{Define request block for monitor request to wait for IO completions.

  TYPE
    mmt$rb_wait_io_completion = RECORD
      reqcode: syt$monitor_request_code,
      status: syt$monitor_status,
      pva: ^cell,
    RECEND;

?? PUSH (LISTEXT := ON) ??
*copyc syt$monitor_request_code
*copyc syt$monitor_status
?? POP ??
