[PD] key and keyup question

Simon Wise simonzwise at gmail.com
Mon Jul 13 05:26:15 CEST 2009

 > that behaviour comes from the OS, those objects listen to the events
 > that are sent to pd from the X server, not to the raw USB events that
 > [hidio] uses. To fix your problem you have change the key repeat
 > preferences on whatever OS you are using. You may also find you have
 > issues with which window is in focus - to receive the events the
 > appropriate pd window must be in focus.

It took me a little while to work this out, so I'll share this in case 
anyone is looking at similar problems, and wants to control exactly what 
inputs are used by X and when, so they can use keyboards, mice, tablets 
etc as controls in pd without also controlling the pointer etc ...

A month or two ago Debian Sid moved to the new version of Xorg [some of 
the other distributions moved over earlier] and this has meant huge 
changes to the way input devices are dealt with, and now HAL is the 
primary way that X gets info about accessing devices. It is now possible 
to have a nearly empty xorg.conf, or even no xorg.conf at all. It is 
also possible to stick with the old style of configuration if you wish, 
but you will have to add a couple of extra lines to your old xorg.conf 
if this is what you want.

This article is well worth reading to find out more:


It seems that the HAL way of doing things, using it's configuration 
files, is a lot more flexible and much more hot-pluggable than the old 
way, but uses a completely different set of configuration files.

I have been wondering how hard it would be to make [hidio] into 
something that works through HAL, maybe called [halio], to be able to 
access many devices that register with HAL instead of just USB devices, 
but to stick with a very similar interface to [hidio], and preferably 
stay compatible for usb-hid devices?? It would of course be Linux only 
because HAL is a purely Linux way of doing things.

That would be a very long-term learning exercise for me, with no results 
for some time, if at all - but the results would be great!

Some other commands you may want to look at for more tricks, all 
extremely easy to set up in Debian, then usable in pd with a few scripts 
and [shell] (or maybe use pdreceive in a pipe?) are the ones that create 
X events - so that you can create mouse and keyboard events, moving the 
windows of other apps around and sending keystrokes, mouse events, text 
selections and more - try out these packages ...

xdotool xautomation xsel

plus these utilities from x11-utils to help: xev xwininfo xprop


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