PHP Server Vars

ServerVars.php

$_SERVER["DOCUMENT_ROOT"] === /home/user/public_html
$_SERVER["SERVER_ADDR"]   === 143.34.112.23
$_SERVER['HTTP_HOST']     === example.com (or with WWW)
$_SERVER["REQUEST_URI"]   === /folder1/folder2/yourfile.php?var=blabla
__FILE__                  === /home/user/public_html/folder1/folder2/yourfile.php
basename(__FILE__)        === yourfile.php
__DIR__                   === /home/user/public_html/folder1/folder2 [same: dirname(__FILE__)]
$_SERVER["QUERY_STRING"]  === var=blabla

$_SERVER["REQUEST_URI"]   === /folder1/folder2/yourfile.php?var=blabla
parse_url($_SERVER["REQUEST_URI"], PHP_URL_PATH)  === /folder1/folder2/yourfile.php 
$_SERVER["PHP_SELF"]      === /folder1/folder2/yourfile.php

//if "YOURFILE.php" is included in "PARENTFILE.php" , and "PARENTFILE.PHP?abc"   is opened:
$_SERVER["PHP_SELF"]       === /parentfile.php
$_SERVER["REQUEST_URI"]    === /parentfile.php?abc
$_SERVER["SCRIPT_FILENAME"]=== /home/user/public_html/parentfile.php
str_replace($_SERVER["DOCUMENT_ROOT"],'', str_replace('\\','/',__FILE__ ) )  === /folder1/folder2/yourfile.php
//excellent solution to find origin
$debug_files = debug_backtrace();       $initial_called_file = count($debug_files) ? $debug_files[count($debug_files) - 1]['file'] : __FILE__;