clone TGID, PID

clone_pt.c

#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <linux/unistd.h>
#define _GNU_SOURCE
#include <linux/sched.h>

void sub_func(void *arg)
{
	printf("TGID(%d), PID(%d) : Child \n", getpid(), syscall(__NR_gettid));
	sleep(2);
	return 0;
}

int main(void)
{
    int pid;
    int child_a_stack[4096], child_b_stack[4096];
	
	printf("before clone \n \n");
	printf("TGID(%d), PID(%d) : Parent \n", getpid(), syscall(__NR_gettid));
	
	clone(sub_func, (void *)(child_a_stack+4095), CLONE_CHILD_CLEARTID | CLONE_CHILD_SETTID, NULL);
	clone(sub_func, (void *)(child_b_stack+4095), CLONE_VM | CLONE_THREAD | CLONE_SIGHAND, NULL);
	
	sleep(1);
	
	printf("after clone \n \n");
    return 0;
}