Mark,
See:
? ?
Note the last three manuals on that page ... Vol. 1 is for CP, Vol. 2 is for CMS ... Vol. 3 is for RSCS etc.
SVC 202 and 203 are for CMS ... and are defined or described on page 2-7 of that Vol. 2 manual:
?
There are overlapping SVC numbers between CP and CMS, because the CP ones only matter when you are running inside CP ... some DMKxxx modules;? CMS is running in a virtual machine (the DMSxxx modules) and has its own "set" of SVC numbers.? ?CMS also supports OS simulation so many SVC numbers come from OS/360 MVT ... to allow those OS compilers etc. to run under CMS.? ?
If you "SET DOS ON" in CMS, that swaps in a different SVC table, to emulate DOS/VS SVC numbers.
Hope that helps,
Mark S. Waterbury
