Need to know how many volumes to allocate was Re: CICS and COBOL reentrancy was Re: F

On Thu, 16 Nov 2006 10:14:55 +0000 (UTC), docdwarf@panix.com () wrote:

>In article <FUT6h.281639$QZ1.108530@bgtnsc04-news.ops.worldnet.att.net>,
>Arnold Trembley  <arnold.trembley@worldnet.att.net> wrote:
>
>[snip]
> 
>
>Unless, I believe, one is going to tape/cart, in which case space
>allocation is unnecessary.  Having to know how many units to allocate for
>the output run of a new program has, at times, been a... challenge; it is
>at the core of the Zen of Programming question of 'How large is an output
>dataset?'

Actually, z/OS allocation is even more arcane.  If your file is going
to go over 5 volumes (tape reels, etc.) on tape or virtual tape you
need to specify a volume count.  Disk allocation may require a volume
count as well as space allocation in either bytes, megabytes,
cylinders or records of some average size.  VSAM has its own
interesting arcanities.  Systems Managed Storage can be used by an
installation to shield the programmers from much of this but a lot of
the confusing parts still are there.
>
>DD