Why and how COBOL is still used

Re:Why and how COBOL is still used by tyingq on Monday November 15, 2021 @02:47PM (#29231771)

For the most part, it's not the COBOL itself that makes it hard to port. It's the features of the surrounding OS for things like screen layouts, batch process management (not cron like, but deep job dependencies, etc), database management, file transfer, user management, etc. So to port the app, you have to know quite a lot about what things like RACF, TSO, CICS, JCL, Tivoli, Adabase/IDMS/etc, are contributing to the overall app. Porting the COBOL is sometimes not even half the effort.

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Re:Why and how COBOL is still used by prajwalshetty on Monday November 15, 2021 @05:43PM (#29233906)

True, I started as a COBOL programmer (did a lot of TELON online screens, JCL, CICS, DB2...) as my first job in 2009, for a biggest retailer - personally it taught me a great deal of software engineering - having a background in electronics engineering helped I guess.

The whole stack, and the complex business built around it over many years makes it so difficult for these large institutions to port their solutions on to a new platform in my experience too.

For a lot of these companies, these backend systems on Mainframes just works and I believe there isn't a proper incentive to move on to a new platform anyway.

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Re:Why and how COBOL is still used by partomniscient on Monday November 15, 2021 @10:31PM (#29236443)

There's DB2, and then there's IMS-DB/DC...

COBOL itself isn't too difficult to pick up, its the rest of the infrastructure around it. JCL is particularly unforgiving. I'm in total agreement with the parent post of this thread.

I think the thing that bugged me the most about COBOL is the difference between END-IF. and END-IF

Everything else was onerous compared to other languages but relatively straightforward. It's not something to get a simple job done quickly in though.

The simplicity created by things largely remaining the same over time in mainframe world is one of its core strengths.

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Re:Why and how COBOL is still used by mrjin on Tuesday November 16, 2021 @04:45AM (#29238701)

People tend to think migrating an application is all about rewriting the program itself. But actually rewriting is only a small fragment of efforts needed. For some large organizations the legacy code base is so large that it would be crazy to rewrite them in a different language in the first place. This does not event mention the effort to test or validate if the new application works as expected. Put those thing aside, building a new infrastructure with PC servers and hire/retrain the operations would almost much larger than anticipated by most of the people. After evaluating all the options, scale up/out with MFs would be the cheapest and most reliable solution to provide more capacity for a perfectly working application. IBM has done a decent job on keeping MF backward compatible. There are lots of core banking systems running S360 Assembly applications on latest MFs today, in comparison, COBOL is not that old at all.

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