Wait on the condition variable \fBcond\fR for, at most, \fBms\fR milliseconds\&. \fBmut\fR is unlocked so it must be locked when the function is called\&. Returns \fBSDL_MUTEX_TIMEDOUT\fP if the condition is not signalled in the allotted time, \fB0\fR if it was signalled or \fB-1\fR on an error\&.