sub create_dirs {
    use File::Spec;
    my $file = shift;
    my $dir;
    foreach ( File::Spec->splitdir( (File::Spec->splitpath( $file ))[1] ) ) {
        $dir = File::Spec->catdir($dir, $_);
        next if -d $dir;
        mkdir( $dir ) || die $!;
    }
}