Instruct emacs --batch to wait for something

[Rodrigo Morales]

I'm trying to use Emacs as a tool for getting the text representation of
a website. For doing this, I'm using "eww" and I've written the
following command that I intend to use in the command line.

#+begin_src bash
emacs \
  --batch \
  --eval='(eww 
"https://www.gnu.org/software/emacs/manual/html_node/emacs/Intro.html";)' \
  --eval='(with-current-buffer "*eww*" (princ (buffer-string)))'
#+end_src

The problem with this command is that it shows the following instead of
showing the website.

#+RESULTS:
#+begin_example
Loading https://www.gnu.org/software/emacs/manual/html_node/emacs/Intro.html...
#+end_example

My question is: How can I instruct Emacs to wait for something when the
=--batch= flag is used?