As a beginner on commande lines, I failed at the very first step to upgrade my stable version (etch) to unstable version before installing Kdenlive.
typed "etc/apt/sources.list" as "su" on agraphic mode on gnome : "permission denied"appeared.
As single user, from grub I had the same same answer.
So, I don't know how to add the following lines "deb-src .... deb http ....."
What is wrong ?
Some please can tell me ?