为php Web应用程序获取自动递增的内部版本号的最佳方法是什么？

$var = \'$Id:$\';

$Rev:$

cd /var/www/project
svn update
rm version.php
svnversion > version.php

$path=\'path_to_your_project\';
function get_svn_revision ($path)
{
    $cmd = \'svnversion -n \' . $path;
    $result = (int)exec ($cmd);
    return $result;
}

$path=\'path_to_your_project\';
function get_svn_revision($path) {
    $svn = File($path . \'/.svn/entries\');
    //Revision number is the fourth line
    $result = $svn[3];
    unset($svn);
    return $result;
}