Last Updated: 18 Oct 2017 GMT +8.
This is a patch to add an informational header to messages sent from PHP via the mail() function. This can help to track which script on a server was used to send a message, and which client caused it to be sent.
The header added has the form:
X-PHP-Script: <servername><php-self> for <remote-addr>
X-PHP-Script: www.example.com/~user/testapp/send-mail.php for 10.0.0.1
If the connection appears to have come via a proxy cache (i.e. has an "X-Forwarded-For" header), is a list of addresses (the addresses in X-Forwarded-For, then the 'real' remote address).
Read more at Steve Bennett's patch as I created my patches according to his patch with a little tweak/modification since his patch only available for version 4.3.4 during the time I checked and also won't be working for mail function example 1 as listed at php manual. Steve Bennett's original patch can be found here.