Singals and pthreads min. example

#include<pthread.h>
#include<stdio.h>
#include<signal.h>
#include<unistd.h>

void sig_handler(int signo)
{
    printf("received SIGUSR1\n");
    _exit(0);
}

void *theOtherThread(void*) {
    while(true) {} // ∞ cycle
}

int main() {
    if (signal(SIGUSR1, sig_handler) == SIG_ERR)
        printf("\ncan't catch SIGUSR1\n");
    pthread_t thr;
    if (pthread_create(&thr, 0, theOtherThread, 0)) { // invoke a child thread
        perror("Creating thread");
        return 1;
    }
    sleep(1); // sleep one second
    pthread_kill(thr, SIGUSR1); // send signal to the child thread
    if (pthread_join(thr, 0)) { // wait for the child thread to exit
        perror("Creating thread");
        return 1;
    }
    return 0;
}