It depends on how backleveled your customers are (might be), and how will your products react to an 0C1?
This code is a few years old, but shows how you can detect PLO's availability. The SMTHUPLO bit (in a private control structure) provided an external means of forcing the code through its alternate path (which uses a spin lock) for testing: > PUSH USING Save current USING status > L R1,CVTPTR Get address of CVT > USING CVTMAP,R1 Map Comm. Vector Table > ICM R2,15,CVTSCPIN Get address of SCCB > SCCB present on this sys? > BZ Init020 No ==> Assume no PLO > USING SCCB,R2 Map Service Call Ctrl Blk > TM SCCBCON4,SCCBPLO PLO instruction available? > BZ Init020 No ==> Go turn off in SMT > TM SMTHOPT3,SMTHUPLO PLO use disabled in SMT? > BZ Init030 Yes ==> Go on to next step > OI SmwaFlag1,SmwaF1Plo Show PLO facility av'able > B Init030 ==> Go on to next step >Init020 DS 0H > NI SMTHOPT3,255-SMTHUPLO Show PLO =not= available > POP USING Restore prev. USING state Art Celestini At 12:37 PM 5/27/2005, Jeffrey D. Smith wrote: >Greetings, > >I am wondering what is the oldest machine that supports >the PLO (Perform Locked Operation) instruction, and whether >there are any older machines that are still running supported >versions of MVS (aka OS/390, z/OS)? > >Phrased another way, is it safe to write commercial applications >(targeted for any IBM-supported version of MVS) that require the >presence of PLO? > > > > > ================================================== Art Celestini Celestini Development Services Phone: 201-670-1674 Wyckoff, NJ ============= http://celestini.com ============= Mail sent to the "From" address used in this post will be rejected by our server. Please send off- list email to: ibmmain<at-sign>celestini<dot>com. ================================================== ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
