Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mtxinu!shore
From: shore@mtxinu.COM (Melinda Shore)
Newsgroups: comp.unix.internals
Subject: Re: Interfaces for accessing kernel memory
Message-ID: <1410@mtxinu.COM>
Date: 1 Dec 90 23:33:31 GMT
References: <109449@convex.convex.com>
Reply-To: shore@mtxinu.com (Melinda Shore)
Organization: mt Xinu, Berkeley
Lines: 24

In article <109449@convex.convex.com> tchrist@convex.com (Tom Christiansen) writes:
>I've heard that some vendors have a system (or is it library) call for
>returning you chunks out of the kernel.  Can anyone tell me how they
>seem to work?

Both Unicos and Mach have system calls to return the current contents
of selected kernel data structures.  In both cases you pass in which
structures you want (header files include constants such as TBL_PROCINFO),
starting address and number of elements (for arrays), and a pointer to
where you want the data stuffed.  How do they seem to work?  They seem
to work great.  The only limitation I've run into with either of them
is that they don't necessarily provide access to all of the structures
in which you might be interested.  On the other hand, Mach's table()
call with give you the u. area for any process, and that's such a win
that it overrides any regrets I might have about missing structures like
the file table (which are still available through the standard nlist/
lseek/read mechanism).

There's certainly no reason that it has to be implemented as a system
call.
-- 
                      Deport Neil Bush
Melinda Shore                                 shore@mtxinu.com
mt Xinu                              ..!uunet!mtxinu.com!shore