If you want to forward your email to an e-mail pipe script like mymailpipe.php, which is located on your public html folder like "/home/username/public_html/mymailpipe.php", In the "Email" Section of your cPanel, click on "Forwarders" and then click on "Add Forwarders".
On the "Add a New Forwarder" page you will see the "Address to forward:" field. If you want to forward your [email protected] to your custom e-mail address, enter "mymail" in the "Address to forward" field, and should you have multiple domains, select the appropriate one from the domain drop-down list.
In the "Destination" field click on "Advanced Options" to expand them, select "Pipe to a Program" and enter the full path of your custom email pipe script such as "home/username/public_html/mymailpipe.php" (Without the quotes, and you may have noticed that we do not use a slash at the beginning of the url.)
Click on the "Add Forwarder" Button.