Ed, thanks! > This is supported on z/VSE.
I remember that. DOS/360 was my first "get down and dirty" operating system. I was surprised that you could not do this when I made the big move to OS. The tradeoff is that at least at that time the DOS dispatcher had to go through a very large loop every time a POST type event happened, because waiting tasks were not chained to the relevant ECB in any way. Of course, DOS only supported a maximum of nine (?) tasks. > a similar (but opposite) issue exists for not being able to wait on multiple events with IEAVPSE I forgot to mention IEAVPSE/IEAVRLS among the possible candidates for this function. They don't allow it either, unfortunately. At least the doc is abundantly clear (even if they do mis-use "then" for "than"): "A PE can be used to pause only one task at a time; the system does not allow more then one dispatchable unit to be paused under a single PE." > There is no support in z/OS for what you want. Phooey! Seems to me that this would have been an awfully useful thing to have included in the OS, and that it would not have been all that hard to chain all of the waiting TCBs together. The designers might have included the restriction that you get *either* ECBLIST *or* multiple tasks, not both; that tasks and ECBs are either 1:n or n:1 but never m:n. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Edward Jaffe Sent: Saturday, May 05, 2012 9:03 AM To: [email protected] Subject: Re: Multiple waiting tasks, one control block? On 5/5/2012 8:43 AM, Charles Mills wrote: > I have a situation in which it would be a wonderful thing if I could > have multiple tasks waiting for a single event, without having a > separate "wait control block" of some sort for each task. This is supported on z/VSE. > Why? I have no control over what the tasks "have" in advance (system > exit > situation) and doing a GETMAIN or the like so that each task could > have its own ECB, and then chaining them all together, following the > chain with POSTs, FREEMAINs, etc., etc., would be a real pain, a lot > of overhead, and a real risk of mucking it up. > > I know WAIT/POST/ECB does not support multiple tasks waiting on a > single ECB. > > I guess that EVENTS does not support this either -- but I don't see it > explicitly in the documentation -- is my assumption correct? There is no support in z/OS for what you want. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
