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From: Matthew Jakeman <m.jakeman@lancaster.ac.uk>
Organization: Lancaster University
To: hackers@freebsd.org
Date: Wed, 15 Oct 2008 13:43:28 +0100
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Subject: Call function on sysctl value change
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Hi all,

I was wondering if it is possible to call a function when a sysctl value is 
changed. I have added a few sysctl int variables to the kernel and for some 
of these i only want certain values to be acceptable as input depending on 
some conditions. I would like to be able to call a function if possible, to 
validate the value entered via the sysctl command.

Thanks in advance
Matt