#
# Copyright (c) 1993 Terrence R. Lambert.
# All rights reserved.
#
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# modification, are permitted provided that the following conditions
# are met:
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# This product includes software developed by Terrence R. Lambert.
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#
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# $NetBSD: README,v 1.2 1997/10/13 11:20:10 lukem Exp $
#
1.0 Overview
This is the README file for the sample miscellaneous module
that mimics the loaded system call.
A miscellaneous module may be used to load any data or
program into the kernel that can be made available by
modifying a table, pointer, or other kernel data to inform
the kernel that the module should be used instead of the
previous code/data path.
Generally, it is assumed that a loadable module is one of
a set of similar modules (such as a file system or console
terminal emulation), and that the reference is through a
table (such as vfssw[]), and that a "special" value is
assigned to the slots which are allowed to be replaced.
This is not enforced, so you may use the "miscellaneous"
module any way you see fit.
As with the loadable system calls, it may be desirable to
allow the module loader to replace an *existing* entry to
try out changes to kernel code without rebuilding and
booting from the new kernel.
2.0 Directions
To test the module, do the following:
cd module
make load
A load message (the copyright) will be printed on the console.
cd ../test
make load
The system call prints a message on the console when called.
This message will be printed when running "make load" in
the "test" subdirectory.
3.0 Recovering resources
The miscellaneous module consumes 8 pages of memory when
loaded; it can be freed up by unloading it. To unload it,
type the following from the directory this file is in:
cd module
make unload
The miscellaneous module will be unloaded by name.
4.0 END OF DOCUMENT
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