From mboxrd@z Thu Jan  1 00:00:00 1970
From: j.neuschaefer@gmx.net (Jonathan =?utf-8?Q?Neusch=C3=A4fer?=)
Date: Tue, 29 Jul 2014 20:49:16 +0200
Subject: How to implement a driver's read and write operations with
	synchronization properly
In-Reply-To: <40703.1406643881@turing-police.cc.vt.edu>
References: <CAPmaJ=A65RqKw6nzVufMPsWOFJehcD-d0r+yom1Pa3F2eHCgGA@mail.gmail.com>
	<40703.1406643881@turing-police.cc.vt.edu>
Message-ID: <20140729184915.GK3694@debian>
To: kernelnewbies@lists.kernelnewbies.org
List-Id: kernelnewbies.lists.kernelnewbies.org

On Tue, Jul 29, 2014 at 10:24:41AM -0400, Valdis.Kletnieks at vt.edu wrote:
> On Tue, 29 Jul 2014 20:59:08 +0700, Anh Le said:
> 
> > still, user programs like bash could have a race problem by spliting
> > the input, I hope that they can somehow take care of this problem
> > themselves.
> 
> stdio is *not* always your friend.  fopen/fprintf is prone to splitting on
> bugger boundaries without your knowing about it, but most language bindings
> (including the Perl you tested with) allow you to use open/write and do the
> buffer management yourself
> 

Actually, the Perl's IO layer did pretty little to the result, because
Anh used command line substitution:

	echo $(perl -e "print 'a'x2000") > /dev/sample


Jonathan