reeze/tipi

第八章第二节里面说到的getpid获取的不是pid而是tgid，怎么理解

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zhoumengkang commented

在Linux中叫进程ID，在系统调用fork期间生成，只是我们通过getpid返回的不是其pid字段，而是其线程组号tgid。

不是父进程中返回子进程的pid，在子进程中返回0吗？

这里的getpid作何理解呢？

c9n commented

You might be wondering why does getpid() return tgid, the thread group ID ? In normal processes, the TGID is equal to the PID. With threads, the TGID is the same for all threads in a thread group. This enables the threads to call getpid() and get the same PID.

zhoumengkang commented

@c9n 感谢！