On Tue, 21 Apr 2015 11:00:20 +0300, Steff Gladstone wrote: >how >does the operating systen itself maintain a continuous ENQ over several job >steps for a dataset allocated in the first step with disp=(mod,pass)?
It isn't so much a question of "How" as "Who". The Initiator performs the ENQ and ATTACHes the Job Step TCB. When the job step ends, it ATTACHes the Job Step TCB for the next step. When the last step ends, it cleans up. Lots of fancy error recovery code is also involved. You said that your process has to be multiple job steps, but if you had a main program that called (or attached) the other programs that need to run to perform the process, you could do the same thing, with an ENQ that covered the whole process. Any necessary allocation and deallocation could be done by the main program. You have also not said how you plan to ensure that other processes do not change the program. What is to stop me from compiling and binding the program outside of your process? Or using IEBCOPY? The ENQ will not do it. These programs will not issue an ENQ against your resource name. There is nothing magic about ENQ. It only works if all of the users of the resource, in this case the program, issue an ENQ against the same resource name. -- Tom Marchant ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
