我在使用時,信號用值大於0IOS信號燈的等待不會等待
sema = dispatch_semaphore_create(2);
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
//signals here
});
dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
dispatch_release(sema);
不應該等待必須等待創建dispatch_semaphore_wait(..)問題兩個信號? 在上面的代碼中,它不會等待,所以釋放被調用,結果是崩潰!