Usando pipes

[demonofnight]

Dae, estou tentando usar pipes com um sort como exemplo, quero fazer uma enrada de dados e pegar a saida, porem o codigo não funciona, estou meio perdido na teoria, alguém poderia me ajudar?

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <iostream>
#define WRITE 1
#define READ 0

using namespace std;

int main()
{
        char    buf[5];
        int     fd_in[2], fd_out[2],
                c;
        pipe(fd_in);pipe(fd_out);
        if(fork() == 0)
        {
                close(fd_in[WRITE]);dup2(fd_in[READ], READ);
        close(fd_out[READ]); dup2(fd_out[WRITE], WRITE);

        dup2(fd_out[WRITE], WRITE); //stdout -> pipe's write (everything what would go to stdout will go to the pipe's write...
                execlp("sort", "sort", NULL);
        }

        write(fd_out[1], "c\n", 2);
        write(fd_out[1], "a\n", 2);
        write(fd_out[1], "b\n", 2);

        while((c = read(fd_in[0], buf, 5)) > 0)
                write(1, buf, c);

        return  0;
}

Vlw pelo help galera

Edited January 6, 2012 by kuroi
Adicionar tag CODE