mount -- Command

Mount a file system
/etc/mount [ device directory [ -ru ] ]

The  command mount  mounts a  file  system from  device onto  directory. In
effect,  it  grafts  the root  directory  of  file  system  on device  onto
directory.


If you  invoke mount without  any arguments, it  displays information about
the file systems that are now mounted.

If you use  option -r, mount mounts the specified  file system in read-only
mode.  This is useful if you wish to read a file system without changing it
in any such  way, such as when you are  backing it up.  Note, however, that
when a file  system is mounted in read-only mode,  COHERENT does not update
file-system information, such the time a file was last accessed.

The  option -u  tells mount  to write  an entry  into the  mount-table file
/etc/mtab without  actually mounting the  file system.  When  this is done,
COHERENT will  hereafter mount the  file system automatically  whenever you
boot COHERENT.

Please note that unlike every  other COHERENT or UNIX command ever devised,
mount requires that its options  follow the file names, rather than precede
them.  The  COHERENT version of  mount follows this convention  in order to
conform to this established UNIX practice.

To  un-mount a  file system,  use the  command umount. (NB,  this is  not a
typographical error -- this command's name contains only one `n'.)

The   script   /bin/mount  calls   /etc/mount,   and  provides   convenient
abbreviations for commonly used devices.  For example,

    mount f0

executes the command:

    /etc/mount /dev/fha0 /f0

You should  edit this script  to reflect the  devices that you  use on your
system.

Files

/etc/mtab -- Mount table
/etc/mnttab -- Mount table
/bin/mount -- Shell script that calls /etc/mount

See Also

commands,
fsck,
mkfs,
mknod,
umount

Diagnostics

Errors can  occur if device  or directory does  not exist or if  you do not
have permission to access device.

The message

    /etc/mtab older than /etc/boottime

indicates  that /etc/mtab  has  probably been  invalidated  by booting  the
system.

Attempting to  mount a block-special file that does  not contain a COHERENT
file system (e.g., a tape device) can have disastrous consequences.  Caveat
utilitor! To build a file system on a block-special device, use the command
/etc/mkfs. For details, see its entry in the Lexicon.

© 2012 by Stephen A. Ness