// Source: http://alumni.cs.ucr.edu/~drougas/code-samples-tutorials/signals.c

#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <unistd.h>

// SIGALARM = 14
// SIGCHLD =  17

void signalHandler(int signal) {
     printf("Cought signal %d!\n",signal);
     if (signal==SIGCHLD) {
	 printf("Child ended\n");
 	 wait(NULL); }}

int main() {
	signal(SIGALRM,signalHandler);
	signal(SIGUSR1,signalHandler);
	signal(SIGCHLD,signalHandler);
	if (!fork()) {
   	    printf("Child running...\n");
	    sleep(2);
	    printf("Child sending SIGALRM...\n");
	    kill(getppid(),SIGALRM); 
	    sleep(5);
	    printf("Child exitting...\n");
	    return 0; }
	printf("Parent running, PID=%d. Press ENTER to exit.\n",getpid());
	getchar();
	printf("Parent exitting...\n");
	return 0; }