c++ - Output for simple program using pthread -

void cleanuphandler(void *arg) {      printf("in cleanup handler\n"); } void *thread(void *string) {      int i;     int o_state;     int o_type;     pthread_cleanup_push(cleanuphandler, null);     pthread_setcancelstate(pthread_cancel_disable, &o_state);     pthread_setcanceltype(pthread_cancel_asynchronous, &o_type);     puts("1 hello world");     pthread_setcancelstate(o_state, &o_state);     puts("2 hello world");     pthread_cleanup_pop(0);     pthread_exit(null); } int main() {      pthread_t th;     int rc;     rc = pthread_create(&th, null, thread, null);     pthread_cancel(th);     pthread_exit(null); } 

i wondering output of code , in order happen. yes, practice test question exam have in 6 hours. appreciated. there no office hours today of ta's college busy own finals.

thanks

here man pages need understand problem putting on exam (which won't exact problem above.) need understand each of functions does.

• http://man7.org/linux/man-pages/man3/pthread_cleanup_push.3.html
• http://man7.org/linux/man-pages/man3/pthread_setcanceltype.3.html,
• http://man7.org/linux/man-pages/man3/pthread_cancel.3.html

• http://man7.org/linux/man-pages/man3/pthread_exit.3.html

• cleanup_push pushs handler on stack of functions called if calling thread cancelled or exits.

• setcancelstate temporarily locks out cancels (so can call setcanceltype atomically without weirdness happening.)
• setcanceltype allows/disallows asynchronous cancellation notification.
• cancel attempts cancel other thread.

• exit exits calling thread.

• you need understand whether pthread_setcancelstate cancellation point. find information either on above man pages or on http://man7.org/linux/man-pages/man7/pthreads.7.html.

in question (and presumably similar 1 on exam), need enumerate possible interleavings of calls these functions between 2 threads.