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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] lpdaemon
Date: Wed,  5 Jun 2013 10:09:27 -0400	[thread overview]
Message-ID: <d408485f231154579a59a0bd31e0a99c@kw.quanstro.net> (raw)
In-Reply-To: <F5E95FDE-7218-4C69-BB5E-8EE4FC90D5CC@gmail.com>

> You're absolutely correct if the length of value to be copied is not
> validated prior to the copy.  Then, an invalid page could be hit if no
> nil is present within the array or beyond.

wrong.  strncpy only copies up to the specified maximum.
the code is ugly but correct.

> To be verbose, my bypassing of strncpy is due to issues I've
> encountered in multi-threaded code.  e.g.  Don't trust libc copy
> functions in MT envs, always check post call.

this sounds like your saying that because you had trouble in
a multithreaded unix application, then without examining the
code at hand, it is pronounced to have the same issue.

that sounds like equivocation to me.  the code is correct.
and in all cases nul-terminated, and any unused bytes are
0.

i only object to strncpy because it requires extra work. seprint,
snprint are a bit heavy weight but tend to produce cleaner looking
code.  ymmv.

- erik



  reply	other threads:[~2013-06-05 14:09 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-05 11:38 yaroslav
2013-06-05 13:06 ` erik quanstrom
2013-06-05 13:13 ` Don Bailey
2013-06-05 13:20   ` erik quanstrom
2013-06-05 13:40     ` Don Bailey
2013-06-05 13:38   ` Friedrich Psiorz
2013-06-05 13:54     ` Don Bailey
2013-06-05 14:09       ` erik quanstrom [this message]
2013-06-05 14:29         ` Don Bailey

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