SDL_!SemWait

SDL_!SemWait

NAME SYNOPSIS DESCRIPTION RETURN VALUE EXAMPLES SEE ALSO

NAME

SDL_!SemWait- Lock a semaphore and suspend the thread if the semaphore value is zero.

SYNOPSIS

#include

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_!SemValue