If, for some twisted and bizarre reason, you would have need to access files from MS-DOS, it's quite easily done under Linux.
The usual way to access MS-DOS files is to mount an MS-DOS partition or floppy under Linux, allowing you to access the files directly through the filesystem. For example, if you have an MS-DOS floppy in /dev/fd0, the command
# mount -t msdos /dev/fd0 /mnt
will mount it under /mnt. See Section 4.6.2 for more information on mounting floppies.
You can also mount an MS-DOS partition of your hard drive for access under Linux. If you have an MS-DOS partition on /dev/hda1, the command
# mount -t msdos /dev/hda1 /mnt
will mount it. Be sure to umount the partition when you're done using it. You can have your MS-DOS partitions automatically mounted at boot time if you include entries for them in /etc/fstab; see Section 4.8 for details. For example, the following line in /etc/fstab will mount an MS-DOS partition on /dev/hda1 on the directory /dos.
/dev/hda1 /dos msdos defaults
The Mtools software may also be used to access MS-DOS files. For example, the commands mcd, mdir, and mcopy all behave as their MS-DOS counterparts. If you installed Mtools, there should be man pages available for these commands.
Accessing MS-DOS files is one thing; running MS-DOS programs from Linux is another. There is an MS-DOS Emulator under development for Linux; it is widely available, and even distributed with SLS. It can be retrieved from a number of locations, including the various Linux FTP sites (see Appendix C for details). The MS-DOS Emulator is reportedly powerful enough to run a number of applications, including Wordperfect, from Linux. However, Linux and MS-DOS are vastly different operating systems. The power of any MS-DOS emulator under UNIX is somewhat limited.
In addition, work is underway on a Microsoft Windows emulator to run under X Windows. Watch the newsgroups and FTP sites for more information.