在编译陈硕github上面的代码时，遇到了链接错误：
../Thread.o: In function `(anonymous namespace)::ThreadNameInitializer::ThreadNameInitializer()': Thread.cpp:(.text+0x5f): undefined reference to `pthread_atfork' ../Thread.o: In function `muduo::Thread::~Thread()': Thread.cpp:(.text+0x3f9): undefined reference to `pthread_detach' ../Thread.o: In function `muduo::Thread::start()': Thread.cpp:(.text+0x50e): undefined reference to `pthread_create' ../Thread.o: In function `muduo::Thread::join()': Thread.cpp:(.text+0x5ce): undefined reference to `pthread_join' collect2: error: ld returned 1 exit status
在编译时已经加了-lpthread，还是有这个问题。
在这里找到了答案：http://stackoverflow.com/questions/2373109/what-library-to-be-to-be-used-to-avoid-undefined-reference-to-pthread-atfork
pthread_atfork是POSIX标准，在编译时要加上-pthread
-lpthread是老版本的gcc编译器用的，在新版本中应该用-pthread取代-lpthread
参考链接
解决undefined reference to `pthread_atfork`/`pthread_detach`/`pthread_create`/`pthread_join`