The ALIAS command lets you change the default PPN (directory) that is used
for file operations on the disk.  ALIAS may be abbreviated to AL.  Some
examples:

    .al abc,def		Sets alias to [ABC,DEF]
    .al abc		Sets alias to [ABC,xxx] where xxx is
			your programmer name
    .al abc,		Sets alias to [ABC,yyy] where yyy is
			your current alias
    .al			Restores alias to your logged-in PPN

Note that the alias command does not check whether you can access files on
the directory or even whether the directory exists; attempts to access
such files will fail when they are tried.  If you need to type a password
to gain access to a directory, use the ACCESS command instead of ALIAS.

If the directory is one of your own, you can avoid having to use ACCESS by
setting the MAS access bit in the directory with the UFD command.  See the
Monitor Command Manual for more information.