Question

I want to make a command-line app that can be used like this:

$push_to_emacs_buffer "some text"

Then the current running Emacs will append some text into its current active buffer.

Any idea on how to achieve that?

Answer 1

Try

emacsclient -e '(with-current-buffer (window-buffer (selected-window)) (insert "some text"))'

On Linux, push-to-emacs-buffer can be implemented like this:

#!/bin/sh

emacsclient -e "(with-current-buffer (window-buffer (selected-window)) \
                  (insert \"$@\"))"