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/* hashfork.c
*
* by Hubert Chan
*
* This file is hereby placed in the public domain.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <time.h>
#include <signal.h>
#include <sys/wait.h>
const int NUM_PROCS=15;
int main (int argc, char *argv[])
{
int i;
pid_t children[NUM_PROCS];
pid_t pid;
int status;
for (i = 0; i < NUM_PROCS; i++)
{
pid = fork ();
if (pid)
{ /* parent */
children[i] = pid;
}
else
{
int wait_time = 0;
pid = getpid ();
printf ("process %d started.\n", pid);
/* this should be a function call to calculate the hashcash instead of
* an execl */
execl ("/usr/bin/hashcash", "/usr/bin/hashcash", "-mb25", "foo", NULL);
exit(0);
/* --- ignore this --- */
srand (time (NULL) + pid);
wait_time = rand () % 20;
printf ("%d: waiting %d seconds.\n", pid, wait_time);
sleep (wait_time);
printf ("%d: exiting.\n", pid);
exit (0);
}
}
pid = wait (&status);
printf("process %d exited.\nkilling all children.\n", pid);
for (i = 0; i < NUM_PROCS; i++)
{
printf ("%d\n", children[i]);
kill (children[i], SIGKILL);
}
return 0;
}
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