PHP program to print the version of CGI used by the webserver

Program/Source Code:

The source code to print the version of CGI used by the webserver is given below. The given program is compiled and executed successfully.

<?php
//PHP program to print the version of CGI 
//used by web server.

$version = $_SERVER['GATEWAY_INTERFACE'];

printf("CGI Version: %s<br>", $version);
?>

Output:

CGI Version: CGI/1.1

Explanation:

In the above program, we used $_SERVER['GATEWAY_INTERFACE'] super global that returns the version of  Common Gateway Interface (CGI) used by the web server, which is assigned to the variable $version. After that, we printed the CGI version using printf() on the webpage.