pthread TGID, PID (gcc -o pthread_pt pthread_pt.c -lpthread)

pthread_pt.c

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

void *t_function(void *data)
{
	int id;
	int i=0;
	pthread_t t_id;
	id = *((int *)data);
	printf("TGID(%d), PID(%d), pthread_self(%d) : Child \n", getpid(), syscall(__NR_gettid), pthread_self());
	sleep(2);
}

int main(void)
{
    int pid, status;
    int a = 1;
	int b = 2;
	pthread_t p_thread[2];
	printf("before pthread_create \n \n");
	if((pid = pthread_create(&p_thread[0], NULL, t_function, (void*)&a)) < 0) {
		perror("thread create error : ");
		exit(1);
	}
	if((pid = pthread_create(&p_thread[1], NULL, t_function, (void*)&b)) < 0) {
		perror("thread create error : ");
		exit(2);
	}
	pthread_join(p_thread[0], (void **)&status);
	printf("pthread_join(%d) \n", status);
	pthread_join(p_thread[1], (void **)&status);
	printf("pthread_join(%d) \n", status);
	printf("TGID(%d), PID(%d) : Parent \n", getpid(), syscall(__NR_gettid));
    return 0;
}