SDL_SemWait
Name
SDL_SemWait -- Lock a semaphore and suspend the thread if the semaphore value is zero.
Synopsis
#include "SDL.h"
#include "SDL_thread.h"
int SDL_SemWait(SDL_sem *sem);
Description
SDL_SemWait() suspends the calling thread until either
the semaphore pointed to by sem has a positive value,
the call is interrupted by a signal or error. If the call is successful it
will atomically decrement the semaphore value.
After SDL_SemWait() is successful, the semaphore
can be released and its count atomically incremented by a successful call to
SDL_SemPost.
Return Value
Returns 0 if successful or
-1 if there was an error (leaving the semaphore unchanged).
Examples
if (SDL_SemWait(my_sem) == -1) {
return WAIT_FAILED;
}
...
SDL_SemPost(my_sem);