pthreads in C - pthread_exit

Question

For some reason I thought that calling pthread_exit(NULL) at the end of a main function would guarantee that all running threads (at least created in the main funct

Answer 1

pthread_join does the following :

The pthread_join() function suspends execution of the calling thread until the target thread terminates, unless the target thread has already terminated. On return from a successful pthread_join() call with a non-NULL value_ptr argument, the value passed to pthread_exit() by the terminating thread is made available in the location referenced by value_ptr. When a pthread_join() returns successfully, the target thread has been terminated. The results of multiple simultaneous calls to pthread_join() specifying the same target thread are undefined. If the thread calling pthread_join() is canceled, then the target thread will not be detached.

However you can achieve the same by using a light weight loop which will prevent the exe from exiting. In Glib this is achieved by creating a GMainLoop, in Gtk+ you can use the gtk_main. After completion of threads you have to quit the main loop or call gtk_exit.

Alternatively you can create you own wait functionality using a combination of sockets,pipes and select system call but this is not required and can be considered as an exercise for practice.