sub findCompressor {
    my @paths=(
         "/usr/bin".
         "/bin",
         "/usr/local/bin",
         "/usr/share/bin",
         "/opt/bin",
         "$ENV{HOME}/bin",
         "$ENV{HOME}/local/bin",
    );

    foreach my $prog('bzip2','gzip','compress') {
        foreach my $dir(@paths) {
            my $path="$dir/$prog";
            return $path if -x $path;
        }
    }

    # return some default non-compressing compressor??
}

# run once
my $compressor=findCompress();