On Sat, 5 May 2018 13:45:45 -0500, Mike Schwab wrote: >IBM did a one test library addition for PDSE for COBOL 5 > Details (or citation)? Is this a facility peculiar to COBOL? PDSE only, or old-fashioned PDS?
>On Sat, May 5, 2018 at 10:01 AM, Dan D wrote: >> A very long time ago (over 30 years ago) I worked for a service bureau.\ >> They had specific naming standards for their libraries when products were >> installed (ie. SYSx.product.V01R03.LOADLIB). >> >> We couldn't have our customers continually changing JCL unless they wanted a >> different version than what was installed so we created a system tool called >> "Virtual Dataset Names". >> >> This worked very similar to how ALIAS names works although there was no >> "must be in the same catalog" restriction. >> >> When the system was IPL'd (or later via a special operator command) a table >> was loaded into CSA that contained the REAL dataset name, the VIRTUAL name >> and the various versions that were available. One of the versions was >> marked as the default. >> We used the IGG026DU catalog front-end exit (which I believe is now used by >> DFSMSHSM) to intercept catalog lookups and replace the REAL name that is >> being located with the VIRTUAL name. It would scan SWA and check if an >> ACCT= was specified on the EXEC statement. If so, the 1st operand was used >> to overriding VERION for all datasets within that step. >> Example: >> //step50 exec pgm=iefbr15,ACCT=V5R3 >> //DD1 dd dsn=sys1.sortlib,disp=shr >> If SYS1.SORTLIB is in the table and it's virtual name is PROD.?.SORTLIB and >> it had a list of versions, V1R0 being the alias, DD1 would be translated to >> PROD.V5R3.SORTLIB as ACCT=V5R3 was specified. If it wasn't DD1 would be >> PROD.V1R0.SORTLIB. >> >> Our customers loved this as they could test NEW versions of products before >> they became the default. >> >> If someone has the time, maybe they could take on this project and re-write >> this cool tool ;-) -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
