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From: des@des.no (Dag-Erling =?iso-8859-1?Q?Sm=F8rgrav?=)
To: Mike Meyer <mwm-keyword-freebsdhackers2.e313df@mired.org>
References: <017601c6c486$6477c370$0a0aa8c0@rivendell>
	<17640.52899.432083.511555@bhuda.mired.org>
Date: Mon, 21 Aug 2006 12:43:44 +0200
In-Reply-To: <17640.52899.432083.511555@bhuda.mired.org> (Mike Meyer's message
	of "Sun, 20 Aug 2006 17:05:39 -0400")
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Cc: Reko Turja <reko.turja@liukuma.net>, freebsd-hackers@freebsd.org
Subject: Re: Aqcuiring full path to running process from outside the kernel
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Mike Meyer <mwm-keyword-freebsdhackers2.e313df@mired.org> writes:
> However, you can also make a best effort. Check argv[0] to see if you
> have an absolute path. If not, do what the shell would do to find the
> executable - look for it on $PATH. Once you've found it, call
> realpath(3) to canonicalize the path.

You got it the wrong way around.  First pass argv[0] to realpath(3),
fall back to using $PATH only if realpath(3) fails (which it shouldn't
unless you've called chdir(2), chroot(2) or jail(2) earlier in the
process, or the executable was moved or removed)

DES
--=20
Dag-Erling Sm=F8rgrav - des@des.no