Hi John --

iirc the internal PDSE structure is based on VSAM and is not published.  The
usual MVS access methods were updated to ensure compatibility but under the
covers it's totally different.

I looked at accessing them from vm on shared packs a couple of years ago and
unsurprisingly found nothing.  I now access them via ftp instead -- and find
that (usually) I can read from MVS over ip *faster* than vm can write that
same data to minidisk, and that whilst shared packs protect you from an mvs or
ip outage it's so rare that that happens -- unless you're RBS and HP are
managing your systems of course (q.v.) -- that it doesn't compensate for the
problems that arise with having to manage PDSs on non-sms packs.

I would test what speed you can get over ip using the ftp stage on marist
which allows you to ftp records directly into a pipe -- the syntax is rather
non-obvious, but when you get it working it's a gem.

i

------ Original Message ------
Received: 12:47 PM COT, 12/31/2009
From: "Larson, John E." <[email protected]>
To: [email protected]
Subject: Re: Reading MVS PDSE datasets from VM/CMS.

> I have used the OSPDS stage provided on the PIPELINEs library, as well as
the built-in LISTPDS, and various user written stages for processing an MVS
linked DASD to read members from a partitioned dataset.
> 
> But...now we have PDSEs (Partitioned Data Set Extended), and I find that
none of my old pipes and execs work with PDSE.
> I have been doing some reading on PDSEs, and realize that they are organized
quite differently, and the member directory blocks are organized completely
different.
> 
> Does anyone have ANY method of reading an MVS PDSE from VM/CMS??
> 
> John
> 

Reply via email to