/*
 * ISA 563, Spring 2011
 * Copyleft by Muhammad Abdulla
 */

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

/*
 * sigcatch.c -- demonstrates signal handling in programs.
 */

static void sig_handler(int signo)
{
    if ( signo == SIGINT ) {
        printf( "received SIGINT\n");
    } else if ( signo == SIGTSTP ) {
        printf( "received SIGTSTP\n");
    } else if ( signo == SIGHUP ) {
        printf( "received SIGHUP\n");
    } else if ( signo == SIGQUIT ) {
        printf( "received SIGQUIT\n");
    } else if ( signo == SIGTERM ) {
        printf( "received SIGTERM\n");
    } else if ( signo == SIGABRT ) {
        printf( "received SIGABRT\n");
    } else if ( signo == SIGUSR1 ) {
        printf( "received SIGUSR1\n");
    } else if ( signo == SIGKILL) { // cannot catch this
        printf( "received SIGKILL\n");
    } else if ( signo == SIGSTOP) { // cannot catch this
        printf( "received SIGSTOP\n");
    } else { 
        fprintf( stderr, "received signal %d\n", signo);
    }
}

int main(void)
{
    signal(SIGINT, sig_handler);
    signal(SIGTSTP, sig_handler);
    signal(SIGHUP, sig_handler);
    signal(SIGQUIT, sig_handler);
    signal(SIGTERM, sig_handler);
    signal(SIGABRT, sig_handler);
    signal(SIGUSR1, sig_handler);

    // can't catch these two
    signal(SIGKILL, sig_handler);
    signal(SIGSTOP, sig_handler);

    while ( 1 ) {
       pause(); 
    }
}