On Tue, May 5, 2015 at 7:29 AM, Paul Gilmartin < [email protected]> wrote:
> On Mon, 4 May 2015 20:51:47 -0400, Shmuel Metz (Seymour J.) wrote: > > > >>if DSN is migrated > > > >The OP wrote "non-existent", not migrated. The message is appropriate > >for a new DASD dataset with no SPACE specification. > > > But it's inappropriate that the OS create a new data set when it knows > that it will be deleted immediately, never used. > Is it "inappropriate"? Suppose, just for the sake of argument, that I am an clever JCL coder. I know that all the NEW allocations for permanent data sets in the job will amount to some number of cylinders. Now, I don't want the job to fail some steps into the job due to lack of disk space. So what I do is create a initial IEFBR14 step which allocates some number of permanent DSNs of appropriate size with DISP=(NEW,DELETE). What I am hoping is that if sufficient space is _NOT_ available, that I will get a JCL error very early in the processing, rather than later. Yes, granted, I am not not _assured_ that just because the space is available at the start that it will stay available for the duration of the entire job, but I have at least _tried_ to to be "pro-activate" about disk space. One reason might be that the shop, as this one has been in the past, barely has enough disk space to get by on. I guess, in this case, it would be more clever to use DISP=(NEW,PASS) to allocate the data sets & pass them on. That way, should one or more steps not run due to COND codes, the associate data sets for that step will not be catalogued (said step using DISP=(OLD,CATALOG,DELETE) for example). OK, I will admit that the above is a poorly contrived example of one reason to not bypass allocation just because the PGM= is IEFBR14. Another reason could be the amount of special coding required to support the "don't allocate". If we are going on in that vein, then why even have the initiator bother to run IEFBR14? Why not just have the initiator code ignore the IEFBR14 step entirely and post the step as "ran successfully with RC=0"? Being the way that I am, I don't really like a bunch of (IMO) _unnecessary_ special coding > > -- gil > > -- If someone tell you that nothing is impossible: Ask him to dribble a football. He's about as useful as a wax frying pan. 10 to the 12th power microphones = 1 Megaphone Maranatha! <>< John McKown ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
