/*-------------------------------------------------------------------*/
/* testkill.c                                                        */
/* The kill system call.                                             */
/*-------------------------------------------------------------------*/

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

/* The kill function should be declared in unistd.h, but is not.  So
   we must declare it explicitly. */
int kill(pid_t iPid, int iSignal);

int main(int argc, char *argv[])
{
   int i = 0;
   int iPid;
   int iRet;
   
   printf("Parent process (%ld)\n", (long)getpid());

   fflush(NULL);
   iPid = fork();
   if (iPid == -1) {perror(argv[0]); return 1; }

   if (iPid == 0)
   {
      /* This code is executed by only the child process. */
      while (1)
      {
         printf("Child process (%ld):  %d\n", (long)getpid(), i);
         i++;
      }
      exit(0);  /* Should never reach. */
   }

   /* Sleep for 1 second. */
   sleep(1);

   iRet = kill(iPid, SIGKILL);
   if (iRet == -1) {perror(argv[0]); return 1; }

   return 0;
}

/* Sample execution:

$ gcc -Wall -ansi -pedantic -o testkill testkill.c 
$ testkill 
Parent process (29497)
Child process (29498):  0
...
Child process (29498):  1918
Child process (29498):  1919
Child process (29498):  1920
Child process (
$

*/