The absolute path is the directory location on a server's hard drive where Joomla! is located.
In Joomla! v.1.0.x the configuration.php file would contain something like the following, however, it can vary depending on your server.
$mosConfig_absolute_path = '/home/joomla/public_html';
To find out what your absolute path is, copy the following code into a text editor (i.e. Notepad, TextEdit etc), save the file as a .php naming it whatever you want (i.e anyfilename.php.).
Using your FTP software, ftp the file you have just created to your root folder. Open a web browser and type in http://www.yourdomain.com/filename.php.
<?php $path = getcwd(); echo "Your Absoluthe Path is: "; echo $path; ?>
IMPORTANT: For security reasons, delete this file as soon as you have ascertained the information you require.
In Joomla! v.1.5.x the absolute path is set in the index.php (line 17) file in the base directory to the constant JPATH_BASE.
define('JPATH_BASE', dirname(__FILE__) );
Use the constant JPATH_BASE. This constant returns the absolute path to your Joomla! installation directory.
<?php echo JPATH_BASE; ?>