bug#1165: 23.0.60; doc of make-frame-command

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Date: Tue, 14 Oct 2008 10:42:43 -0700
> Cc: 
> 
> (if (and window-system (not (eq window-system 'pc)))
>     (make-frame)
>   (select-frame (make-frame)))
>  
> 1. Why the difference for `pc'?

`pc' is the value of window-system for the MS-DOS build of Emacs.  The
MS-DOS build behaves like a text terminal, but its window-system has a
non-nil value; thus the difference.

Although correct, that code should actually be rewritten using
display-graphic-p to become cleaner.

> 2. What does the doc string mean by "terminal" and "if the terminal
> displays only one frame"?

It means the text-only terminals, which can only display one frame at
a time.

> If "terminal" refers only to emacs -nw, then nothing is said about
> the window-manager case.

Well, I think it does say something about the windowed terminals: it
says that on those terminals, a new frame is created, but it is not
selected.