* added the php tag to activate the syntax highlight

get_ethernet_addresses.php

<?php
/**
 * Get the all interface mac addresses.
 * 
 * @return array|integer Return the MAC adresses as an array OR if the exec() call failed the return will be the error code from "ipconfig /all". 
 */
function get_ethernet_addresses()
{
	$physicalAddresses = array();
	$ipconfig_output = array();
	$return = 0;
	
	exec('ipconfig /all', $ipconfig_output, $return); 
	
	if( $return == 0 )
	{
		// https://regex101.com/r/uN9dF4/3
		foreach( $ipconfig_output as &$line)
		{
			// Empty previous values
			$matches = array();
			// Let's find the MAC adresses
			if( preg_match("/([[:blank:]][[:xdigit:]]{2}-[[:xdigit:]]{2}-[[:xdigit:]]{2}-[[:xdigit:]]{2}-[[:xdigit:]]{2}-[[:xdigit:]]{2})$/i", $line, $matches) )
			{
				$physicalAddresses[] = trim($matches[0]);
			}
		}
		return $physicalAddresses;
	}
	return $return;
}