Anthony Williams:
We should probably think of a way to enable the use of a monotonic clock with the absolute timeout overloads. It doesn't feel right to make the relative overloads the only way to access the functionality.
Yes, we should. However, absolute time is always going to have issues with clock changes --- if I schedule for something now (2007-11-27 18:23:15 UTC by the current clock) to run tomorrow (2007-11-28 18:23:15 UTC), does it schedule for 24-hours from now, or for when-the-clock-reads the right time?
These are UTC times. The monotonic clock (CLOCK_MONOTONIC) is not user-settable and for it, now+K always occurs after K seconds. For CLOCK_REALTIME, it schedules for the given time. http://www.opengroup.org/onlinepubs/009695399/functions/pthread_condattr_get... http://www.opengroup.org/onlinepubs/000095399/functions/clock_getres.html