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Date: Sun, 23 Nov 1997 12:10:21 +0200
From: Nadav Eiron <nadav@barcode.co.il>
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To: Rob Miracle <rwm@mpgn.com>
CC: freebsd-questions@FreeBSD.ORG
Subject: Re: Odd error message
References: <199711211814.NAA20364@Central.KeyWest.MPGN.COM>
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Rob Miracle wrote:
> 
> I did a netstat -a and got the following message:
> 
> netstat: kvm_read: Bad address
> 
> The netstat I had done one minute earlier was fine and the one I did 2
> seconds later was fine, but this one was odd.  What does this mean?

netstat traverses some data structures in the kernel without locking
them. This means that it may follow a pointer while the kernel is
updating its structures, causing it to attempt to access non-existent
data. This is what you get as result. One way to lessen the chance of
this happening is running netstat -n, which will execute faster with
less chance of the structures changing on the fly. Other than that, just
hope to be lucky next time...

> 
> Thanks
> Rob
> 
> --
> Rob Miracle <rwm@TanSoft.com>
> Tantalus Inc.
> Be patient or be a patient. -- Anton Devious
Nadav