resume a calling thread

[Sean Kelly]

pause and resume are really intended for use by the garbage collector 
and shouldn't really be called in user code, as pausing a thread that's 
executing a system call or holding a lock can cause other threads to 
hang waiting for that resource.  I'm not sure how well it applies to 
Phobos, but Ares has a ThreadGroup class specifically for what you're 
trying to do.  Use is simple:

     void main() {
         void run() {
             printf( "running\n" );
             Thread.sleep( 10000 );
             printf( "done\n" );
         }

         ThreadGroup g = new ThreadGroup;
         g.create( &run );
         g.create( &run );
         g.joinAll( false );
     }

The 'false' paramater to joinAll removes thread references when they 
have completed, allowing the objects to be collected by the GC. 
Currently, this works via foreach and Walter has said that altering a 
data structure during foreach is technically illegal, but I haven't 
found the time to develop a workaround.  In any case, it works just fine 
at the moment.


Sean