Paul, I think you meant to say that "thus no need to clear it other than (immediately) after WAIT".
If you clear it before WAIT, you could well be clearing out the POST bit, which means you could WAIT forever. Tom Harper Neon Enterprise Software, Inc. -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Paul Gilmartin Sent: Wednesday, January 23, 2008 11:31 AM To: [email protected] Subject: Re: How does ATTACH pass address of ECB to child? (1 On Wed, 23 Jan 2008 07:53:42 -0800, Edward Jaffe wrote: > >I agree that WAIT/POST -- a service that's been around since OS/360 -- >seems simple enough on the surface. But, look how many people on >IBM-MAIN are still exhibiting confusion regarding its use -- even about >something as fundamental as how/when to clear the ECB! This observation >seems to support Chris Craddock's assertion that, even after more than >40 years, the documentation is still quite lacking. > I suppose the assertion can be further supported by failure to exhibit such documentation. Until this thread, I had envisioned no use of the ECB except by WAIT and POST; thus no need to clear it other than (immediately) before WAIT. You and Peter R. have demonstrated otherwise. BTW, do the contents of the ECB other than the WAIT and POST bits matter to WAIT? IOW, instead of "XC ECB,ECB" (or CS) would it suffice to do as little as "MVI ECB,x'3F'", or would it disrupt the fabric of the universe? (Don't ask "why"; mere scientific interest.) -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
