> -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:ibm-m...@bama.ua.edu] On Behalf Of Frank Swarbrick > Sent: Thursday, June 24, 2010 1:00 PM > To: IBM-MAIN@bama.ua.edu > Subject: instream data > > Now that we've been on z/OS for a few weeks I feel to need to > ask a question that has annoyed me since I started working on > z/OS two years ago. Instream datasets are good. Why are > they not supported inside of procs? Is there a technical > reason, or is it just "because"? We use procs for almost all > of our production jobs, with many steps that could take > advantage of instream datasets if not for this restriction. > > Thanks, > Frank > > -- > > Frank Swarbrick
That has been a restriction since the dawn of OS/360. In that case, I think it was due to the primitive nature of the reader code. IIRC, the original reader code (pre HASP), read cards from the card reader. When it detected in-stream data, it actually created an "temporary" OS dataset and wrote the cards into that dataset. The processing of PROCs (expansion) was done in another part of the code, not in the actual reader. So, to have "in stream" data would require a more complicated and advanced expansion. And that was not really possible at the time. To the best of my limited knowledge, JES2 still sort of works this way. JCL is read in and written to the job's JESJCL SPOOL dataset. Instream data causes the allocation of a separate SPOOL dataset, with the data being written to it. When th end of the instream data is detected, this "sysin" SPOOL dataset is close and JES resumes writing the JCL images to the JESJCL SPOOL dataset. Once the job is totally read in, JES2 invokes a z/OS supplied routine to convert the JCL to internal text. If instream data were allowed in a PROC, this converter would need to know how to process it and create/write it to the a new JES SPOOL dataset. Which it does not know how to do. IIRC, JES passes parameters to the converter so that it can read the JESJCL SPOOL dataset and write to the $INTTEXT SPOOL dataset. But the converter does not have an interface create and write to a "new" sysin type SPOOL dataset. Of course, that is not really a good reason to continue to have this restriction, IMO. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets(r) 9151 Boulevard 26 * N. Richland Hills * TX 76010 (817) 255-3225 phone * (817)-961-6183 cell john.mck...@healthmarkets.com * www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
