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Date: Wed, 18 Sep 2013 15:19:12 +0200
From: Fabian Keil <freebsd-listen@fabiankeil.de>
To: Mark Johnston <markj@freebsd.org>
Subject: Re: pr_psargs on FreeBSD
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Mark Johnston <markj@freebsd.org> wrote:

> It's kind of a strong-armed approach, but the problem's been around for a
> while and I can't think of any clever solutions - I'd love to see an
> alternative solution.
>=20
> My patch against FreeBSD (pasted below) adds a function called memstr()
> to DTrace. memstr() takes three arguments: addr, c, and len, and returns
> a copy of addr of length len with all null-terminators replaced by c,
> and with the last byte replaced by a null-terminator. In particular,
> memstr() always returns a string of length len - 1, unless len =3D=3D 0, =
in
> which case we return the empty string.
[...]
> and execsnoop works properly. Any thoughts on this function? Have I missed
> a better solution? A patch for FreeBSD is below.

Looks good (and clever) to me and seems to work as expected. Thanks a lot.

I briefly looked into this a couple of months ago and was under
the impression that it would require a lot more code ...

Fabian

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