if    (substr($text, 0, 4) eq "\x00\x00\xFE\xFF") { utf32be }
elsif (substr($text, 0, 4) eq "\xFF\xFE\x00\x00") { utf32le }
elsif (substr($text, 0, 2) eq "\xFE\xFF"        ) { utf16be }
elsif (substr($text, 0, 2) eq "\xFF\xFE"        ) { utf16le }
elsif (substr($text, 0, 3) eq "\xEF\xBB\xBF"    ) { utf8    }
else {
   No BOM found. Might not be UTF.
   Use another method to guess the
   encoding.
}