Callbacks and reply solicitation calls can be used to retrieve
replies from asynchronous ECI requests
Callbacks
Callbacks enable the CICS® server to drive specific function provided by the user
application when an asynchronous program link call completes. Callbacks
are not available for all APIs.
Reply solicitation calls
User applications that issue asynchronous calls can have several
ECI requests outstanding at a time. Reply solicitation calls can be
used by the calling application to retrieve the replies for each outstanding
request. There are two types of reply solicitation call:
- General
- Retrieves all replies for any outstanding ECI request.
- Specific
- Retrieves a reply for a specific ECI request. A unique message
qualifier is used to identify the reply for that request. Depending
on the API that the application uses, message qualifiers are either
automatically generated or a they have to be manually assigned to
each asynchronous call within a single application.
If no reply is available, reply solicitation calls
can either wait for a reply or return control directly to the user
application.