IBM did a one test library addition for PDSE for COBOL 5 On Sat, May 5, 2018 at 10:01 AM, Dan D <[email protected]> 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 ;-) > > Dan > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN
-- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
