I apologize. Other things got in the way and I have not yet done this. I recognize the great possibility of "false negatives": two load modules could be functionally identical but checksum differently.
One might even quibble about the meaning of "functionally identical": if one load module does LHI R0,0 and another does LA R0,0 are they functionally identical? Most people would say they were, but obviously a checksum program would (or should!) disagree. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Seymour J Metz Sent: Thursday, April 28, 2022 5:23 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Checksum of "legacy" load module? If you do a COPY then the records, and hence the hash, should be identical. It's COPYMOD that reblocks. I don't know of any utility that will compare only the csect text. Further, two load modules might differ only in the RLD records, and that definitely should be picked up as a change in version. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List [IBM-MAIN@LISTSERV.UA.EDU] on behalf of Mike Schwab [mike.a.sch...@gmail.com] Sent: Wednesday, April 27, 2022 9:06 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Checksum of "legacy" load module? A load module consists of some txt records, where the entry points and external variables are deifined, then a short record followed by a block of binary instruction in a multiple of 1K. During copy / compress / restore of a module, the binary machine code is regrouped into different sized blocks that are multiple of 1K to fit into the space available on that track (which is highly variable based on the earlier contents of that load module library, and between the multiple of 1K machine code blocks is a short block. So if you ignore the small blocks, and ignore the record boundaries of the big blocks, that portion should be identical. Then you might see some differences in the TXT records at the start or in the binary machine code. (order of TXT item, time stamps, PTF levels), On Thu, Apr 28, 2022 at 12:15 AM Seymour J Metz <sme...@gmu.edu> wrote: > > Is the output of an IEBCOPY COPYMOD equal to the input? The results of loading them into storage are the same, but the won't have the same hash. > > > -- > Shmuel (Seymour J.) Metz > http://mason.gmu.edu/~smetz3 > > ________________________________________ > From: IBM Mainframe Discussion List [IBM-MAIN@LISTSERV.UA.EDU] on behalf of Paul Gilmartin [0000000433f07816-dmarc-requ...@listserv.ua.edu] > Sent: Tuesday, April 26, 2022 6:54 PM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Re: Checksum of "legacy" load module? > > On Tue, 26 Apr 2022 15:30:29 -0700, Charles Mills wrote: > > > >Specifically what I am trying to do is answer the question "is load module X > >in PDS Y.Z on box A binary equal to load module X in PDS Y.Z on box B?" > >without copying and comparing. I suspect the BLKSIZEs are the same so that > >may make the task easier (or prevent false negatives). > > > I once suggested that a co-worker with a similar requirement compare > AMBLIST outputs. AMBLIST? She had a rapid "Aha!' moment" > displacements differed -- macro level inconsistecy. > > Checksum of TSO TRANSMIT output? Bind into zFS program objects > and cksum? > > Regardless, timestamps and headers are apt to bite you. > > Nostalgia: I recall a Mac OS (ISV?) utility that compared two > APPLs and generated a patch file. > > -- > gil > > ---------------------------------------------------------------------- > 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 -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- 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