Commiting only parts of a file in Mercurial

Let say you have a file and by accident changed two unrelated part of the file. Now it would be nice if one could commit each of the changes in their own changeset.

The solution for Mercurial is an extension called record.

You enable the extension in your hgrc file. You would properly want to do it in the ~/.hgrc file to make it system wide.
Just add:

hgext.record =

Then you just write:

hg record

You might also consider these other extensions:

hgext.fetch =
hgext.churn =
hgext.mq =
hgext.patchbomb =
hgext.graphlog =
hgext.highlight =
bfiles = ~/path_to_bfiles

Installing ec2-ami-tools on AWS Ubuntu 10.04 image

I have just spend a disproportionate amount of time solving this simple question.

It is actually pretty easy: Enable the multiverse reposity, update, and install.

The multiverse repository is enable by editing /etc/apt/sources.list

sudo nano /etc/apt/sources.list

Change:

deb http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid main universe
deb-src http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid main universe
deb http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid-updates main universe
deb-src http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid-updates main universe
deb http://security.ubuntu.com/ubuntu lucid-security main universe
deb-src http://security.ubuntu.com/ubuntu lucid-security main universe

to:

deb http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid main universe multiverse
deb-src http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid main universe multiverse
deb http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid-updates main universe multiverse
deb-src http://eu-west-1.ec2.archive.ubuntu.com/ubuntu/ lucid-updates main universe multiverse
deb http://security.ubuntu.com/ubuntu lucid-security main universe multiverse
deb-src http://security.ubuntu.com/ubuntu lucid-security main universe multiverse

Now run:

sudo apt-get update

and install:

sudo apt-get install ec2-ami-tools