After the init file has done loading I get this message in the minibuffer:
For information about GNU Emacs and the GNU system, type C-h C-a.
What is it being triggered by and how do I change it?
display-startup-echo-area-message triggers this little advertisement unless you're using customize and have set it there or have it set in your
user-init-file (because it actually goes ahead and scans this file for something looking like that, see the definition of
display-startup-echo-area-message for the gory details).
There is a way to replace it with something completely different though, simply by redefining it in your Emacs configuration:
(defun display-startup-echo-area-message () (message "Let the hacking begin!"))
This is being triggered by
display-startup-echo-area-message, which gets called at startup time.
This particular message is made intentionally difficult to remove (I guess because the GNU project feels they need the advertisement).
You can still disable it by customizing
M-x customize-variable inhibit-startup-echo-area-message RET
The Help Text for
Non-nil inhibits the initial startup echo area message. Setting this variable takes effect only if you do it with the customization buffer or if your init file contains a line of this form:
(setq inhibit-startup-echo-area-message "YOUR-USER-NAME")
If your init file is byte-compiled, use the following form instead:
(eval '(setq inhibit-startup-echo-area-message "YOUR-USER-NAME"))
If you use an Emacs config shared between machines (eg. through version control) and can't enter your username explicitly, you can use:
(put 'inhibit-startup-echo-area-message 'saved-value t) (setq inhibit-startup-echo-area-message (user-login-name))
...as per advice from the bug mailing list. This sets the
saved-value property on the variable
inhibit-startup-echo-area-message before setting it to your login name, which circumvents the intended safety feature (of leaving a user with no instructions for getting help if they copy and paste init code).