[R] Timer in R?

[Jim Lemon]

Johnathan Williams wrote:

> Would anyone be so kind as to write a routine to time 
> mouse button presses in R to the nearest millisecond?
>
> If R had a timer of this kind and a few basic screen
> handling routines (to write characters or graphics of
> different sizes and colours at precise times) then it
> would make it easy to use it for on-line data analysis
> of data to control EEG experiments.

I do this under DOS for a battery of human performance tests. However, it 
requires taking over the system clock _and_ the keyboard interrupt to time 
keypresses to the nearest millisecond (and you can get a bit more than 
that if you want). If anyone knows about how to do this under Linux, I 
would love to port these tests over.

Jim