(PHP 5 >= 5.3.0)
timezone_version_get — Gets the version of the timezonedb
Returns the current version of the timezonedb.
Returns a string.
Example #1 Getting the timezonedb version
<?php
echo timezone_version_get();
?>
以上例程的输出类似于：
2009.7
Omar (2011-09-14 22:15:36)
On Ubutu:
If you get 0.system for the version, this means you have the version that PHP shipped with. For a newer version, you must upgrade via the PECL extension (sudo pecl install timezonedb)
http://pecl.php.net/package/timezonedb
Ubuntu (2011-06-16 10:35:41)
On Ubuntu 11.04 it returns the string "0.system".