> The DCB keeps state. I know that very well, but that wasn't the question. The question was "is name/token create/retrieve better performing than GETMAIN/FREEMAIN (or STORAGE OBTAIN/RELEASE)?"
There are lots of situations where a function might need QSAM in 24-bit storage but not need to save state (save a DCB) across calls: - a function that opened, read, and closed a dataset and "summarized" the results in some way for the caller. - a function that copied one dataset to another. - a function that issued RDJFCB, returning the JFCB to the caller (yes, I know there are other ways to get a JFCB) - in the function that is currently on my plate, the DCB is used with ATTACH and is opened and closed within a single call to the function. - there's another one on my plate in which a DCB is opened and closed within a single call, but it's too complicated and distracting to explain the purpose in an e-mail. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:ibm-m...@bama.ua.edu] On Behalf Of Binyamin Dissen Sent: Monday, February 22, 2010 6:24 AM To: IBM-MAIN@bama.ua.edu Subject: Re: Best practice for 24-bit storage in assembler called from C/C++ On Mon, 22 Feb 2010 06:14:16 -0800 Charles Mills <charl...@mcn.org> wrote: :>> You can anchor in name/token. :>Considering just functions that require a 24-bit work area and do not need :>to preserve state across calls, is name/token create and retrieve going to :>be significantly better performing than FREEMAIN and GETMAIN? :>(A serious question -- I don't know the answer.) The DCB keeps state. :>-----Original Message----- :>From: IBM Mainframe Discussion List [mailto:ibm-m...@bama.ua.edu] On Behalf :>Of Binyamin Dissen :>Sent: Monday, February 22, 2010 12:07 AM :>To: IBM-MAIN@bama.ua.edu :>Subject: Re: Best practice for 24-bit storage in assembler called from C/C++ :>On Sun, 21 Feb 2010 18:00:19 -0800 Charles Mills <charl...@mcn.org> wrote: :>:>I'm writing a fairly large MVS batch application in C++. At several points :>:>it is necessary to call "library" type routines that I am writing in :>:>assembler. Several of the routines (unfortunately) need to use QSAM macros :>:>and so need below-the-line storage. :>:>Obviously I could do a GETMAIN or STORAGE OBTAIN LOC=24 on the way in and :>:>FREEMAIN or STORAGE RELEASE on the way out. But that's less than optimal :>for :>:>a routine that is called multiple times. (And it would not work at all if :>:>the routine had to save state across calls, but fortunately that is not :>the :>:>case, at least for my requirements so far.) :>... :>You can anchor in name/token. -- Binyamin Dissen <bdis...@dissensoftware.com> http://www.dissensoftware.com Director, Dissen Software, Bar & Grill - Israel Should you use the mailblocks package and expect a response from me, you should preauthorize the dissensoftware.com domain. I very rarely bother responding to challenge/response systems, especially those from irresponsible companies. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
