> I am not aware of any language construct that allows for a DD name to be > randomly selected in a program
Do you mean in COBOL? I am not sure what you mean by "randomly selected" but if you mean "dynamically-constructed" and you are not limiting it to COBOL, then it is certainly trivial and common in assembler to move a dynamically constructed name into DCBDDNAM before the OPEN. COBOL 6 has an interesting thing in that for SELECT local-name ASSIGN external-name that external-name can be the name of an environment variable that contains DSN(dataset.name) disp SPACE(space) etc. I do not know if it is possible to set an environment variable directly from COBOL, but you could certainly call out to a routine that did so. That would pretty much qualify as dynamic allocation from a COBOL program (without calling out to BPXWDYN or similar). Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Lizette Koehler Sent: Wednesday, December 30, 2020 12:56 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Using symbolic DD names So the question becomes, can your Program handle a constantly changing DD Name? What would be the benefit from doing this? In Cobol you predefine (If I am allowed to use this word) the IO Section. Which specifies the DD name - consider that hard coded. I am not aware of any language construct that allows for a DD name to be randomly selected in a program. On z/OS I would be interested if anyone has an example. And yes Scheduling products can supply symbolics where native z/OS might now. Could you provide an example where your program when it executes would use a random DD name in JCL? Lizette -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Billy Ashton Sent: Wednesday, December 30, 2020 12:22 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Using symbolic DD names Hey folks! I have a vendor product program that looks for different DDnames depending on the control statements passed into the program. Is there any way to define a dynamic DD statement using JCL symbols? For example, I would love to have //TB&tno.DAT to correspond to TB01DAT, TB14DAT, or TB67DAT if I use SET TNO=01 or 14 or 67. Is such a thing possible? I tried using an instream proc definition and INCLUDE MEMBER= that proc name, but that failed, and of course, I tried the straight up JCL as above, and it failed. What do you all think? Billy ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
