bug#9366: Display geometry change hook

[David De La Harpe Golden]

Severity: wishlist

Raised by Edward O'Connor in emacs-devel thread [1], filing in 
bugtracker so it doesn't get lost over the feature freeze period.

Emacs doesn't appear to currently provide a hook that is reliably called 
when the _display_ geometry changes on graphical window systems. e.g. 
screen resolution changed by user, monitor hotplugging.

Emacs frame/window geometry might sometimes be considered to remain the 
same by the window system terms despite changing overall display 
geometry, so e.g. window-configuration-change-hook is not always run 
when the display geometry changes.

Attached is an initial x11-only stab at an implementation that calls 
window-configuration-change-hook when display geometry changes, though a 
separate hook would be another design option.

For ns, Edward also mentioned:

"On GNUStep and Mac OS X, applications can listen for 
NSApplicationDidChangeScreenParametersNotification for this sort of thing"

Dunno about w32 as yet, but presumably it has something similar.


[1] http://lists.gnu.org/archive/html/emacs-devel/2011-08/msg00544.html
From: "Edward O'Connor" <...>
Date: Fri, 12 Aug 2011 10:51:25 -0700
Message-ID: 
<CAME3nGLnjLXixmSY45BWFX6qtCp2_XBR4x6a281hO6Mu=rnSuQ@mail.gmail.com>
Subject: is there a hook run when display geometry changes?

xrandr_monitoring_r1.diff
Description: Text Data