The most basic form of the sender’s address is the simple "user@domain.com" format. However, you can get fancier with this if you wish, or you can simply leave it in its simple form.

$?x$x <$g>$|$g$.

The default format of the $q macro contains a test conditional (?x). This tests to see if the mail system was able to locate the sender’s full name. If so, write the "From:" header as being from "$x <$g>", or "Full Name <address@domain.com>".

If the system is unable to detect the sender’s full name, then ($|) write the return address as just "$g", or the e-mail address alone.