On 13 February 2018 at 07:44, Steff Gladstone <steff.gladst...@gmail.com> wrote: > Or you could check if R14 is pointing to a SVC 3 instruction.
That may or may not work. If you are running under TSO TEST it will point to an SVC 97 instead. > Actually the routine (not written by me) was using the FSA to retrieve the > pointer to the value of the PARM= parameter (saved R1). > Presumably that's a valid use as well. A program has no obligation to save the registers in its caller's save area. So R1 will be saved there only by the grace of the invoked program. Certainly it's the norm, but not strictly "valid". Tony H. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN