PHP numeric separator, setlocale

Question

I've recently come upon a very intriguing issue. I have the following code on a website to generate a number composed by 10 digits, followed by a period (.), followed by 2 to 4 digits. I also use the gettext function to translate the page into 2 other different languages

<?php
      $lang = "en_UK";
      putenv("LC_ALL=$lang");
      setlocale(LC_ALL, $lang);
      bindtextdomain("messages", "locale");
      bind_textdomain_codeset('messages', 'UTF-8');
      textdomain("messages");

      list($usec, $sec) = explode(" ",microtime());
      $my_number = ((float)$usec + (float)$sec + (float)rand(1, 100000000));
?>
      <form method ="POST" action="">
          <input type="hidden" value="<?php echo $my_number; ?>"/>
          <input type="submit"/>
      </form>

So far so good. When $lang is equal to en_UK, I get what I need (1234567891.1234).

But if $lang is equal to it_IT, or de_DE, then $my_number changes format to 10 digits, followed by a COMMA, followed by 2 to 4 digits (1234567891,1234).

Does anybody now why this happens??? Thanks a lot :)

Answer 1

Different countries have different conventions about how to write numerals. setlocale changes the conventions your program uses.