/*-------------------------------------------------------------------*/
/* testforkloop.c                                                    */
/* Context switching among concurrent processes.                     */
/*-------------------------------------------------------------------*/

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

#define TRUE 1

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

   printf("Parent process (%ld)\n", (long)getpid());
   fflush(stdout);

   iPid = fork();

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

   if (iPid == 0)
   {
       for (i = 0; TRUE; ++i)
       {
          printf("Child process (%ld):  %d\n", (long)getpid(), i);
          fflush(stdout);
       }
       _exit(0);  /* Should never reach. */
   }

   for (i = 0; TRUE; ++i)
   {
      printf("Parent process (%ld):  %d\n", (long)getpid(), i);
      fflush(stdout);
   }

   return 0;  /* Should never reach. */
}

/* Sample execution:

$ gcc -o testforkloop testforkloop.c
$ testforkloop
Parent process (1276) 
Parent process (1276):  0 
Parent process (1276):  1 
...
Parent process (1276):  580 
Parent process (1276):  581 
Child process (1277):  0 
Child process (1277):  1 
...
Child process (1277):  62 
Child process (1277):  63 
Parent process (1276):  582 
Parent process (1276):  583 
...

*/