handling Signal

linux signal hander

#include <signal.h>
#include <unistd.h> // for STDOUT_FILENO
#include <stdio.h>
void handler(int num) {
    write(STDOUT_FILENO, "refuse to die\n", 13);
}
int main() {
    // with sigaction, second ctrl + C will work
    /*
    struct sigaction sa;
    sa.sa_handler = handler;
    sigaction(SIGINT, &sa, nullptr);
    */
    signal(SIGINT, handler); // ctrl + C will not work forever
    while(1) {
        printf("infinite loop with pid:%d\n", getpid());
        sleep(1);
    }
    return 0;
}