#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
int main()
{
    int out, in, err;

    char *cFifo = "/tmp/out";
    char *cInFifo = "/tmp/in";

    mkfifo(cFifo, S_IRUSR|S_IWUSR);
    mkfifo(cInFifo, S_IRUSR|S_IWUSR);

    out = open(cFifo, O_RDWR|O_TRUNC|O_NONBLOCK);
    in = open(cInFifo, O_RDWR|O_TRUNC|O_NONBLOCK);

    dup2(out, STDOUT_FILENO);
    dup2(out, STDERR_FILENO);
    dup2(in, STDIN_FILENO);


    scanf("%*c");

    while(1)
    {
        scanf("%*c");
        printf("Hellon");
        fflush(stdout);
    }

    return 0;
}

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
int main()
{

    int out, in;
    size_t i = 0;

    char bufOut[1024];
    char *cFifo = "/tmp/out";
    char *cFifoIn = "/tmp/in";

    out = open(cFifo, O_RDONLY);

    in = open(cFifoIn, O_WRONLY);


    while(1)
    {
        i =0;
        while(!i)
        {
            i = read(out, bufOut, 1024);
        }

        if(i)
            write(STDOUT_FILENO, bufOut, i);

    }
    return 0;
}