I used to have an option in settings in Kubuntu 10.10 to do this. Now I cannot find it in 11.04. Where can I find it ? or was it removed ?
Direct link to the window manager-independent solution: http://www.webupd8.org/2009/11/ubuntu-automatically-disable-touchpad.html
I just found the solution for the problem:
- install kde-config-touchpad package.
- Run Utilities->Touchpad Management and the application will have the option in GUI.
Use synclient (for Synaptic devices, i.e. most touchpads), which (as of 14.04) ships by default with Ubuntu:
$ synclient TouchpadOff=1
turns the touchpad off
$ synclient TouchpadOff=0
turns it back on.