SDL_SemWait(3) SDL API Reference SDL_SemWait(3)
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);
SEE ALSO
SDL_CreateSemaphore,
SDL_DestroySemaphore,
SDL_SemTryWait,
SDL_SemWaitTimeout,
SDL_SemPost,
SDL_SemValueSDL Tue 11 Sep 2001, 23:00 SDL_SemWait(3)
