I'm using Boost 1.39 on WindowsXP and I noticed that if a process crashes while waiting on an interprocess condition variable, the signaling process blocks forever in subsequent calls to notify_all(). It looks to me like boost is not using the native facilities, but some emulation, so is this scenario not supported by the emulation? The code is very simple: Process A: while (1) { { scoped_lock lock(mut); cond.wait(lock); // Process A might be killed or die while in this call // do some work } } Process B: void notifyOthers() { scoped_lock lock(mut); cond.notify_all(); } I've actually omitted one small detail in the description above. After process A dies, process B can execute notifyOthers() again only once. The second time it never makes it out of the notify_all(). -- Gabriel Burca