On Tue, 4 Apr 2023 21:09:59 +0000, Frank Swarbrick wrote: >How do you set R0 in C? > I suspect it's an undocumented beneficial, whether accidental or deliberate. side effect of TSO CALL or C function call.
>________________________________ >From: Steve Thompson >Sent: Tuesday, April 4, 2023 12:06 PM > >A similar issue happened with BPXWDYN. COBOL can't set R0. So a >new entry point in BPXWDYN was created that handled that problem. > Now I've looked at the TSO/E REXX Ref. It's rife with mention of R0 used to address the ENVBLOCK. Terrible design. (I suspect it came from CMS) They used R0 because no one else used it, oblivious that there's a reason for that. It would have been better design to follow the conventions of the CALL, LINK, and ATTACH macros and add another argument to the R1 PL (after the alternate DDNAME list if any.) -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
