# Call as path( $workstation, $server )
sub path {
    my ( $workstation, $server, @start ) = @_;

    # initial invocation; make the ws the whole of the path
    if ( !@start ) {
        return path( $workstation, $server, $workstation );
    }

    my $last_hop = $start[ -1 ];

    # found the server; we're done!
    if ( $last_hop eq $server ) {
        return @start;
    }

    # for every possible next hop,
    NEXT_HOP:
    foreach my $next_hop ( get_next_hops( $last_hop ) ) {
        # if it's already in our path somewhere, skip it.
        foreach my $previous_hop ( @start ) {
            next NEXT_HOP if ( $previous_hop eq $next_hop );
        }
        # look for a path with this as the next hop
        my @out = path( $workstation, $server, @start, $next_hop );

        # if a path was found, return it
        return @out if @out;
    }

    # dead end
    return ();
}