请问各位高手，pthread_join函数是否必要？

banbi1985

我已经知道，为了防止僵尸进程，父进程会使用wait，或是交给init进程处理。   那么对于线程来说，有没有类似的事情？pthread_join函数是否必要？谢谢

hbmhalley

pthread_detach

hanzhenlll

恩 分离线程比较好。。。

embeddedlwp

回复 3# hanzhenlll


    如果程序中没有调用pthread_join或pthread_detach函数，会造成资源泄漏吗？
   
    还是当main thread 退出时，一切都被回收了？

hbmhalley

回复 4# embeddedlwp

The new thread terminates in one of the following ways:
* It calls pthread_exit(3), specifying an exit status value that is available to another thread in the same process that calls pthread_join(3).
* It returns from start_routine(). This is equivalent to calling pthread_exit(3) with the value supplied in the return statement.
* It is canceled (see pthread_cancel(3)).
* Any of the threads in the process calls exit(3), or the main thread performs a return from main(). This causes the termination of all threads in the process.

man pthread_create(3)

embeddedlwp

回复 5# hbmhalley


    嘿嘿，我是想问如果pthread_create时没有设置detachstate，没有调用pthread_join函数，没有调用pthread_detach函数
    会不会像进程那样变成僵尸，也就是说会不会即使main thread退出了，依旧存在僵死线程？
    求指点！

txdgtwpv

不会僵，和主线程一起死了

banbi1985

txdgtwpv 发表于 2011-12-27 17:48
不会僵，和主线程一起死了

是这个结论吗？

hbmhalley

回复 8# banbi1985


    main return前是僵着的.和进程一样

Failure to join with a thread that is joinable (i.e., one that is not detached), produces a "zombie thread". Avoid doing this, since each zombie thread consumes some system resources, and when enough zombie threads have accumulated, it will no longer be possible to create new threads (or processes).

    main return后就没了

txdgtwpv

banbi1985 发表于 2011-12-27 17:55
是这个结论吗？

没有detach就是这样的