In <listserv%201001280858249055.0...@bama.ua.edu>, on 01/28/2010 at 08:58 AM, Paul Gilmartin <paulgboul...@aim.com> said:
>My naive understanding of the OS/360 multiprocessing ITYM multiprogramming. >paradigm is that when one unit of work WAITs, another >is dispatched. How does CICS manage to subvert this? It doesn't, any more than JES2 does. What you're missing is that CICS dispatches multiple transactions within a single z/OS unit of work, just like the JES2 main task does. >What happens when a CICS transaction must do something >like: > Invalid PIN number; please re-enter The transaction uses CICS services, and CICS (not z/OS) suspends the transaction until the input is available. >Well, there's nonblocking I/O. But what do you do if the >pipe isn't ready? You let CICS handle the I/O in a separate task and the wait doesn't cause any problems. -- Shmuel (Seymour J.) Metz, SysProg and JOAT ISO position; see <http://patriot.net/~shmuel/resume/brief.html> We don't care. We don't have to care, we're Congress. (S877: The Shut up and Eat Your spam act of 2003) ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html