---
name: "mount_msdosfs"
section: "8"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/mount_msdosfs"
---

# mount\_msdosfs(8)

mount an MS-DOS (FAT) file system

## NAME

**mount\_msdosfs** – mount an MS-DOS (FAT) file system

## SYNOPSIS

**mount\_msdosfs** \[**-9ls**\] \[**-D** *DOS\_codepage*\] \[**-g** *gid*\] \[**-L** *locale*\] \[**-M** *mask*\] \[**-m** *mask*\] \[**-o** *options*\] \[**-u** *uid*\] \[**-W** *table*\] *special* *node*

## DESCRIPTION

The **mount\_msdosfs** utility attaches the MS-DOS file system residing on the device *special* to the global file system namespace at the location indicated by *node*. This command is normally executed by [mount(8)](/mount/8.md) 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:

- **-o** *options*

  Use the specified mount *options*, as described in [mount(8)](/mount/8.md). The following MSDOS file system-specific options are available:

  - **longnames**

    Force Windows 95 long filenames to be visible.

  - **shortnames**

    Force only the old MS-DOS 8.3 style filenames to be visible.

  - **nowin95**

    Completely ignore Windows 95 extended file information.

- **-u** *uid*

  Set the owner of the files in the file system to *uid*. The default owner is the owner of the directory on which the file system is being mounted.

- **-g** *gid*

  Set the group of the files in the file system to *gid*. The default group is the group of the directory on which the file system is being mounted.

- **-m** *mask*

  Specify the maximum file permissions for files in the file system. (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)](/chmod/1.md) for more information about octal file modes. Only the nine low-order bits of *mask* are used. The value of *-M* is used if it is supplied and *-m* is omitted. The default *mask* is taken from the directory on which the file system is being mounted.

- **-M** *mask*

  Specify the maximum file permissions for directories in the file system. The value of *-m* is used if it is supplied and *-M* is omitted. See the previous option's description for details.

- **-s**

  Force behaviour to ignore and not generate Win'95 long filenames.

- **-l**

  Force listing and generation of Win'95 long filenames and separate creation/modification/access dates.

  If neither **-s** nor **-l** are given, **-l** is the default.

- **-9**

  Ignore the special Win'95 directory entries even if deleting or renaming a file. This forces **-s**.

- **-L** *locale*

  Specify locale name used for file name conversions for DOS and Win'95 names. By default ISO 8859-1 assumed as local character set.

- **-D** *DOS\_codepage*

  Specify the MS-DOS code page (aka IBM/OEM code page) name used for file name conversions for DOS names.

- **-W** *table*

  This option is preserved for backward compatibility purpose only, and will be removed in the future. Please avoid using this option.

  Specify text file name with conversion table: *iso22dos*, *iso72dos*, *koi2dos*, *koi8u2dos*.

## EXAMPLES

To mount a Russian MS-DOS file system located in */dev/ada1s1*:

```
mount_msdosfs -L ru_RU.KOI8-R -D CP866 /dev/ada1s1 /mnt
```

To mount a Japanese MS-DOS file system located in */dev/ada1s1*:

```
mount_msdosfs -L ja_JP.eucJP -D CP932 /dev/ada1s1 /mnt
```

## SEE ALSO

[mount(2)](/mount/2.md), [unmount(2)](/unmount/2.md), [msdosfs(4)](/msdosfs/4.md), [fstab(5)](/fstab/5.md), [mount(8)](/mount/8.md)

List of Localized MS Operating Systems: *http://www.microsoft.com/globaldev/reference/oslocversion.mspx*.

## HISTORY

The predecessor to **mount\_msdos** utility named **mount\_pcfs** appeared in NetBSD 0.8. It was rewritten in NetBSD 1.0 and first appeared in FreeBSD 2.0. **mount\_msdos** was renamed to the more aptly-named **mount\_msdosfs** in FreeBSD 5.0. The character code conversion routine was added in 2003.

## AUTHORS

Initial implementation as **mount\_pcfs** was written by Paul Popelka ⟨*paulp@uts.amdahl.com*⟩. It was rewritten by Christopher G. Demetriou ⟨*cgd@NetBSD.org*⟩. The character code conversion routine was added by Ryuichiro Imura ⟨*imura@ryu16.org*⟩.

## CAVEATS

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 Win'95.