How do I install development tools for 12.10?

Do not copy my commands, you must type them in and use your tab key becuase my kernel may be different than yours. I explain play by play:

Open up a terminal and type:

sudo apt-get update

This update gives your computer a heads up of files you may need. But no files download, only information on what can be downloaded. If you didn't do this first, you may not have the latest link to security updates or the latest versions of software.

As you type, press the tab key, to finish your command. Start typing the command that will install build-essential. Once you get this far stop:

sudo apt-get install linux-headers-

The next part that should appear will be your Linux kernel. So open another terminal and type this:

uname -r

You should see something like this:

3.2.0-23-generic

Now go back to the other terminal and press tab as type. You should see your kernel pop up. Choose that one.

sudo apt-get install linux-headers-3.2.0-23-generic

Now type a space and add build-essential (don't forget use your tab for completion).

sudo apt-get install linux-headers-3.2.0-23-generic build-essential

Now hit enter and files will download that help you compile code.

uname is a command which must be entered at the commandline. So if you open a terminal and type uname it outputs the word Linux. In the command you mentioned you find -r. This is an option to uname. It instructs uname to print the kernel release number. So it will basically print out some numbers (like 3.2.0-41-amd64).

You should enter the command

sudo apt-get install linux-headers-$(uname -r) build-essential

like it is written. The $(something) tells your commandline (better word would be shell) to execute the command something and insert the output of that command.

So in your uname case (assuming that the number I wrote is correct, which might not be in your case) the command which is executed is sudo apt-get install linux-headers-3.2.0-41-amd64 build-essential. Basically you could just look for your kernel version and insert it manually.

As you now see none of your versions is correct. The solution looks a bit different.