NetEase/libpomelo — pull request #25 by eminom (2013-06-05 12:35:32+00:00)
Title: One problem in pc_client_destroy

I use pc__client_force_join to force main thread to wait for working thread's end,
and whenever pc_client_destroy is called,

the current lib always try to uv_thread_join client->worker.
Under some linux platform, pthread_join will rise segment fault if join in NULL.