Tip #1: KVM and Slackware 8.1

This document is a result of addressing a problem of erratic mouse behavior in the Linux GUI, X, after connecting to a Keyboard, Video, and Mouse (KVM) switch box. Apparently there is a problem with the console based mouse program, "gpm" and X working together when attached to a KVM box. It should be noted that the solution found did not originate with me. It was discovered on a Usenet Newsgroup on the Internet, so credit should go to the Linux community as a whole.

The symptom: Mouse cursor position defaults to bottom left of screen when moving pointer. Mouse clicks spontaneously and erratically. Before I connected the KVM box there was no problem in running gpm with X, so this problem - solution is only a result of connecting to a KVM box.

The specific hardware is an IO Gear 4 port mini KVM switch box. The OS is Slackware Linux 8.1 running KDE 3.0. The mouse is a Logitech wireless optical with wheel. Even though the KVMbox stated it was for a Microsoft operating system, after applying the solution it worked just fine in Linux.

The summary of the solution is to "kill" the gpm driver and disable it in the startup script. In addition, if there is still an issue (with the wheel portion of the mouse) you can edit
XF86Config in the /etc/X11 directory to disable it.

The following is a series of specific steps for accomplishing the task(s):

1. If you are in X, logout and work at the command line as root.
2. Issue the command: "gpm -k" this will stop the console based 
    mouse driver.
3. To disable gpm from starting up at boot up, change directories 
     to /etc/rc.d and list the directory.

Note: In Slackware, there is a specific file called rc.gpm that gets executed in the boot process, other distributions have gpm loading in the rc.local file.

4. To disable the execute bit on rc.gpm, issue the command 
    "chmod 644 rc.gpm"
5. If your using another distribution, edit the rc.local file and put 
     a "#" at the beginning of the line that loads gpm.

This should clear up the erratic behavior of the mouse and make it operational in X. The additional steps included here are in reference to loading a different mouse protocol for wheel 
problems in X.

Note: You should always make a backup copy of the file your editing before you actually make changes. To do this change directories to /etc/X11. Issue the "cp XF86Config XF86Config.lastworking" command, for example.

1. If you are in the /etc/X11 directory edit the "XF86Config" file.
2. Look for the section labeled "Core Pointer's InputDevice section."
     (Slackware 8.1 XF86Config label)
3. There should be line that reads "Option Protocol IMPS/2."
4. Change IMPS/2 to PS/2.

Note: This will disable the wheel but leave the rest of the mouse functions working.

Don't forget to save your changes.

-- Tom Nielsen     <tom45555@cybertime.net>
    Jan 11, 2003

Tip #2:   UNIX/Linux method of copy/paste that works across most applications and the console.

In a Console  or in a GUI  like KDE you can copy and paste if your mouse is enabled and has  3 buttons, or has middle button emulation turned-on.

In a GUI use the following steps: 

1) Hold the left mouse button down and drag the mouse cursor over the text you want to copy.  This selects {or highlights} the text to be copied.  

2) Make the target window or application active and move the insertion point to the target for the paste.

3) Press the middle button to paste the selected text at the insertion point.  For mice that emulate 3 buttons, you press the left & right mouse buttons at the same time to make the middle button.  
    
This method will also work in a Console on distributions that support a mouse.  Text is selected in a similar way,  but pasting only occurs at the active keyboard curser.  As tested in Mandrake 7.0 you can copy/paste from one console another console {i.e.  tty2 to tty3},    You can not copy/paste from a console to a GUI or from a GUI to a Console, however.   Mouse buttons may not be implemented the same way as in a GUI, so you may need to experiment.
    
I've often heard complaints like, "I can't cut & paste from Kedit to Netscape Messenger."  You can copy from any open window to almost any other open window in an x-session by using the this technique.  

In a GUI, one thing to keep in mind however is that the window where the selected text is located needs to remain open and the highlighting must still be in place when you perform the paste.

--Alan Shoemaker  alan@shoemaker.net

June 12, 2000

Tip #3:   HP Printer Performance Architecture {PPA} & Linux

Tim Norman has written a PBM to PPA converter {see: http://www.httptech.com/ppa/ } that takes ghostscript output {PBM} and allows the use of HP 720, 820, and 1000 series printers which are based on Printer Performance Architecture {PPA} protocol.   
   
PPA  is a protocol developed by Hewlett Packard for the series of Deskjet printers {listed above} that moves the low-level processing of the data to the host computer rather than the printer. This allows for a low-cost printer with a small amount of memory and computing power.  However, it comes at the price of compatibility and makes the printer operating system dependant.  Until Tim's work in 1998, HP's decision to develop drivers for Windows 9x only, has resulted in much frustration for Linux users.   As of May 18, 1999 the converter which is provided under GPL { pbm2ppa-0.8.6} does not yet support color printing.

I have been using the converter with my HP-722c and am working on a utility in TCL/TK that makes it *friendlier* under KDE.   The PPA converter allows me to use "the printer I have" with both Linux and Win-9x rather than having to buy a new one.   If you are considering a new printer, a NON-PPA printer is recommended.

--- Dick Foerster,  rdf@rdfoerster.com 
    Feb. 11, 2000