On Thu, 13 Feb 2014 12:10:54 +0000, DASDBILL2 wrote: >If you are allocating such a data set with disposition=new, the request will >fail if there is not at least one available (Format 0) DSCB in the VTOC which >z/OS can change into a Format 1 DSCB in which to save all the information >about your new data set that occupies no real space. At least the data set >name of this unreal data set will need to be saved. > I raised this question here several years ago. A reader who had the needed privileges (I haven't) got curious and tried the test. He reported that the allocation succeeded even when there were no cylinder extents available.
>If you really wanted to, you could initialize a new volume with a gazillion >cylinders of space and a VTOC of some reasonable size, say 1 cylinder, and >then completely fill the VTOC with Format 1 DSCBs for new data sets, all of >which have 0 space. And then the VTOC would be full and no new data set of >any size could be allocated on this volume which would have a gazillion minus >one cylinders of free space on it. > >This sounds like something that should be tested to make sure it would work >this way. > I don't know that he tested with no available DSCBs; I'd expect that to fail. I can't think of suitable keywords to search the archives. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
