Path: utzoo!utgpu!water!watmath!clyde!rutgers!husc6!bbn!uwmcsd1!ig!jade!ucbvax!CLVM.BITNET!VALDIS
From: VALDIS@CLVM.BITNET (Valdis Kletnieks)
Newsgroups: comp.lang.asm370
Subject: Finding buffer images from LOADBUF command
Message-ID: <8712181657.AA11158@jade.berkeley.edu>
Date: 18 Dec 87 15:57:40 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: IBM 370 Assembly Programming Discussion List <ASM370%UCF1VM.bitnet@jade.berkeley.edu>
Distribution: inet
Organization: The ARPA Internet
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Here's how you find the FCB -

(1) Find the RDEVBLOK for the printer
(2) RDEVEXTN (RDEVBLOK+x'34') points at the RSPXBLOK
(3) RSPXFCB  (RSPXBLOK+x'0C') has the FCB name in it.

You can then rummage thru DMKFCB to find the FCB image.  Look at
the FCB macro to see how they are chained up.

The UCS is a bit harder, as it is only saved in one spot - UCSNAME
in the IOBLOK for the command.  Unfortunately, IOBLOKs are transitory things,
so unless you know the LOADBUF command is CURRENTLY processing, you're
out of luck.  If you HAVE to know it at an arbitrary time, I'd
extend the RSPXBLOK by 4 bytes (modify RBLOKS COPY), reassemble DMKMNT
so it allocates a bigger RSPXBLOK when the system IPL's, and then mod
DMKCSB to save the data there as well as in the IOBLOK.

If this doesn't answer your questions, let me know...

                                   Valdis Kletnieks
                                   Systems Programmer
                                   Clarkson University