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  sema-
       phore unchanged).

EXAMPLES

       if (SDL_SemWait(my_sem) == -1) {
               return WAIT_FAILED;
       }

       ...

       SDL_SemPost(my_sem);

SEE ALSO

       SDL_CreateSemaphore, SDL_DestroySemaphore, SDL_SemTryWait, SDL_SemWait-
       Timeout, SDL_SemPost, SDL_SemValue



SDL                         Tue 11 Sep 2001, 23:00              SDL_SemWait(3)