If an error condition occurs, this routine returns an integer value indicating the type of error. Possible return values are as follows: Return Description 0 Successful completion. [EAGAIN] The system lacks the necessary resources to initialize another condition variable, or The system-imposed limit on the total number of condition variables under execution by a single user is exceeded. [EBUSY] The implementation has detected an attempt to reinitialize the object referenced by cond, a previously initialized, but not yet destroyed condition variable. [EINVAL] The value specified by attr is not a valid attributes object. [ENOMEM] Insufficient memory exists to initialize the condition variable.