On Tuesday, 10/22/2002 at 06:50 CET, Alan Cox <[EMAIL PROTECTED]> wrote: > On Tue, 2002-10-22 at 18:17, Davis, Jeff wrote: > > zVM will not adjust its own time. You can use the DEFINE TIMEZONE and SET > > TIMEZONE commands to change the time for VM. Be sure to adjust your SYSTEM > > CONFIG file accordingly. Guest systems, however, may not take this well. > > How quaint > > To answer the other Linux question. The date can also be altered (root > only) by the date command. Time zone is settable by any user as an > environment variable.
I think you are getting the wrong idea. CMS uses local time for its operations, not UTC. What that means is that it uses the TOD and applies the timezone offset (as supplied by diagnose 0). Other timestamps are obtained from CP (using other diagnose codes) which are defined to return local time, not UTC. SET TIMEZONE does not change the TOD clock - it changes the offset returned by diag 0 and the offset used to compute local time in the other diagnose codes. I don't know of any part of the Linux that uses the VM-provided local time or timezone offset. Now, VM does provide a facility for a guest to learn about timezone shifts. If someone wanted to write the driver for it, Linux could learn when SET TIMEZONE is done, and change the default TZ on the fly. But, presumably Linux can already handle this itself without any assistance from external sources. Alan Altmark Sr. Software Engineer IBM z/VM Development
