Treat initial-scratch-message as a doc string

* doc/emacs/building.texi (Lisp Interaction):
* doc/lispref/os.texi (Startup Summary):
* etc/NEWS: Document this.
* lisp/startup.el (initial-scratch-message):
Look up find-file’s key rather than hardcoding it.
(command-line-1): Substitute the doc string.
This also substitutes the quotes, which will help test display
quoting at startup.

1 files changed, 3 insertions, 3 deletions

diff --git a/lisp/startup.el b/lisp/startup.el
index c152e0122ae..e0249593893 100644
--- a/lisp/startup.el
+++ b/lisp/startup.el
@@ -1390,11 +1390,11 @@ settings will be marked as \"CHANGED outside of Customize\"."
 
 (defcustom initial-scratch-message (purecopy "\
 ;; This buffer is for notes you don't want to save, and for Lisp evaluation.
-;; If you want to create a file, visit that file with C-x C-f,
+;; If you want to create a file, visit that file with \\[find-file],
 ;; then enter the text in that file's own buffer.
 
 ")
-  "Initial message displayed in *scratch* buffer at startup.
+  "Initial documentation displayed in *scratch* buffer at startup.
 If this is nil, no message will be displayed."
   :type '(choice (text :tag "Message")
                  (const :tag "none" nil))
@@ -2430,7 +2430,7 @@ nil default-directory" name)
          (get-buffer "*scratch*")
          (with-current-buffer "*scratch*"
            (when (zerop (buffer-size))
-             (insert initial-scratch-message)
+             (insert (substitute-command-keys initial-scratch-message))
              (set-buffer-modified-p nil))))
 
     ;; Prepend `initial-buffer-choice' to `displayable-buffers'.