If an error condition occurs, this routine returns an integer indicating the type of error. Possible return values are as follows: Return Description 0 Successful completion. [EINVAL] The value specified by cond, mutex, or abstime is invalid, or Different mutexes are supplied for concurrent tis_cond_timedwait() operations or tis_cond_wait() operations on the same condition variable, or The mutex was not owned by the calling thread at the time of the call. [ETIMEDOUT] The time specified by abstime expired. [ENOMEM] The Threads Library cannot acquire memory needed to block using a statically initialized condition variable.