/*-------------------------------------------------------------------*/
/* testalarmtimeout.c                                                */
/* The alarm system call to implement a timeout.                     */
/*-------------------------------------------------------------------*/

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

void mySignalHandler(int iSignal)
{
   printf("\nSorry.  You took too long.\n");
   exit(1);
}

int main(int argc, char *argv[])
{
   int i;

   signal(SIGALRM, mySignalHandler);

   printf("Enter a number:  ");
   alarm(5);
   scanf("%d", &i);
   alarm(0);

   printf("You entered the number %d.\n", i);
   return 0;
}

/* Sample execution:

--> gcc -Wall -ansi -pedantic -o testalarmtimeout testalarmtimeout.c
--> testalarmtimeout
Enter a number:  123
You entered the number 123.
--> testalarmtimeout
Enter a number:  
Sorry.  You took too long.

*/