MOUNT_MSDOS(8) BSD System Manager's Manual MOUNT_MSDOS(8)
mount_msdos - mount an MS-DOS filesystem
mount_msdos [-o options] [-u uid] [-g gid] [-m mask] [-s] [-l] [-9] [-G]
[-x] special node
The mount_msdos command attaches the MS-DOS filesystem residing on the
device special to the global filesystem 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 filesystem on any directory that they
own (provided, of course, that they have appropriate access to the device
that contains the filesystem).
The options are as follows:
-o options
Use the specified mount options, as described in mount(8).
-u uid Set the owner of the files in the filesystem to uid. The default
owner is the owner of the directory on which the filesystem is
being mounted.
-g gid Set the group of the files in the filesystem to gid. The default
group is the group of the directory on which the filesystem is
being mounted.
-m mask
Specify the maximum file permissions for files in the filesystem.
(For example, a mask of 755 specifies that, by default, the owner
should have read, write, and execute permissions for files, but
others should only have read and execute permissions. See
chmod(1) for more information about octal file modes.) Only the
nine low-order bits of mask are used. The default mask is taken
from the directory on which the filesystem is being mounted.
-s Force behaviour to ignore and not generate Windows 95/98 long
filenames.
-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
directory of the filesystem to be mounted for any existing Win-
dows 95/98 long filenames. If no such entries are found, -s is
the default. Otherwise -l is assumed.
-9 Ignore the special Windows 95/98 directory entries even if delet-
ing or renaming a file. This forces -s.
-G This option causes the filesystem to be interpreted as an Atari-
Gemdos filesystem. The differences to the MS-DOS filesystem are
minimal and limited to the boot block. This option enforces -9.
-x If a directory is readable, it inherits the x attribute as well.
mount(2), disklabel(5), fstab(5), disklabel(8), mount(8), umount(8)
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
favor of the more aptly named mount_msdos.
The maximum file size supported by the MS-DOS filesystem is one byte less
than 4GB. This is a FAT filesystem limitation, documented by Microsoft in
Knowledge Base article 314463.
The MS-DOS filesystem (even with long filenames) does not support
filenames with trailing dots or spaces. Any such characters will be
silently removed before the directory entry is written. This too is a FAT
filesystem limitation.
The use of the -9 flag could result in damaged filesystems, 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 filesystems being
populated with short filenames only. To generate long filenames on empty
DOS filesystems use -l.
Note that Windows 95/98 handles only access dates, but not access times.
Due to the German patent 69429378 (EP0618540), long file names are
currently not supported at all. Partial support by means of a code
rewrite is, however, planned.
MirBSD #10-current August 7, 2017 1