http://perldoc.perl.org/perluniintro.html

##</code><code>##

    sub nice_string {
        join("",
            map { $_ > 255 ? 
                sprintf("\\x{%04X}", $_) :  
                chr($_) =~ /[[:cntrl:]]/ ? 
                sprintf("\\x%02X", $_) :    
                quotemeta(chr($_))         
            } unpack("W*", $_[0])
         )           
     }