MQXWAIT - Wait in exit

The MQXWAIT call waits for an event to occur. It can be used only from a channel exit on z/OS®.

The use of MQXWAIT helps to avoid performance problems that might otherwise occur if a channel exit does something that causes a wait. The event MQXWAIT is waiting on is signaled by an MVS ECB (event control block). The ECB is described in the MQXWD control block description.

For more information about the use of MQXWAIT and writing channel-exit programs, see Writing channel exit programs on z/OS


Syntax

    MQXWAIT (Hconn, WaitDesc, CompCode, Reason)


Parameters

The MQXWAIT call has the following parameters.

    Hconn (MQHCONN) - input

    Connection handle.

    This handle represents the connection to the queue manager. The value of Hconn was returned by a previous MQCONN call issued in the same or earlier invocation of the exit.

    WaitDesc (MQXWD) - input/output

    Wait descriptor.

    This parameter describes the event to wait for. See MQXWD - Exit wait descriptor for details of the fields in this structure.

    CompCode (MQLONG) - output

    Completion code.

    It is one of the following codes:

      MQCC_OK
      Successful completion.

      MQCC_FAILED
      Call failed.

    Reason (MQLONG) - output

    Reason code qualifying CompCode.

    If CompCode is MQCC_OK:

      MQRC_NONE
      (0, X'000') No reason to report.

      MQRC_ADAPTER_NOT_AVAILABLE
      (2204, X'89C') Adapter not available.

      MQRC_OPTIONS_ERROR
      (2046, X'7FE') Options not valid or not consistent.

      MQRC_XWAIT_CANCELED
      (2107, X'83B') MQXWAIT call canceled.

      MQRC_XWAIT_ERROR
      (2108, X'83C') Invocation of MQXWAIT call not valid.


C invocation

MQXWAIT (Hconn, &WaitDesc, &CompCode, &Reason);
Declare the parameters as follows: 
MQHCONN  Hconn;     /* Connection handle */
MQXWD    WaitDesc;  /* Wait descriptor */
MQLONG   CompCode;  /* Completion code */
MQLONG   Reason;    /* Reason code qualifying CompCode */


System/390 assembler invocation

         CALL MQXWAIT,(HCONN,WAITDESC,COMPCODE,REASON)
Declare the parameters as follows: 
HCONN     DS       F  Connection handle
WAITDESC  CMQXWDA  ,  Wait descriptor
COMPCODE  DS       F  Completion code
REASON    DS       F  Reason code qualifying COMPCODE