This is the general list of environment variables. These are a series of hidden values that the web server sends to every script you run. These are generally avaiable to CGI, GSL, PL, XML and most other scripts.
| Variable Name | Value | 
|---|---|
| DOCUMENT_ROOT | The root directory of your server | 
| HTTP_COOKIE | The visitor's cookie, if one is set | 
| HTTP_HOST | The hostname of your server | 
| HTTP_REFERER | The URL of the page that called your script | 
| HTTP_USER_AGENT | The browser type of the visitor | 
| HTTPS | "on" if the script is being called through a secure server | 
| PATH | The system path your server is running under | 
| QUERY_STRING | The query string | 
| REMOTE_ADDR | The IP address of the visitor | 
| REMOTE_HOST | The hostname of the visitor (if your server has reverse-name-lookups on; otherwise this is the IP address again) | 
| REMOTE_PORT | The port the visitor is connected to on the web server | 
| REMOTE_USER | The visitor's username (for .htaccess-protected pages) | 
| REQUEST_METHOD | GET or POST | 
| REQUEST_URI | The interpreted pathname of the requested document or CGI (relative to the document root) | 
| SCRIPT_FILENAME | The full pathname of the current CGI | 
| SCRIPT_NAME | The interpreted pathname of the current CGI (relative to the document root) | 
| SERVER_ADMIN | The email address for your server's webmaster | 
| SERVER_NAME | Your server's fully qualified domain name (e.g. www.cgi101.com) | 
| SERVER_PORT | The port number your server is listening on | 
| SERVER_SOFTWARE | The server software you're using (such as Apache 1.3) |