From owner-freebsd-hackers  Thu Jan 15 19:45:10 1998
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Date: Thu, 15 Jan 1998 22:52:33 -0500 (EST)
From: Alex Boisvert <alex@gel.usherb.ca>
Reply-To: boia01@gel.usherb.ca
To: freebsd-hackers@FreeBSD.ORG
Subject: procfs: intercept calls?
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I've just read in a USENIX abstract that it's possible "to intercept
specific system calls" with the /proc filesystem, and service the call
with a user-level program.

Is this feasible on FreeBSD?  I've just read the procfs man page a few
times and can't see any mention about this.  I suppose that one doesn't
manually overwrite the process' text segment where the syscalls are
made...

Maybe it's source-code documented? ;-) 

Alex.