"Linux Gazette...making Linux just a little more fun! "

Normally, users of PS/2 type mice have a problem in that a PS/2 type mouse cannot simultaneously be shared among different applications such as gpm (selection) and XFree86. That was until the discovery of a tiny utility called, mconv2. Mconv2 allows several programs to use a PS/2 type mouse at the same time.

The mconv2 utility also supports the use of a PS/2 type mouse with applications that do not understand the PS/2 mouse protocol, but understand the microsoft serial mouse protocol (such as svgalib). This document only descrdibes the sharing of the PS/2 type mouse - not its use as a microsoft type mouse - for information on this, read the README file included with the mconv2 distribution.

Installing and using mconv2 is VERY simple :-

1. Getting mconv2
   Mconv2 can be downloaded from a variety of Linux archive sites. I got my copy from
   
   http://sunsite.unc.edu/pub/Linux/system/Misc/mconv2.tar.gz
   

2. Extracting Distribution
   Mconv2 is distributed as a compressed (gz) tar archive. Hence, it needs to be extraceted in a suitable directory before it can be installed. I used the /usr/src directory, but any directory will do. Copy the mconv2 distribution file (mconv2.tar.gz) to the selected working directory, eg. /usr/src (or the directory you care to extract it in) as follows :-
   

       cp mconv2.tar.gz /usr/src
     

   Go to the working directory and extract the mconv2 archive, as follows :-
   

       cd /usr/src
       tar -zxvf mconv2.tar.gz 
     

   This will create a subdirectory called mconv2 containing,
   • the mconv2 source code - mconv2.c
   • a binary compiled mconv2 executable - mconv2
   • supporting documentation files - mconv2.lsm and README
   
   

3. To compilie mconv2, or not
   Together with the source and supporting documentation, the mconv2 distribution also comes with a pre-built binary of the program. This can be used as-is or the program can be recompiled very easily, as follows :-
   

       gcc -O2 -o mconv2 mconv2.c
     

   
   

4. Installing the mconv2 binary Copy the pre-built, or newly made, mconv2 binary file (mconv2) to an appropriate directory for executing binarys from - I use /usr/local/bin.
   

       cp mconv2 /usr/local/bin 
     

5. Builiding a fifo for the PS/2 mouse
   Create a fifo device (pseudo mouse driver) for the PS/2 mouse, as follows :-
   

       mkfifo -m 666 /dev/ps2mouse
     

   
   

6. Using mconv2
   Before running any programs using the PS/2 mouse, mconv2 should be run first and other programs needing the mouse, should be configured to use the PS/2 pseudo device, /dev/ps2mouse. It is probably best, to start mconv2 from the /etc/rc.d.rc.local file with the following command :-

       echo -n "Runnig mconv2 .... "
       /usr/local/bin/mconv2 /dev/psaux -ps2 /dev/ps2mouse &
       echo "Done"
     

   NOTE :- this assumes your original mouse device was /dev/psaux
   

7. Configuring other programms to use mconv2
   As mentioned in the point above, other programs requiring the PS/2 mouse must be configured to use the mconv2 pseudo mouse device - /dev/ps2mouse.
   

   Examples :-
   

   • To set up gpm, to use this pseudo device, invoke it as follows :-

         gpm -t ps2 -m /dev/ps2mouse &
       

     NOTE :- the -m option tells gpm what mouse device to use
     

   • To set up XFree86 to use the pseudo device, modify the Pointer section of the XF86Config file to set the mouse device to /dev/ps2mouse as follows :-

         Section "Pointer"
           Protocol    "PS/2"
           Device      "/dev/ps2mouse"
       

Nic Tjirkalli