On Wed, 12 Mar 2003 [EMAIL PROTECTED] wrote: > In theory, is there any limit to the number of mice that can be handled > simultaneously in XF86? I can't think of a reason why one would want 4 or 5 > people controlling the same pointer, but would be fun to try.
No limit, at least under 2.4.19 and greater kernels. Here's actually what happens (I examined the kernel code a few months ago for a strange project --- I even modified the kernel code to try to do something similar with keyboards, but stopped when I realised I'd have to replicate all the kernel keyboard buffer code and scancode translation logic). When you plug a new USB mouse into your computer the kernel creates a file /dev/mice/mouse? (where ? is a number). If you ignore this file then all events from that mouse get redirected to /dev/misc/psaux (the standard PS/2 mouse device). If you tell X that your mouse device is /dev/misc/psaux then you can use as many USB mice as you want to. If you open and read that file (/dev/mice/mouse?) then you get the input stream from the mouse, and the mouse events are no longer sent to /dev/misc/psaux ooh, I'm assuming you're using devfs. Otherwise I have no idea the file names, and things could easily work differently. > Also, does a usb mouse provide a better performance than the equivalent > mouse, in a PS/2 port? I would have thought that any differences would have > been almost indiscernible. USB mice update on the screen many times more per second than PS/2 mice. It's especially noticeable when moving the mouse in circles, and very very noticeable when playing games like Quake. Tim Wright Assistant Lecturer Department of Computer Science University of Canterbury http://www.cosc.canterbury.ac.nz/~tnw13
