GCC COBOL and Mainframe Migration

“Mainframe Migration” generally refers to project trying to move applications and data from IBM mainframes (the IBM z/Series®) to Linux and other “modern” platforms. This is a type of Application Modernization. On that page we discuss, briefly, some of the challenges with the COBOL migration.

Mainframe shops have multiple generations of utility programs, programming languages, and development technologies. Older applications often cause related third-party products to remain in use long after newer technology has been used for newer applications.

CICS

CICS is a very popular online transaction processiong subsystem. Firms have been finding ways to interface more modern User Interface software to CICS. Particularly Web applications. However, the applications processing the transactions under CICS continue to run on the mainframe.

There is a commercial work-alike OpenKicks which has proven to work well with GnuCOBOL>.

JCL/CL (Command and Control Languages)

There are various Open Source and ISV (proprietary) options for converting JCL into native scripts. A few examples from a recent Web search:

VSAM, IMS/DB, and i Series Files

VSAM: Many implementations of VSAM on SQL (Relational Databases) have been done. Quite often they offer adequate function and performance. We know of no Linux-native implementation of fully compatible VSAM.

IMS/DB: This is much like VSAM. Again, many successful implementations of IMS/DB function have been done based on SQL/RDBMS. But none offer the kind of performance and operational compatibility many end-users expect.

COBOLworx has a limited-function prototype of an IMS/DB work-alike we call the Pre-Relational Information Manager (PRIM but it is far from production-ready.

i Series: The file-system on these mid-range machines is quite different. There is a reduced function verions of the DB2 RDBMS for Relational. Otherwise, this is a very gray area.

ISPF and REXX

Both of these popular IBM tools are well represented by Open Source Software work-alike implementations.

Java

IBM has rich support for Java including COBOL Object Oriented Programming integration. Java applications are easy to port to the Cloud but the COBOL/Java OO facilities don’t exist yet on COBOLworx compilers.

Third Party Applications

Many long-term users of IBM systems adopted applications for programming and data management from independent software vendors (ISVs). Some like [SyncSort](https://precisely.com/ and [Software AG](https://softwareag.com/ (NATURAL and ADABAS) are still very much in business and active on both IBM and open platforms. Others were swept up by Computer Associates which then got swept up by [Broadcom](https://broadcom.com/ That inventory is still largely available though not necessarily on Open Platforms.