get-orig-source to be called from any directory?

["Eric Lavarde - Debian" <deb@zorglub.s.bawue.de>]

Hello,

I'm trying to add a 'get-orig-source' target to my debian/rules file, and
it looks like this:

get-orig-source:
        debian/export-freemind-cvs.sh 0.8.0+01 FM-0-8-0

It works quite fine, but the Debian policy manual specifies under [1] that
"This target may be invoked in any directory", and my target can obviously
only be invoked from the parent directory of 'debian', the given script is
64 lines long, so I wouldn't like to put it in extenso in the rules file.

Is there something like a $(dirname $0) construct in 'make', or can I
interpret the policy in the sense that the target may be invoked in any
directory, as long as it contains the debian directory? ;-)

Thanks, Eric

[1]
file:///usr/share/doc/debian-policy/policy.html/ch-source.html#s-debianrules
-- 
Eric de France, d'Allemagne et de Navarre