pthread_detach question

Question

Till recently, I was under the impression that if you "detach" a thread after spawning it, the thread lives even after the "main" thread terminates.

But a little experiment (listed below) goes contrary to my belief. I expected the detached thread to keep printing "Speaking from the detached thread" even after main terminated, but this does not seem to be happening. The application apparently terminates...

Do the "detached" threads die after "main" issues return 0?

#include <pthread.h> #include <stdio.h>  void *func(void *data) {     while (1)     {         printf("Speaking from the detached thread...\n");         sleep(5);     }     pthread_exit(NULL); }  int main() {     pthread_t handle;     if (!pthread_create(&handle, NULL, func, NULL))     {         printf("Thread create successfully !!!\n");         if ( ! pthread_detach(handle) )             printf("Thread detached successfully !!!\n");     }      sleep(5);     printf("Main thread dying...\n");     return 0; } 

Answer 1

To quote the Linux Programmer's Manual:

The detached attribute merely determines the behavior of the system when the thread terminates; it does not prevent the thread from being terminated if the process terminates using exit(3) (or equivalently, if the main thread returns).

Also from the Linux Programmer's Manual:

To allow other threads to continue execution, the main thread should terminate by calling pthread_exit() rather than exit(3).