threading / timers / etc

[Ryan Lortie <desrt desrt ca>]

Hello

We have an agreement at the hackfest that I will do the following things
now:

  - Starting immediately, glib will depend on librt (and therefore
    libpthread) on systems that have it.

  - We will add GTimeSpec which is GTimeVal using nanoseconds instead of
    microseconds (same story with struct timeval vs. struct timespec).
    The librt interfaces provide this level of accuracy so it would be a
    shame to needlessly discard it.

  - We will expose an API in glib that gives the monotonic time (if
    possible) or otherwise falls back to the wall clock time.  gthread
    on Windows is using GetSystemTimeAsFileTime for example (which is
    wall clock time), so not much more we can do there...

  - g_source_get_current_time() will be deprecated and replaced with an
    API based on monotonic time.

  - Existing sources in glib (timeouts, mostly) will use monotonic time
    instead of wall clock time.

  - GPeriodic will use monotonic time for the timestamp value to the
    "tick" parameter.

  - The rules about initialising the thread system do not change at all.

We also plan the following for the future ("glib 4.0"):

  - libgthread will stop existing, be folded into libglib and it will
    become impossible to replace the default threading implementation
    for your platform.  Threads will be "turned on" always.

Comments?

Cheers