$real_dolibarr_main_document_root=str_replace('\\','/',realpath($dolibarr_main_document_root));// A) Value found into config file, to say where are store htdocs files. Ex: C:/xxx/dolibarr, C:/xxx/dolibarr/htdocs
$pathroot=$_SERVER["DOCUMENT_ROOT"];// B) Value reported by web server setup, to say where is root of web server instance. Ex: C:/xxx/dolibarr, C:/xxx/dolibarr/htdocs
if(!empty($_SERVER["DOCUMENT_ROOT"])){
$pathroot=$_SERVER["DOCUMENT_ROOT"];// B) Value reported by web server setup, to say where is root of web server instance. Ex: C:/xxx/dolibarr, C:/xxx/dolibarr/htdocs
}else{
$pathroot='NOTDEFINED';
}
$paths=explode('/',str_replace('\\','/',$_SERVER["SCRIPT_NAME"]));// C) Value reported by web server, to say full path on filesystem of a file. Ex: /dolibarr/htdocs/admin/system/phpinfo.php
// Try to detect if $_SERVER["DOCUMENT_ROOT"]+start of $_SERVER["SCRIPT_NAME"] is $dolibarr_main_document_root. If yes, relative url to add before dol files is this start part.