#ios->多线程

多线程GCD_semaphore

@property (nonatomic, strong) void (^dispath_queueNoParaCompletion)(void);
@property (nonatomic, strong) void (^dispath_queueCompletion)(dispatch_semaphore_t semaphore);

+(void)callSemaphoreSyncQueueUseConcurrentStr:(char*)constChar  WithCompletionBlock:(void(^)(dispatch_semaphore_t semaphore))completionBlock
{
    if (completionBlock) {
        self.dispath_queueCompletion = completionBlock;
    }
    dispatch_queue_t  queue = dispatch_queue_create(constChar, DISPATCH_QUEUE_CONCURRENT);
    dispatch_async(queue, ^{
        dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);
        !self.dispath_queueCompletion ? :self.dispath_queueCompletion(semaphore);
    });
  
}

 [JJDispatch_queue callSemaphoreSyncQueueUseConcurrentStr:"example" WithCompletionBlock:^(dispatch_semaphore_t  _Nonnull semaphore) {
        [self actionA:^{
            dispatch_semaphore_signal(semaphore);
            NSLog(@"A-------->>>>>");
        }];
        
        dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
        [self actionB:^{
            sleep(3);
            dispatch_semaphore_signal(semaphore);
            NSLog(@"B-------->>>>>");
        }];

        dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
        [self actionC:^{
            NSLog(@"C-------->>>>>");
        }];
    }];
    
    
    
    -(void)actionA:(void(^)(void))completionBlock
{
    if (completionBlock) {
         _NoParaCompletion=completionBlock;
        _NoParaCompletion();
    }
    
}

-(void)actionB:(void(^)(void))completionBlock
{
    if (completionBlock) {
        _NoParaCompletion =completionBlock;
        _NoParaCompletion();
    }
}

-(void)actionC:(void(^)(void))completionBlock
{
    if (completionBlock) {
        _NoParaCompletion =completionBlock;
        _NoParaCompletion();
    }
    
}