How can I use multiple input devices on a single computer?

Question

I'm looking for software available on any major operating system (Windows, OSX, any Linux derivative) that supports the use of any/all of the below:

• Multiple mice (to control different cursors)
• Multiple keyboards (so 2 separate text editors can be used simultaneously)

_{(source: dicolab.com)}

I've considered the below workarounds:

• Using VNC software to connect to the computer (less than idea because >1 computer is necessary)
• TeamPlayer (unviable because base version costs more than 500USD)
• Online collaboration software including Google Docs / Office 365 (preference for use on same computer with large screen)

Ideally, I'd like a solution that's priced reasonably (less than 50 USD), though I'm flexible depending on how good a match it is.

Answer 1

On newer Linuxes (since around 2.4.x), there are different character devices in /dev/input for every user input source:

/dev/input/by-id:
total 0
drwxr-xr-x 2 root root 120 Jul 18 09:55 .
drwxr-xr-x 4 root root 280 Jul 18 09:55 ..
lrwxrwxrwx 1 root root   9 Jul 18 09:55 usb-VMware_VMware_Virtual_USB_Mouse-event-mouse -> ../event3
lrwxrwxrwx 1 root root   9 Jul 18 09:55 usb-VMware_VMware_Virtual_USB_Mouse-if01-event-mouse -> ../event4
lrwxrwxrwx 1 root root   9 Jul 18 09:55 usb-VMware_VMware_Virtual_USB_Mouse-if01-mouse -> ../mouse2
lrwxrwxrwx 1 root root   6 Jul 18 09:55 usb-VMware_VMware_Virtual_USB_Mouse-mouse -> ../js0

/dev/input/by-path:
total 0
drwxr-xr-x 2 root root 180 Jul 18 09:55 .
drwxr-xr-x 4 root root 280 Jul 18 09:55 ..
lrwxrwxrwx 1 root root   9 Jul 18 09:55 pci-0000:02:02.0-usb-0:1:1.0-event-mouse -> ../event3
lrwxrwxrwx 1 root root   6 Jul 18 09:55 pci-0000:02:02.0-usb-0:1:1.0-mouse -> ../js0
lrwxrwxrwx 1 root root   9 Jul 18 09:55 pci-0000:02:02.0-usb-0:1:1.1-event-mouse -> ../event4
lrwxrwxrwx 1 root root   9 Jul 18 09:55 pci-0000:02:02.0-usb-0:1:1.1-mouse -> ../mouse2
lrwxrwxrwx 1 root root   9 Jul 18 09:55 platform-i8042-serio-0-event-kbd -> ../event1
lrwxrwxrwx 1 root root   9 Jul 18 09:55 platform-i8042-serio-1-event-mouse -> ../event2
lrwxrwxrwx 1 root root   9 Jul 18 09:55 platform-i8042-serio-1-mouse -> ../mouse0

In case of the X, you can easily set up in Xorg.conf, which device do you want to use for your different X instances:

Section "InputDevice"
  Identifier  "Mouse0"
  Driver      "mouse"
  Option      "Protocol" "auto"
  Option      "Device" "/dev/input/mice"
  Option      "ZAxisMapping" "4 5 6 7"
EndSection

Unfortunately, it requires manual editing of the X config files, but it works perfectly. Maybe there is some software/tool to automatize this task.

And a last thing. You will have to construct two different xorg.conf files for the task. So, you will have to run two different X servers, running independently.

But it is not a problem, because your X instances are normally started/stopped by a display manager. And they can do that. For example, in the case of the ubuntu-default lightdm, you will have to edit them into /etc/lightdm.

Answer 2

Linux can support this under X Win as in this article by using MPX with many of the items I found talking specifically about ArchLinux but many applications do not support it well.

Answer 3

If your main goal is collaboration then maybe you should look into the concurrency editing options which Google docs offers. This is an alternative approach to what you are asking for, but it is a tested solution. A few times me and some friends have used our smartphones editing a common document displayed on a TV using chromecast from the single computer. It works really well with spreadsheets, but can be a little confusing to watch.

The advantage of this, and possible similar conferencing tools, is that the computer displaying the stuff doesn't need to handle multiple input sources which would require multiple focus points which most OS'es doesn't handle very well. After all this is what conferencing tools are all about, whilst a computer is mostly intended for a single user.