.MACRO  CALL_WRTMAILBOX SAVE_R1

	.GLOBAL	EXE_STD$WRTMAILBOX

        $PUSH64_R1 SAVE_R1
        PUSHL   R4
        PUSHL   R3
        PUSHL   R5
        CALLS   #3,G^EXE_STD$WRTMAILBOX

        $POP64_R1 SAVE_R1

        .ENDM   CALL_WRTMAILBOX