Bug#33186: electric-fence: Documentation improvement

["J.H.M. Dassen \(Ray\)" <jdassen@wi.leidenuniv.nl>]

Package: electric-fence
Version: 2.0.5-4

README.debian does not explain how to use Electric Fence from within gdb
without having to relink the binary. One can find out how to do this by
perusing the gdb docs thoroughly, but it would be nice if this readme would
include an enlightening example, like these definitions for ~/.gdbinit:

###############################################################################
# Electric Fence
#
# Debian's Electric Fence package provides efence as a shared library, which is
# very useful.
###############################################################################

define efence
	set environment EF_PROTECT_BELOW 0
	set environment LD_PRELOAD /usr/lib/libefence.so.0.0
	echo Enabled Electric Fence\n
end
document efence
Enable memory allocation debugging through Electric Fence (efence(3)).
	See also nofence and underfence.
end


define underfence
	set environment EF_PROTECT_BELOW 1
	set environment LD_PRELOAD /usr/lib/libefence.so.0.0
	echo Enabled Electric Fence for undeflow detection\n
end
document underfence
Enable memory allocation debugging for underflows through Electric Fence 
(efence(3)).
	See also nofence and underfence.
end


define nofence
	unset environment LD_PRELOAD
	echo Disabled Electric Fence\n
end
document nofence
Disable memory allocation debugging through Electric Fence (efence(3)).
end



I'm not sure this is the best way to do it: this assumes LD_PRELOAD isn't
needed otherwise. Perhaps it is possible to rework an existing LD_PRELOAD
value, but I'm not familiar enough with gdb's extension language.

-- System Information
Debian Release: 2.1
Kernel Version: Linux zensunni 2.2.1-ac5 #1 Sat Feb 6 14:20:09 CET 1999 i686 unknown
-- 
Ray Dassen <ray@liacs.nl>