From: Gary Wright <gwtmp01@...>
Date: 2007-11-07T07:46:29+09:00
Subject: Re: Changing date backward messes up threaded sleep


On Nov 6, 2007, at 4:39 PM, Robert Williams wrote:
> Anyway, my work around was to have a c program send a IPC message  
> to the
> scheduler every second.  At which point the scheduler would watch for
> unusual time deviations and handle things accordingly...i.e. clean  
> up a
> sleeping thread.

Yikes!  You have a scheduling system that spans an entire calendar
year that needs 1-second granularity?  The fact that you even mention
a 'calendar' indicates to me that you want events to be synched to
wall-clock time anyway--so it sounds like a contradiction to want
to ignore wall-clock changes.  Most likely though, I'm not aware
of the entire context you are working in.

FYI, in reading the Ruby code during this thread I think I noticed
that if there is only a single thread that sleep(x) actually uses
select() directly to wait for the elapsed time.  I guess my point
is that if you really want a process to send you an IPC message
every second you can do that with Ruby also--just don't start any
other threads.

Gary Wright