our @sequence = ( "path1",
                  "path2",
                  # ...
                );

sub nextpath {
    for ( my $i=0; $i<=$#sequence; $i++ ) {
        ( $PATH_INFO eq $sequence[$i] ) or next;
        ( $i < $#sequence )
            ? return( $sequence[$i+1]);
            : return( $sequence[0]);
    }
    undef();
}