Mainframe, MVS and zOS Discussion

What CICS facilities does USER_PROG use?

COBOL CALL statements by default pass values by reference. Hence, the first value passed will be assumed by CICS to be DFHEIBLK and the second DFHCOMMAREA. If you omit these two parameters from your code, at best CICS is going to be updating fields in your user data as if it were DFHEIBLK; at worst, you could bring down the entire CICS region.

nicc wrote: What CICS facilities does USER_PROG use?

That's a simple CICS inquiery screen program.

Robert Sample wrote: COBOL CALL statements by default pass values by reference. Hence, the first value passed will be assumed by CICS to be DFHEIBLK and the second DFHCOMMAREA. If you omit these two parameters from your code, at best CICS is going to be updating fields in your user data as if it were DFHEIBLK; at worst, you could bring down the entire CICS region.

Thanks! Entire CICS can be down just by a program..?

Easily - I have seen it happen plenty of times.

[ Post made via iPhone ]

Update: many years ago I was a contractor. The client programming manager and a fellow contractor got into an argument about whether or not the 32K limit on DFHCOMMAREA still existed. The programming manager said he'd show us the limit was gone and compiled a program with a 128K DFHCOMMAREA. After he did the newcopy and entered the transaction id that invoked the program, all over the room programmers started yelling "Test CICS just went down".