Using mounted DOS filesystems on a UnixWare system

If you have appropriate privileges (normally root) you can mount a DOS filesystem so that users can access its files directly from the UnixWare system. A general description of mounting filesystems is given in ``About mounting DOS filesystems''.

You can also create a DOS filesystem image on a file using the marry(1M) command, and mount the ``married'' file. See ``Using marry to create filesystem images on files'' for details.

You can use wildcard characters just as you use them with UNIX filesystems.

When accessed from UnixWare, the creation, modification, and access times of DOS files are always identical and use GMT, or Greenwich Mean Time. (UnixWare systems use GMT internally and convert it for you.) This means that files you create in the mounted DOS filesystem will not have consistent times across the operating systems.

Copy programs like tar(1) work as expected.

You can edit DOS files in a mounted DOS filesystem, without first copying them into a UnixWare filesystem. The UnixWare system makes this possible by superimposing certain qualities of UNIX filesystems on the mounted DOS filesystem without changing the actual files. Because UNIX filesystems are highly structured and exist in a multiuser environment, access permissions and file ownership are superimposed on the DOS filesystem when mounted.

As mentioned earlier, DOS does not recognize permissions or ownership. Thus, when a DOS filesystem is mounted on UnixWare, the operating system imposes the following characteristics on it:

• The permissions and ownership of the DOS filesystem are governed by the mount point. For example, if root creates a mount point /X with permissions of 777, all users can read or write the contents of the filesystem. If root creates a mount point with permissions of 700, only root can read or write the contents of the filesystem.

• The ownership of regular files is governed by the mount point. If the mount point is owned by root, all files within the DOS filesystem and any created by other users are all owned by root.

• DOS does not distinguish between users, therefore files can be either readable/writable for everyone, or read-only for everyone. The permissions for regular files are either 0777 for readable/writable files or 0555 for read-only files. When a file is created, the permissions are based on the umask of the creator, but may not be the same as they would be in a normal filesystem. If the umask allows anyone to write to the file, then the permissions are set to 777; if no one can write to the file, the permissions are set to 555. See umask(1) for details.

The major restriction with mounting a DOS floppy or a DOS partition is that DOS applications (for example, your DOS word processing package) cannot be executed under this arrangement.

If you need to use your DOS applications, you (or your system administrator) need to do one of the following:

• Boot the system as a DOS system (a user with appropriate privileges can do this).

• Make the DOS partition the active partition, so that the computer boots DOS by default (a user with appropriate privileges can do this).

• Run Merge from the UNIX partition. (Ask your system administrator if you have this application on your system.)