Restrictions

The sending and receiving members must be active members of the same XCF group.
When invoked from an address space resource manager such as the MASTER address space, some IXCMSGOX functions might not be available. Any request that requires the use of one of the member data spaces that XCF manages on behalf of the member is subject to rejection. XCF attempts to perform the requested function without use of these data spaces. If a member data space is required, the request is rejected. Do not use the following keywords if your application cannot tolerate such rejections: SENDTO(GROUP), GETRESPONSE(YES), NOTIFY(YES), or TIMEOUT.
When MSGACCESS=ASYNC or MSGACCESS=SYNCSUSPEND is specified, if the sending member's associated task or address space or both is undergoing termination, XCF will not be able to asynchronously access the sender's data areas. (See the MEMASSOC keyword on the IXCJOIN service.) Thus, an IXCMSGOX request issued from the sender's task or address space resource manager termination routine that completes with return code X'4', reason code X'410' will not be able to successfully complete the send of the message.
When MSGACCESS=ASYNC or MSGACCESS=SYNCSUSPEND is specified, the storage indicated by MSGBUF is subject to the following restrictions:
- If the storage is in the caller's primary address space and this space is not the same space that was primary when the sending member joined its XCF group (that is, the joiner's address space), the caller's primary address space must be non-swappable.
- If the storage is in a data space accessible via a public entry on the caller's DU-AL, the data space must either be owned by the joiner's address space, or be owned by a non-swappable address space, or be a common area data space.
- If the storage is in an address space accessible via a public entry on the caller's DU-AL, that address space must either be the joiner's address space or be a non-swappable address space.
Also when MSGACCESS=ASYNC or MSGACCESS=SYNCSUSPEND is specified, the Dispatchable Unit Access List (DU-AL) under which the caller is running must adhere to the following restrictions. The DU-AL must never have had access to a subspace, must never have had access to more than 255 spaces of any kind at one time, and must not be full. If the message-out service is unable to process the request because the DU-AL is unsuitable, the IXCMSGOX request is rejected with return code X'C' and an appropriate reason code.
When MSGACCESS=SYNCSUSPEND is specified, the following environmental restrictions apply:
- The XCF message-out request cannot be issued from a SUSPEND exit routine or from an SRB routine that the system abended with a 47B system completion code.
- The XCF message-out request using MSGACCESS=SYNCSUSPEND cannot be issued from an address space resource manager. An IXCMSGOX request issued from an address space resource manager termination routine completes with return code X'8'', reason code X'354'.