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);
DESCRIPTIONSDL_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 suc-
cessful it will atomically decrement the semaphore value.
After SDL_SemWait() is successful, the semaphore can be
released and its count atomically incremented by a suc-
cessful call to SDL_SemPost.
RETURN VALUE
Returns 0 if successful or -1 if there was an error (leav-
ing 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_SemValue
SDL Tue 11 Sep 2001, 23:00 SDL_SemWait(3)