesystem.   The system currently supports three types of
       filesystems:

       minix  a local filesystem, supporting filenames of  length
              14 or 30 characters.

       ext    a local filesystem with longer filenames and larger
              inodes.  This filesystem has been replaced  by  the
              ext2 file system, and should no longer be used.

       ext2   a  local  filesystem  with longer filenames, larger
              inodes, and lots of other features.

       xiafs  a local filesystem with  longer  filenames,  larger
              inodes, and lots of other features.

       msdos  a local filesystem for MS-DOS partitions.

       hpfs   a local filesystem for HPFS partitions.

       iso9660
              a local filesystem used for CD-ROM drives.

       nfs    a  filesystem  for  mounting partitions from remote
              systems.

       swap   a disk partition to be used for swapping.

       If vfs_fstype is specified  as  ``ignore''  the  entry  is
       ignored.  This is useful to show disk partitions which are
       currently unused.

       The fourth field, (fs_mntops), describes the mount options
       associated with the filesystem.

       It  is formatted as a comma separated list of options.  It
       contains at least the type of mount  plus  any  additional
       options  appropriate to the filesystem type.  For documen-
       tation on the available options for non-nfs file  systems,
       see  mount(8).   For  documentation  on  all  nfs-specific
       options have a look at nfs(5).

       The fifth field, (fs_freq), is used for these  filesystems
       by the dump(8) command to determine which filesystems need
       to be dumped.  If the fifth field is not present, a  value
       of zero is returned and dump will assume that the filesys-
       tem does not need to be dumped.

       The sixth field, (fs_passno), is used by the fsck(8)  pro-
       gram to determine the order in which filesystem checks are
       done at reboot time.  The root filesystem should be speci-
       fied  with  a fs_passno of 1, and other filesystems should
       have a fs_passno of 2.  Filesystems within a drive will be
       checked  sequentially, but filesystems on different drives
       will be checked at the same time  to  utilize  parallelism
       available in the hardware.  If the sixth field is not pre-
       sent or zero, a value of zero is returned  and  fsck  will
       assume that the filesystem does not need to be checked.

       The  proper  way  to read records from fstab is to use the
       routines getmntent(3).

FILES

       /etc/fstab The file fstab resides in /etc.

BUGS

       The documentation in mount(8) is often more up-to-date.

SEE ALSO

       getmntent(3), mount(8), swapon(8), nfs(5)

HISTORY

       The fstab file format appeared in 4.0BSD.