+sub abs2rel ($$) {
+ # Work around very innefficient behavior in File::Spec if abs2rel
+ # is passed two relative paths. It's much faster if paths are
+ # absolute!
+ my $path="/".shift;
+ my $base="/".shift;
+
+ require File::Spec;
+ my $ret=File::Spec->abs2rel($path, $base);
+ $ret=~s/^// if defined $ret;
+ return $ret;
+}
+