ah sorry, don't need that `or' in server.el:
          (unless (or files commands)
            (switch-to-buffer
             (get-buffer-create
              (cond
               ((stringp initial-buffer-choice) (find-file-noselect
initial-buffer-choice))
               ((functionp initial-buffer-choice) (funcall
initial-buffer-choice))
               (t "*scratch*")))
             'norecord))



2012/12/22 Constantin Kulikov <zxnotdead@gmail.com>

> // Discussion in devel.
> https://lists.gnu.org/archive/html/emacs-devel/2012-12/msg00521.html
> Short:
> I want to be able to set buffer that will be displayed in window of newly
> created frame.
> I need it for my emacs package, that will save and restore some emacs
> state including
> last window configurations, opened and displayed buffers and such.
> I tried this: add hook to `after-make-frame-functions'. Inside this hook I
> do
> `(switch-to-buffer <some-buffer>)' and frame is switched to that
> <some-buffer> at first,
> but after a short time it's switched to *scratch*.
>
> The one way I found how to overcome this behaviour is by setting the
> `initial-buffer-choice' in the `after-make-frame-functions' hook. One
> drawback of this
> approach is that it could only be set to name of file, t or nil and so
> there is no way to
> force switching to buffer without underlying file. This could be fixed int
> server.el:1258
> replacing
>
>   (unless (or files commands)
>         (if (stringp initial-buffer-choice)
>         (find-file initial-buffer-choice)
>           (switch-to-buffer (get-buffer-create "*scratch*")
>                 'norecord)))
>
> to
>           (unless (or files commands)
>             (switch-to-buffer
>              (get-buffer-create
>               (or (cond
>                    ((stringp initial-buffer-choice) (find-file-noselect
> initial-buffer-choice))
>                    ((functionp initial-buffer-choice) (funcall
> initial-buffer-choice)))
>                   "*scratch*"))
>              'norecord))
>
> and modified defcustom in in startup.el:41 would be:
>
> (defcustom initial-buffer-choice nil
>   "Buffer to show after starting Emacs.
> If the value is nil and `inhibit-startup-screen' is nil, show the
> startup screen.  If the value is a string, visit the specified file
> or directory using `find-file'.  If t, open the `*scratch*'
> buffer. If function, switch to a buffer returned by this function.
>
> A string value also causes emacsclient to open the specified file
> or directory when no target file is specified."
>   :type '(choice
>       (const     :tag "Startup screen" nil)
>       (directory :tag "Directory" :value "~/")
>       (file      :tag "File" :value "~/.emacs")
>       (function  :tag "Function")
>       (const     :tag "Lisp scratch buffer" t))
>   :version "23.1"
>   :group 'initialization)
>
> This code allows setting `initial-buffer-choice' to a function returning
> needed buffer.
>
>