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Date: Mon, 29 Jun 2015 19:57:41 -0400
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Subject: Re: sysctl(3) man page examples
From: Patrick Kelsey <pkelsey@freebsd.org>
To: Hans Petter Selasky <hps@selasky.org>
Cc: Sean Bruno <sbruno@freebsd.org>, 
 "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>
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On Mon, Jun 29, 2015 at 2:37 PM, Hans Petter Selasky <hps@selasky.org>
wrote:

> On 06/28/15 08:26, Patrick Kelsey wrote:
>
>> s a sysctl entry for it (containing an empty
>> string)
>>
>
> Hi,
>
> FYI:
>
> Until r267960 zero-length strings were not listed by sysctl, which might
> be part of the reason this bug has not been seen before.
>
>
That zero-length string is just a dummy entry to keep the mib name in the
sysctl tree - the true value for that key is supplied by sysctl(3)
directly, so that key should never validly resolve to a zero-length
string.  I believe this bug did not show up because there are vanishingly
few consumers of the user.cs_path sysctl value.

-Patrick