On Wed, 01 Mar 2017, Marcus MERIGHI <mcmer-open...@tor.at> wrote: > sc...@ggr.com (Scott Bonds), 2017.02.28 (Tue) 02:21 (CET): >> I'm polling using xrandr to check whether a new display was plugged >> in, so I can run a script to switch to it, i.e. plug in an external >> VGA monitor and it lights up automatically, unplug it and my laptop >> automatically switches back to using its internal display. > > I have wanted the same and found no way to avoid polling xrandr(1). > > If you find a way, would you be so kind to share the solution?
The Other Operating System has something called udev rules. I have a file called /etc/acpi/hotplug-monitor.sh which queries for connected displays and includes logic to set them up (falling back on xrandr --auto if nothing else makes sense). The file is invoked by udev, per another file named /etc/udev/rules.d/80-hotplug-monitor.rules which has this one line: SUBSYSTEM=="drm", ACTION=="change", RUN+="/etc/acpi/hotplug-monitor.sh" I don't have any OpenBSD box nearby (:C), but perhaps there's something in /var/log/* about a new monitor being plugged in? A process could follow the file and trigger events. <3,K.
