fifo

#include <iostream>
#include <sys/types.h>
#include <unistd.h>
#include <sys/stat.h>
#include <fcntl.h>
const char * FIFO_NAME_IN = "/home/box/in.fifo";
const char * FIFO_NAME_OUT = "/home/box/out.fifo";
const int MAX_BUF = 80;

int main()
{
    int readfd, writefd, n;
    char buf[MAX_BUF];

    mkfifo(FIFO_NAME_IN, 0666);
    mkfifo(FIFO_NAME_OUT, 0666);

    if ((readfd = open(FIFO_NAME_IN, O_RDONLY)) < 0)
    {
        std::cout<<"Cannot open FIFO_IN\n";
        return 0;
    }
    if ((writefd = open(FIFO_NAME_OUT, O_WRONLY)) < 0)
    {
        std::cout<<"Cannot open FIFO_out\n";
        return 0;
        }

    while ( (n = read(readfd, buf, MAX_BUF)) > 0)
    {
        if (write(writefd, buf, n) != n)
        {
            std::cout<<"Output error\n";
            return 0;
        }


    }
    close(readfd);
    close(writefd);

    return 0;
}