#include "unify.h"
int Await(int event_id, int count);
Await(3) blocks the calling process until the event counter
referenced by event_id reaches a value of at least
count. count may be exceeded by the time the
process calling Await(3) unblocks.
Await(3) returns the new value of the event counter upon
success. Otherwise, a value of -1 is returned.