Concurent Ping-Pong Example C<P-THREADS>

pthread1.c

#include <pthread.h>
#include<stdlib.h>

//64 BITS -ALL 32 bit Arch
//32 BIT - UNIX 64 bit arch
//64 BIT - WINDOWS 64 bit arch
long long sum = 0;
static enum turn
{
  PING,
  PONG
}def;
void* sum_runner(void* arg)
{
    long long* limit_ptr = (long long *) arg;
    long long limit = *limit_ptr;//Derefrencing
    for(long long i=0; i<=limit; i++)
        sum += i;
    printf("Sum is %lld \n", sum);
    pthread_exit(0);
}

void ping()
{
  puts("Ping");
  def = PONG;
}

void pong()
{
  puts("Pong");
  def = PING;
}


int main(int argc, char **argv)
{
    if(argc<2)
    {
	puts("Usage ./objFile <num>"); 
        exit(1);
    }
	
    long long limit = atoll(argv[1]);
    def = PING;


    pthread_t t_id;
    pthread_attr_t attr;

    pthread_attr_init(&attr);

    pthread_create(&t_id,&attr,sum_runner,&limit);
    //Main Functions
    for(int i=0; i<= 10; i++)
    {
	if(def == PING)
           ping();
        else if(def == PONG)
           pong();
        else
           puts("UNKOWN PI-PO");           
    }   
	
    pthread_join(t_id,NULL);
}