Steve Comstock wrote: >Also, what about the shop that tries to locate the end date and zap it? You >may say it doesn't happen but I have heard tales...
True. I also heard it via grapevine. Some software does integrity checks [CRC check?] on that date to prevent zapping. Rather, you can replace [1] a jump/branch to that part which examines that date, so no checking can be done at all. However, that will also fails if the checking part sets [sometimes periodically] a flag in memory which says "I'm now licensed/legal" and each functions of that software check that flag. There are self modifying code [on PC] which modifies the storage areas where the program is loaded and then in that storage the keys/dates/etc are only revealed/checked. So what is written in the program on disk is not always the same when loaded in memory. I think that self modifying trick can't be done with REUS=RENT programs except those in key=0 on z/OS. [2] Groete / Greetings Elardus Engelbrecht [1] - with some NOPs. [2] - debuggers can override it, even with REFRPROT set. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
