Variable: url-mail-command
url-mail-command is a customizable variable defined in url-vars.el.gz.
Value
compose-mail
Documentation
This function will be called whenever URL needs to send mail.
It should enter a mail-mode-like buffer in the current window.
The commands mail-to and mail-subject should still work in this
buffer, and it should use mail-header-separator if possible.
Source Code
;; Defined in /usr/src/emacs/lisp/url/url-vars.el.gz
(defcustom url-mail-command 'compose-mail
"This function will be called whenever URL needs to send mail.
It should enter a mail-mode-like buffer in the current window.
The commands `mail-to' and `mail-subject' should still work in this
buffer, and it should use `mail-header-separator' if possible."
:type 'function
:group 'url)