I'm trying to use pipes to write some data on a program stdin and get the stdout.
I found this one on the internet and changed it, (the original didn't seems to work to):
Code:
#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;
}
I need to write some data on the sort's stdin and get the stdout, someone can help me?