Well, if you use memory accessible from any address space for the file handling, then writes would be defered until the buffer is full, and the buffer writes would take place after you already return. Reads would have to wait if the requested data is not in the input buffers.
On Sun, May 19, 2019 at 4:19 PM scott Ford <idfli...@gmail.com> wrote: > > I totally agree, that was also my “take” on doing I/O from a system exit. I > realize > there would be performance issues also, but I was asked the question by my > management. Since I am the responsible party, I do the research,design, etc. > I won’t write risky of iffy code, to me that’s not real responsible. > > Scott > > On Sun, May 19, 2019 at 7:59 AM Peter Relson <rel...@us.ibm.com> wrote: > > > Whether or not you are in an environment that would allow you to issue > > I/O, you should also consider whether it is appropriate to do so. > > Doing I/O from a system exit can cause system performance problems. It is > > the responsibility of system exits to be "well behaved".' > > > > It is wrong to assume that lack of documentation means "it is OK". Quite > > the reverse. Lack of documentation means that you should not assume "it is > > OK" -- but you could/should ask that the documentation be clarified to be > > explicit. > > > > Peter Relson > > z/OS Core Technology Design > > > > > > ---------------------------------------------------------------------- > > For IBM-MAIN subscribe / signoff / archive access instructions, > > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > > -- > Scott Ford > IDMWORKS > z/OS Development > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
