Creates a user-mode logical name in the specified table.
If you specify a user-mode logical name in the process logical
name table, that logical name is used for the execution of
a single image only; user-mode entries are deleted from the
logical name table when any image executing in the process
exits; that is, after any DCL command that executes an image or
user program completes execution. Also, user-mode logical names
are automatically deleted when invoking and exiting a command
procedure.