Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!draper.COM!SEB1525 From: SEB1525@draper.COM ("Steve Bacher ", Batchman) Newsgroups: comp.lang.asm370 Subject: RE: opsyn opcode in ibm bal Message-ID: <8906072305.AA29483@jade.berkeley.edu> Date: 7 Jun 89 11:46:00 GMT Sender: daemon@ucbvax.BERKELEY.EDU Reply-To: IBM 370 Assembly Programming Discussion List Distribution: inet Organization: The Internet Lines: 7 I've seen OPSYN used by at least one software vendor in a module that is designed to assemble into a list of control block offsets. It does this by using OPSYN to redefine the DC and DS opcodes as macros and then calling out an MVS control block mapping macro. Each DC or DS in the MVS macro is then processed by the vendor macro, which is able to do its thing because the offset of each MVS field (which varies with software releases, maintenance, etc.) is known at that point. That's the only use I know of.