I sometimes write shell scripts which manipulate packages and
would like to get at some of the package internal variables, eg,
$WRKSRC, $PATCHDIR, etc.  Is there already a way to do this?  If not,
could the the following target (or similar) be added to bsd.pkg.mk:

echo:
	@${ECHO} $($(ECHO_VAR))


Then from the pkg directory, one can type

make ECHO_VAR=WRKSRC echo

to get the value of $WRKSRC

This can be used in shell scripts as:

#!/bin/csh -h
set ws=`make ECHO_VAR=WRKSRC echo`
echo Working source directory is $ws