-static bool channel_rec;
-static bool channel_reply;
-static pthread_mutex_t reply_lock = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t reply_cond = PTHREAD_COND_INITIALIZER;
-static pthread_mutex_t recv_lock = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t recv_cond = PTHREAD_COND_INITIALIZER;