#include<stdio.h>
#include<pthread.h>
void* say_hello(void* data)
{
	char
	*str;
	str = (char*)data;
	while(1){
		printf("%s\n",str);
		sleep(1);
	}
}

void main() {
	pthread_t t1,t2;
	pthread_create(&t1,NULL,say_hello,"hello from 1");
	pthread_create(&t2,NULL,say_hello,"hello from 2");
	pthread_join(t1,NULL);
}