\fBSDL_SemPost\fP unlocks the semaphore pointed to by \fBsem\fR and atomically increments the semaphores value\&. Threads that were blocking on the semaphore may be scheduled after this call succeeds\&.
.PP
\fBSDL_SemPost\fP should be called after a semaphore is locked by a successful call to \fISDL_SemWait\fR, \fISDL_SemTryWait\fR or \fISDL_SemWaitTimeout\fR\&.
.SH"RETURN VALUE"
.PP
Returns \fB0\fR if successful or \fB-1\fR if there was an error (leaving the semaphore unchanged)\&.