Condition Mutexes

[dsimcha]

== Quote from Bartosz Milewski (bartosz-nospam at relisoft.com)'s article
> dsimcha Wrote:
> > void main() {
> >     condition = new Condition( new Mutex() );
> >     auto T = new Thread(&waitThenPrint);
> >     T.start();
> >     condition.notify();  // Never wakes up and prints FOO.
> > }
> Your program terminates immediately after sending the notification. You need to
stall the exit until the other thread has a chance to wake up.

Thanks.  I've implemented this, along w/ one other suggestion from another poster.
 Here's the new program.  It still doesn't work.  Has anyone successfully used
core.sync.condition from druntime *on D2, not the Tango version on D1*?  If it
works, then it should be better documented so people who aren't already threading
gurus can figure out how to use it.  If it doesn't work, then as soon as I can
confirm that I'm not the problem, I'll go file a bug report.

Bartosz, since you're a threading guru, could you please write a simple test
program using core.sync.condition and see if it works, and if not either file a
bug report or let me know?

import core.sync.mutex, core.sync.condition, core.thread, std.stdio;

__gshared Condition condition;
__gshared Mutex mutex;

void waitThenPrint() {
    mutex.lock;
    condition.wait();
    mutex.unlock;
    writeln("FOO");
}

void main() {
    mutex = new Mutex;
    condition = new Condition(mutex);
    auto T = new Thread(&waitThenPrint);
    T.start();
    condition.notify();  // Never wakes up and prints FOO.
    T.join;
}