On Fri, 27 Aug 2021 10:43:31 -0700, Charles Mills wrote: >MVS provides no such serialization. > >A GLOBAL=YES object "just is." It could be entered any way one chose: BALR, or >LINK, or ATTACH, or its data could be referenced with L and MVC. > >Here is the problem @Peter is referring to: once you make the code available >"globally" there is no general, supported way to put the toothpaste back into >the tube. You never know when some task is going to call the code, and >frankly, you don't know but what some task has called the code and halfway >through using it has become "not dispatched" but might wake up at any time and >continue using it. > If all callers access the GLOBAL module using LINK or ATTACH, CSV should be able to maintain use count and clean up when it reaches 0.
The BALR hazard exists even in the simple, non-GLOBAL case. A programmer must not cause an object to be fetched with LINK then BALR to it in a concurrent thread. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
