#!env perl

# ***** BEGIN LICENSE BLOCK *****
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is mozilla.org Code.
#
# The Initial Developer of the Original Code is
# Netscape Communications Corporation.
# Portions created by the Initial Developer are Copyright (C) 2002
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
#
# Alternatively, the contents of this file may be used under the terms of
# either of the GNU General Public License Version 2 or later (the "GPL"),
# or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
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# decision by deleting the provisions above and replace them with the notice
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# the provisions above, a recipient may use your version of this file under
# the terms of any one of the MPL, the GPL or the LGPL.
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# ***** END LICENSE BLOCK *****

use File::Spec::Unix;
use strict;

print "Usage: $0 dest_path start_path\n" if ($#ARGV+1 != 2);
my $finish = my_canonpath(shift);
my $start = my_canonpath(shift);

my $res = File::Spec::Unix->abs2rel($finish, $start);

#print STDERR "abs2rel($finish,$start) = $res\n";
print "$res\n";

sub my_canonpath($) {
    my ($file) = @_;
    my (@inlist, @outlist, $dir);

    # Do what File::Spec::Unix->no_upwards should do
    my @inlist = split(/\//, File::Spec::Unix->canonpath($file));
    foreach $dir (@inlist) {
	if ($dir eq '..') {
	    pop @outlist;
	} else {
	    push @outlist, $dir;
	}
    }
    $file = join '/',@outlist;
    return $file;
}