linux-kernel - 3.5.rc2 tty buffering bug ?

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Message-ID: <20120614161331.GA29687@redhat.com>
Date:	Thu, 14 Jun 2012 12:13:31 -0400
From:	Dave Jones <davej@...hat.com>
To:	Linux Kernel <linux-kernel@...r.kernel.org>
Cc:	Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: 3.5.rc2 tty buffering bug ?

I found something odd that happens with redirection.

this code...

#include <stdio.h>

void main()
{
	printf("begin\n");

	if (fork() != 0)
		printf("child\n");
	else
		printf("parent\n");

	printf("end\n");
}

usually exits before the child gets to print anything, so stdout looks like..

begin
parent
end

but when redirected to a file, sometimes it prints what we expect, but other times
(if the child exits first) it seems to print..

begin
child
end
begin
parent
end

How does 'begin' get printed a second time ?

	Dave

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