MPPClose
MPPClose Remove .MPP driver
#include <AppleTalk.h> AppleTalk Manager
returns Error Code; 0=no error
MPPClose removes the .MPP driver and any data structures associated with
it from memory.
Returns: an OSErr; an integer Error Code. It will be one of:
noErr (0) No error
portInUse (-97) Port B is already in use
portNotCf (-98) Port B not configured for AppleTalk

Notes: If the .ATP driver or NBP code were also installed, they're removed as
well. MPPClose also returns the use of port B to the Serial Driver.
Warning: Since other co-resident programs may be using AppleTalk, it's
strongly recommended that you never use this call. MPPClose will
completely disable AppleTalk; the only way to restore AppleTalk is to call
MPPOpen again.