#define _GNU_SOURCE
#include <sched.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>

int main(void)
{
	int pid;

	unshare(CLONE_NEWPID);
	fork();
	pid = fork();
	if (pid == 0) {
		return 0;
	}
	waitpid(pid, NULL, 0);
	return 0;
}