--background-- 
     CallErrHook() 
     CMD_FLUSH 
     CMD_INVALID 
     CMD_RESET 
     CMD_START 
     CMD_STOP 
     CMD_WRITE 
     PBothReady() 
     PRD_DUMPRPORT 
     PRD_DUMPRPORTTAGS 
     PRD_EDITPREFS 
     PRD_PRTCOMMAND 
     PRD_QUERY 
     PRD_RAWWRITE 
     PRD_READPREFS 
     PRD_SETERRHOOK 
     PRD_WRITEPREFS 
     PQuery() 
     PRead() 
     PWrite()