x2x: share mouse and keyboard over ssh

For quote some time I have been using x2x to have single keyboard and mouse for multiple machines (EeePC or third monitor at work), but I had problem with selection buffers. x2x was written for scenario where all X servers are listening to network connections, so if you had two machines klin and t42 and you wanted to use keyboard and mouse on klin you would have to do something like this:

dpavlin@t42:~$ xhost klin

dpavlin@klin:~$ x2x -to klin:0 -west

However, recent Debian systems are not listening to TCP connections, so you will have to modify xserverrc for this to work:

dpavlin@t42:~$ cat /etc/X11/xinit/xserverrc 
#!/bin/sh

exec /usr/bin/X11/X #-nolisten tcp

However, it's much nicer to depend on ssh X11 forwarding to provide encryption using:

dpavlin@klin:~$ ssh -X t42 x2x -to :0 -west

To finish this post, I have to include small patch which allows to switch copy/paste direction (which I don't need any more, but it proved useful in at least one case):

diff -r 2ce6789a43da x2x.c
--- a/x2x.c     Tue Mar 18 22:47:34 2008 +0600
+++ b/x2x.c     Tue Nov 24 14:08:16 2009 +0100
@@ -1125,7 +1125,7 @@
       if (doSel) {
         // pDpyInfo->initialClipboardSeen = False;
         pDpyInfo->winSelText = NULL;
-        pDpyInfo->hwndNextViewer = SetClipboardViewer(pDpyInfo->edgewindow);
+        pDpyInfo->hwndNextViewer = SetClipboardViewer(pDpyInfo->bigwindow);
       }
 
       pDpyInfo->onedge = 0;