iOS多线程编程

iOS多线程编程之NSThread的使用

http://blog.csdn.net/totogo2010/article/details/8010231

线程专题总结

http://www.cocoachina.com/bbs/read.php?tid=43852

NSOperation和NSOperationQueue

http://blog.csdn.net/mengtnt/article/details/6950043

iOS系统GCD学习(5):信号量机制

http://blog.csdn.net/asunchaofan/article/details/8457905