[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Proposal: window-system-version function

From: Dmitry Antipov
Subject: Re: Proposal: window-system-version function
Date: Tue, 22 May 2012 09:51:18 +0400
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120428 Thunderbird/12.0.1

On 05/21/2012 08:20 PM, Eli Zaretskii wrote:

Thanks.  However, this change breaks backward compatibility.  Perhaps
it would be better to leave the variable alone, and _add_ the
function; that would be backward-compatible.

I fixed Lisp code in lisp/international/mule-diag.el and
lisp/textmodes/artist.el; not sure about external packages which
may also use it.

Leaving the variable "as is" means that window-system-version
and (window-system-version) may have different values, which
is confusing. Ideally, window-system-version should be a frame-local
variable, but I'm wondering whether this is possible in Emacs.

+It's value is a number:
+ - 0 for a termcap frame,
+ - Major X protocol version for the frame on X display,
+ - Major OS version for the frame on MS-Windows display,
+ - 24 for the frame on direct-write MS-DOS display,
+ - 10 for the frame on a GNUstep or Macintosh Cocoa display.

This is inaccurate at least for MS-DOS and MS-Windows.  Do we really
want to document the precise meaning of the values here?  Why is that

I'm not sure about exact values on a systems beyond *nix, and I suppose
that every Lisp-visible function should be documented.

+    case output_x_window:
+      return make_number (ProtocolVersion (FRAME_X_DISPLAY (f)));
+    case output_w32:
+      return make_number (w32_major_version);
+#ifdef MSDOS
+    case output_msdos_raw:
+      return make_number (24);

The MSDOS build supports HAVE_X_WINDOWS as well, so HAVE_X_WINDOWS and
MSDOS are not by themselves mutually exclusive.

The cpp stuff above has no mutually exclusive paths (no #elif or so),
so it should work if both HAVE_X_WINDOWS and MSDOS are defined.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]