NAME
   FreeUnit - deallocate the disk

SYNOPSIS
   FreeUnit( unitNum ), DRResource
              D0         A6

    void FreeUnit(LONG);

FUNCTION
    This routine deallocates one of the units of the disk.  It should
    be called when done with the disk.  Do not call it if you did
    no successfully allocate the disk (there is no protection -- you
    will probably crash the disk system).

INPUTS
    unitNum -- a legal unit number (zero through three)

RESULTS

EXCEPTIONS

SEE ALSO
    FreeUnit

BUGS
    Doesn't check if you own the unit, or even if anyone owns it.