MOUNT_MSDOS(8)          OpenBSD System Manager's Manual         MOUNT_MSDOS(8)

NAME
     mount_msdos - mount an MS-DOS file system

SYNOPSIS
     mount_msdos [-9lsx] [-g gid] [-m mask] [-o options] [-u uid] special node

DESCRIPTION
     The mount_msdos command attaches the MS-DOS file system residing on the
     device special to the global file system namespace at the location indi-
     cated by node.  This command is invoked by mount(8) when using the syntax

         mount [options] -t msdos special node

     The special device must correspond to a partition registered in the
     disklabel(5).

     This command is normally executed by mount(8) at boot time, but can be
     used by any user to mount an MS-DOS file system on any directory that
     they own (provided, of course, that they have appropriate access to the
     device that contains the file system).

     The options are as follows:

     -9      Ignore the special Windows 95/98 directory entries even if delet-
             ing or renaming a file.  This forces -s.

     -g gid  Set the group of the files in the file system to gid.  The de-
             fault group is the group of the directory on which the file sys-
             tem is being mounted.

     -l      Force listing and generation of Windows 95/98 long filenames and
             separate creation/modification/access dates.

             If neither -s nor -l are given, mount_msdos searches the root di-
             rectory of the file system to be mounted for any existing Windows
             95/98 long filenames.  If no such entries are found, -s is the
             default.  Otherwise -l is assumed.

     -m mask
             Specify the maximum permissions for files and directories in the
             file system.  Only the nine low-order bits of mask are used.

     -o options
             Use the specified mount options, as described in mount(8).

     -s      Force behaviour to ignore and not generate Windows 95/98 long
             filenames.

             If neither -s nor -l are given, mount_msdos searches the root di-
             rectory of the file system to be mounted for any existing Windows
             95/98 long filenames.  If no such entries are found, -s is the
             default.  Otherwise -l is assumed.

     -u uid  Set the owner of the files in the file system to uid.  The de-
             fault owner is the owner of the directory on which the file sys-
             tem is being mounted.

     -x      If a directory is readable, it inherits the x attribute as well.

     File permissions for FAT file systems are imitated, since the file system
     has no real concept of permissions.  The default mask is taken from the
     directory on which the file system is being mounted, except when the -m
     option is used.  FAT does have a ``read only'' mode, in which the
     writable bit is unset.  If such files are found, they are marked non-
     writable; it can be set using chmod -w or unset using chmod +w.

     File modes work the same way for directories.  However if a directory is
     mounted with -x, it will inherit the executable bit if it is readable.
     This can be useful for making files non-executable and directories exe-
     cutable: using -x -m 644 will in most cases give permissions of 755 for
     directories and 644 for files.  See chmod(1) for more information about
     octal file modes.

SEE ALSO
     chmod(1), mount(2), disklabel(5), fstab(5), disklabel(8), mount(8),
     umount(8)

HISTORY
     The mount_msdos utility first appeared in NetBSD 0.9.  Its predecessor,
     the mount_pcfs utility, appeared in NetBSD 0.8, and was abandoned in fa-
     vor of the more aptly named mount_msdos.

CAVEATS
     The maximum file size supported by the MS-DOS file system is one byte
     less than 4GB.  This is a FAT file system limitation, documented by Mi-
     crosoft in Knowledge Base article 314463.

     The MS-DOS file system (even with long filenames) does not support file-
     names with trailing dots or spaces.  Any such characters will be silently
     removed before the directory entry is written.  This too is a FAT file
     system limitation.

     The use of the -9 flag could result in damaged file systems, albeit the
     damage is in part taken care of by procedures similar to the ones used in
     Windows 95/98.

     The default handling for -s and -l will result in empty file systems be-
     ing populated with short filenames only.  To generate long filenames on
     empty DOS file systems use -l.

     Note that Windows 95/98 handles only access dates, but not access times.

OpenBSD 4.5                     August 9, 2009                               2