RDJFCB! Right! Thank you. I recall there's also the C library svc99() and BPXWDYN INFO but not sure they fulfill the requirement of "simpler." Also EXLST and catching the ABEND. Don't get me wrong -- I've used them and they're not awful -- but there is a lot there relative to mapping an 8-byte string onto is/is not DUMMY.
I'm doing the OPEN anyway so RDJFCB should be a short leap. I can live with the same information for a UNIX file. I am trying to disqualify "this is not a reasonable load library" and so that is fine. Thanks, Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of John McKown Sent: Tuesday, February 19, 2019 7:39 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Any easier way to determine if DD is dummy than GETDSAB? On Tue, Feb 19, 2019 at 9:20 AM Charles Mills <charl...@mcn.org> wrote: > I've got a requirement to determine whether a DD is allocated DUMMY. I know > how to find the TIOT, get the JFCB with SWAREQ, check for 'NULLFILE' and > loop through all of the JFCB chain. Is there any easier way? That's a lot > of > complexity for a simple question! > > Why? I'm trying to avoid an S013-64 on a BPAM file if the user does not > supply a DSN to a PROC. I'm defaulting the DSN to NULLFILE. I'd like to be > able to determine that from my program. > > The program is in IBM C but I can readily call out to assembler. The OPEN > for the BPAM DCB is in assembler, not using the C library. > RDJFCB will also return NULLFILE for a DD DUMMY. Unfortunately, it also returns that for a UNIX PATH= file. https://www.ibm.com/support/knowledgecenter/en/SSLTBW_2.2.0/com.ibm.zos.v2r2.idas300/rdjfcb.htm ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
