/*-------------------------------------------------------------------*/
/* testsignalignore.c                                                */
/* Ignoring signals in the parent (but not the child) process.       */
/*-------------------------------------------------------------------*/

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

#define TRUE 1

int main(int argc, char *argv[])
{
   int iPid;
   int i;
   
   signal(SIGINT, SIG_IGN);
   
   iPid = fork();

   if (iPid == -1)
   {
      printf("Failed to execute fork.\n");
      exit(1);
   }

   if (iPid == 0)
   {
       signal(SIGINT, SIG_DFL);

       for (i = 0; TRUE; ++i)
          printf("Child process:  %d\n", i);
       _exit(0);  /* Should never reach this line. */
   }

   for (i = 0; TRUE; ++i)
      printf("Parent process:  %d\n", i);

   return 0;
}

/* Sample execution:

$ testsignalignore
Parent process:  0
Parent process:  1
...
Child process:  0
Child process:  1
...
^C                      <- Kills child process, but not parent process
Parent process:  12345
Parent process:  12346
...

*/

/* Note:  Must use kill command to stop parent process. */