#include <pthread.h>      
#include <stdio.h>

void *fi();
void *fo();
pthread_t thrdid[2];

char fifo[100000][256];
int fifo_position = 0;

char val[256];
int fi_mark = 0;
int fo_mark = 0;

void put_fifo(char *val)
{
    while (fo_mark != 0);
    fi_mark = 1;
    sprintf(fifo[fifo_position], "%s", val);
    fifo_position++;
    fi_mark = 0;
}

char *get_fifo()
{
    
    while (fi_mark != 0);
    fo_mark = 1;
    sprintf(val, "%s", fifo[fifo_position]);
    if (fifo_position>0)
        fifo_position--;
    fo_mark = 0;
    return (char *)fifo[fifo_position];
}

int main()
{

     pthread_create( &thrdid[0], NULL, fi, NULL);
     pthread_create( &thrdid[1], NULL, fo, NULL);

     for(;;);

    return 0;
}

void *fi()
{
    for (;;)
    {
        put_fifo("test");
    }
}

void *fo()
{
    for (;;)
    {
        printf("%s\n", get_fifo());
    }
}