condition_wait
Description:
Waits for condition to become true on this.
When the condition is met, true is returned.
If cancellable is cancelled before the condition is met, or if the socket has a timeout set and it is reached before the condition
       is met, then false is returned and throws, if non-
      null, is set to the appropriate value (g_io_error_cancelled or 
      g_io_error_timed_out).
See also condition_timed_wait.
Parameters:
| this | a Socket | 
| condition | a IOCondition mask to wait for | 
| cancellable | a Cancellable, or null | 
Returns:
| true if the condition was met, false otherwise |