Sometimes we jokingly ask, “how hard can it be?” Don’t be complacent: even the simplest things can go wrong.
Early in my career as a software engineer, I worked on IBM System 360/370 mainframes programming customisations for the MVS operating system in assembler language.
Assembler language is not recommended for the faint of heart – […]
https://dave.moskovitz.co.nz/2024/06/23/even-the-simplest-things-can-go-wrong/
And of course #TSOE - with #ISPF. The TSO commands however look still very familiar. Same with procedures/modules in SYS1.PROCLIB, even with the #IEFBR14 "do nothing" program still very useful in #JCL.
The University of Konstanz still had a #Comparex IBM compatible mainframe running, and I wrote a better version of the existing IRC client in REXX. I added the file transfer functions and fixed the EBCDIC-ASCII conversion. Those were the times.
@[email protected] I think the concept of a link register is older than #RISC and might even predate stack. Mainframe processors use it too and the utility program that "does nothing" is called just "branch to the link register (R14)" https://en.m.wikipedia.org/wiki/IEFBR14 #IEFBR14
I think this program is something like the ":" command in the Bourne family of UNIX shells.
Dave Moskovitz
TheCityDweller 
Marcin Cieślak