On 12/10/2011 6:22 AM, Steve Comstock wrote:
Hmmm. Are you advocating use of semiprivileged instructions in application code then? Or only some of them? Which ones are 'safe' or 'OK' to use in standard application programs? Where does one draw the line?
Once your minimum supported operating system enables use of a particular semi-privileged instruction, then you can use it just the same as you would any new macro-based system service provided by that same level of the OS. If you write code for multiple operating systems, you need to take extra care. For example, very old z/VSE systems (pre-VSE/ESA 2.5?) used to not enable 'extraction-authority control' so often-used instructions like IPK would not work in problem state. Thankfully, that is ancient history now. I haven't seen a similar mismatch between z/OS and z/VSE in quite a while. Nevertheless, if your code might run under multiple operating systems, this is a consideration. -- Edward E Jaffe Phoenix Software International, Inc 831 Parkview Drive North El Segundo, CA 90245 310-338-0400 x318 [email protected] http://www.phoenixsoftware.com/
