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Subject: Re: libprocstat(3): retrieve process command line args and environment
From: Stanislav Sedov <stas@freebsd.org>
In-Reply-To: <201301221648.50747.jhb@freebsd.org>
Date: Tue, 22 Jan 2013 14:17:39 -0800
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References: <20130119151253.GB88025@gmail.com>
 <201301221201.06290.jhb@freebsd.org> <20130122211743.GA4490@gmail.com>
 <201301221648.50747.jhb@freebsd.org>
To: John Baldwin <jhb@freebsd.org>
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Cc: Mikolaj Golub <trociny@freebsd.org>, freebsd-hackers@freebsd.org,
 Robert Watson <rwatson@freebsd.org>
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On Jan 22, 2013, at 1:48 PM, John Baldwin <jhb@freebsd.org> wrote:
>=20
> Well, you could make procstat open a kvm handle in both cases (open a =
"live"=20
> handle in the procstat_open_sysctl() case).  It just seems rather =
silly to be=20
> duplicating code in the two interfaces.  More a question for Robert: =
does=20
> libprocstat intentionally duplicate the code in libkvm for other =
things as=20
> well in the live case?  (Like fetching the list of processes?)
>=20

It does not actually has a duplicate code, the code for fetching the =
list of
processes via sysctl is different from the KVM case.  The open file =
descriptors
processing is different as well.  Because libprocstat implements almost =
the
same functionality both for sysctl and mvm backends, it can be used to =
analyze
both the live system and the kernel crash dumps.  The code Mikolaj =
proposed
only implements the sysctl backend currently, so it does not seem to =
have
any relation to KVM, so it will be a bit weird to make it open a KVM =
handle
though it does not use it.

--
ST4096-RIPE