Reading from output

I know it's probably something stupid, but, can I read a line from the stdout? I'm working under GNU/Linux.

Nope, that's asking the stream to go in the wrong direction. In some cases you can read from an output device, such as a terminal screen, by grabbing data from its buffer, but that's not really doable just with stdout.

> but, can I read a line from the stdout?
You mean like a pipe, connecting the stdout of another program to the stdin of your program?

You mean something like this?

Code:

itsme@itsme:~/C$ cat intercept.c
#include <stdio.h>
#include <string.h>

int main(void)
{
  char buf[BUFSIZ], *p;
  int addnl;

  while(fgets(buf, sizeof(buf), stdin))
  {
    if((p = strchr(buf, '\n')))
    {
      *p = '\0';
      addnl = 1;
    }
    else
      addnl = 0;

    printf("Intercepted and passing on: %s\n", buf);

    if(addnl)
      puts(buf);
    else
      fputs(buf, stdout);
  }

  return 0;
}

Code:

itsme@itsme:~/C$ echo "foo bar baz"
foo bar baz
itsme@itsme:~/C$ echo "foo bar baz" | ./intercept
Intercepted and passing on: foo bar baz
foo bar baz
itsme@itsme:~/C$ cat foo.txt
this is some text
this is more text
itsme@itsme:~/C$ cat foo.txt | ./intercept
Intercepted and passing on: this is some text
this is some text
Intercepted and passing on: this is more text
this is more text
itsme@itsme:~/C$

No, it's not a pipe, anyway, I knew that it wasn't logic, but I wasn't totally sure. Thanks you anyway.