At least in z/OS 2.5 TSO/E... As I said in the previous post, the null or blank line *inside* ENDDATA is because that's how this particular command (LINK) knows to stop asking for input control cards. It needs to be in the DATA PROMPT-ENDDATA sequence so it is sent to LINK.
The null after ENDDATA is something else. I asked an AI, and the explanation was that this is a CLIST safeguard. The problem is that sometimes a TSO command doesn't clearly signal to TSO/E that it is done with the buffer. Putting a null line in "forces a blank entry directly into the TSO/E input stream right after the block closes", which enables control to be returned to the CLIST. Sounds like black magic to me. Maybe long ago a null line after ENDDATA would actually close commands like LINK in this situation, but TSO/E has changed so it needs to be inside. And, I am **NOT** a CLIST fan. CLIST is an evil genie. -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Rupert Reynolds Sent: Wednesday, June 3, 2026 4:02 PM To: [email protected] Subject: Re: Any CLIST fans still here? I can't make DATA PROMPT work Interesting. I'd always assumed that ENDDATA gave the same effective EOF as the null line. But the IBM example goes to the trouble of "SET NULL =" and yet it codes &NULL after the ENDDATA, while I'd expect to see it before, if anywhere. I think I may simply have an old version of the LINK command! -- Roops "Mundus sine caesaribus" ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
