Is the commandline svn by default installed in Ubuntu 9.10? or do I have to install it form somewhere. I have made my external HDD a Subversion server and I have to commit / update the changes there. So suggest me how to get this done? I mean how I could first mount the HDD on my Ubuntu partition and then execute the svn command to checkin and checkout the sources.
Did you try opening a terminal and typing "svn"? If you have not tried this, go and do it now. Ubuntu is really nice in that if the command you are trying to run is not installed, and if it recognizes the command, it will tell you how you can install the package that contains the command.