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How could it know? When RPG performs the call, it passes the specified parameters as space pointers to the first byte of the value - this is called "call by reference". Until ILE, universal program calls did not include any meta-information about the parameter. When the System/38 shipped, we all thought that universal inter-program calls were a miracle. Prior to that, programs written in RPG couldn't call a program written in COBOL or PL/I or C or anything else. On the 36, programs couldn't call each other at all. I think that ILE includes the concept of a self-describing parameter. That is a parameter that contains its length, type, and attributes in a place where all languages can find them. Loading these independent descriptors takes machine cycles that many of us aren't willing to pay. So, if I call your program with the right number of parameters but without the descriptors, your program doesn't know what it is getting. I don't want that to change because I want high-performance calls. I assume (that means that I don't know and I didn't look it up) that you could reject calls from programs without descriptors. That would allow you to protect yourself from doing something wrong but it forces all the caller programs who want to use your program to pay a price. I think what you want is called "SMOP". This is an acronym for "small matter of programming". In other words, you can have anything you want if you or someone else sits down and writes the programs to make it happen. The acronym is also a joke. By saying "small matter ...", it implies that it isn't much programming and there is little design or consequences from it. Sometimes the amount of programming isn't small and it requires a lot of design time and the consequences are huge. But that is why it is funny. The 400 doesn't handle the problem and it won't be free for anyone to do it and the consequences could be large. Richard Jackson mailto:richardjackson@richardjackson.net www.richardjacksonltd.com Voice: 1 (303) 808-8058 Fax: 1 (303) 663-4325 -----Original Message----- From: owner-rpg400-l@midrange.com [mailto:owner-rpg400-l@midrange.com]On Behalf Of Silvio Santos Sent: Wednesday, July 12, 2000 10:20 AM To: RPG400-L@midrange.com Subject: RE: RPG/400 pgm strange behaviour I understood more or less your explanation. Shouldnt the AS/400 pass the pointers in a way to avoid those problems ? Because if the lenghts of the variables are correct either in the calller as in the called it should work ok. Silvio. "Richard Jackson" <richardjackson@richardjackson.net> on 07/12/2000 04:03:14 PM Please respond to RPG400-L@midrange.com To: RPG400-L@midrange.com cc: (bcc: Silvio Santos/VC/PT/BRAIN) Subject: RE: RPG/400 pgm strange behaviour In this case, the parm lengths and definition location in the caller program is the problem. In the RPG program static storage allocation, the MSDT$E field is defined as some length like 33 in the caller program, field $RTC$E is defined immediately after it with a length of at least 6. When this routine is called, the caller passes a space pointer to MSDT$E at some address and the caller also passes a space pointer to field $RTC$E. For this explanation, assume that the location of MSDT$E is decimal 1001 and the location of $RTC$E is decimal 1034. Neither field MSDT$E nor field $RTC$E occupies space in the callee program, they are used by reference. Since it is defined as a *ENTRY parameter, the callee length should match the caller length definition. When they don't match, this is the AS/400 version of a memory leak - you can change memory that doesn't belong to you. I have spent days trying to find these things. I am feeling like this is a very weak explanation of the problem. If you can't figure it out from this poor explanation, please drop me another note. Richard Jackson mailto:richardjackson@richardjackson.net www.richardjacksonltd.com Voice: 1 (303) 808-8058 Fax: 1 (303) 663-4325 -----Original Message----- From: owner-rpg400-l@midrange.com [mailto:owner-rpg400-l@midrange.com]On Behalf Of Silvio Santos Sent: Wednesday, July 12, 2000 5:01 AM To: RPG400-L@midrange.com Subject: RPG/400 pgm strange behaviour I have a program (RPG/400) that checks if some record exists and return. These two filds are *ENTRY parms of the PGM: MSDT$E - length 256 $RTC$E (*FOUND or *ERROR) - length 8A The condition used is like this: *IN,96 IFEQ '0' MOVEL'*FOUND' $RTC$E MOVELMSDTOH MSDT$E ELSE MOVEL'*ERROR' $RTC$E ENDIF It works fine, excepts for one thing: if the condition is true, when it moves the MSDTOH content to MSDT$E, it erases the $RTC$E field. For the other hand, when the first move is done, the '*Found' is placed in the 34th position of the field MSDT$E. Is there any restriction about entry parms lenght ? How can I resolve this? Thanks ,,,,,, (o o) -----------------------oOO--(_)--OOo------------------------ Silvio Santos BRAIN Portugal Tel: +351 252 248-120 Av. Joao Canavarro, 305 Fax: +351 252 248-111 4480-668 Vila do Conde Portugal Email: silvio.santos@brainag.com Web-Page: www.brainag.com --------------------------------------------------------------------- +--- | This is the RPG/400 Mailing List! | To submit a new message, send your mail to RPG400-L@midrange.com. | To subscribe to this list send email to RPG400-L-SUB@midrange.com. | To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: david@midrange.com +--- +--- | This is the RPG/400 Mailing List! | To submit a new message, send your mail to RPG400-L@midrange.com. | To subscribe to this list send email to RPG400-L-SUB@midrange.com. | To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: david@midrange.com +--- ,,,,,, (o o) -----------------------oOO--(_)--OOo------------------------ Silvio Santos BRAIN Portugal Tel: +351 252 248-120 Av. Joao Canavarro, 305 Fax: +351 252 248-111 4480-668 Vila do Conde Portugal Email: silvio.santos@brainag.com Web-Page: www.brainag.com --------------------------------------------------------------------- +--- | This is the RPG/400 Mailing List! | To submit a new message, send your mail to RPG400-L@midrange.com. | To subscribe to this list send email to RPG400-L-SUB@midrange.com. | To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: david@midrange.com +--- +--- | This is the RPG/400 Mailing List! | To submit a new message, send your mail to RPG400-L@midrange.com. | To subscribe to this list send email to RPG400-L-SUB@midrange.com. | To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: david@midrange.com +---
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