Hello Bernd, if you compile the COBOL Program with Option LIST you can see clear Assembler which can help you.
Best regards Alfred Am 24.04.2013 um 17:22 schrieb "Bernd Oppolzer" <[email protected]>: > My COBOL experience dates from the mid 80s, but > > - I would suggest to always use signed values with comp-3 (packed), and to > mark values as positive, that have no explicit sign information > > And some questions: > > - is it possible today to have comp-3 values in COBOL, that have no sign > nibble? > In PL/1, for example, it is NOT possible to do this ... you have the UNSIGNED > attribute > only for BIN FIXED numeric data, not (yet) for DEC FIXED (CP et al. cannot > handle > unsigned decimal data). > > - if so, the generated CLC which compares such packed fields without sign > nibbles > with fields which have sign nibbles would yield very strange results ... > > - I believe that you must make sure that CPs are generated for such > comparisons, > because it's always possible that you get F sign nibbles instead of C for > positive > signs (after PACK), and they should compare OK - and only CP tolerates > different > sign nibbles > > Kind regards > > Bernd > > > > Am 24.04.2013 16:43, schrieb Phil Smith: >> Suppose you have values that you're converting between character and packed >> decimal, in both directions at various times. You're a middleman, so you >> don't know what the application is going to be using the values for. >> >> For a non-negative value, packed decimal could be either positive or >> unsigned. >> >> What do folks usually do? Is it normal for code to actually care? That is, >> if we say "Heck with it, we can't tell, so we'll just mark it positive", is >> that likely to cause problems? Or is use of unsigned rare enough that this >> is essentially a non-issue? (Hint: I'd like that last to be the case!) >> Obviously a "sign=" value could be passed around with the value, but that >> kind of metadata isn't in the stream now, so I'd rather not add it. >> >> Any and all ideas gratefully accepted... >> >> ...phsiii >> >> >> >> ---------------------------------------------------------------------- >> 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 > > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
