[uClibc]Re: stderr problem

[Miles Bader]

On Wed, Aug 28, 2002 at 08:36:58AM -0400, cfowler wrote:
> fd = open(ttyname(), O_WRONLY);
> dup2(fd, 2);
> close(fd);

That's not really a good method, because it (1) redirects stderr to the tty
(if there _is_ a tty!), and (2) doesn't re-establish the stderr stdio stream
(you can use fdopen to do that).

I think it's better to just stash away the stderr file-descriptor with `dup'
before you redirect stderr in the first place.

But you're probably right, it's a good idea to dup2 the `restored' stderr fd
back to fd 2, just so anybody that expects that won't get confused.

So a revised recipe might be:

  (1) Before you do the `freopen', do:

        int saved_fd = dup (2);

  (2) After you've closed f, do:

	dup2 (saved_fd, 2)
	close (saved_fd);
        stderr = fdopen (2, "w");'

-Miles
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