Track someone's GitHub repo in a branch

Question

I'm pretty new to Git, and like it a lot so far, but am not sure what do do here.

I've forked a github project, and am currently in the process of porting it to another language. For reference, I've created a branch of the code as it was when I made the fork. My problem now is that the original project has been updated, and I can't figure out how to pull those changes into my branch from the original master (because 'origin' points to my github project).

Follow-up question for my own education, what command will the owner of the original project have to run in order to pull a change in from my branch into his master branch?

EDIT: These answers work when I run them from my own 'master' branch, but not when I run them from my 'tracking' branch (I'm using the term loosely here because I know of a git command of the same name. Not sure what it does, though).

When I'm in my non-master branch, and run git fetch upstream, nothing happens. When I try git fetch upstream:master, it says

ssh: upstream: no address associated with name
fatal: The remote end hung up unexpectedly

Answer 1

You can add the original repo using git remote:

$ git remote add upstream http://github.com/user/repo.git

(You can call it something other than upstream if you want, but that's the name you'll use to refer to the remote.)

To get updates, just run:

$ git fetch upstream

In order to get the changes from your repo into the upstream repo, the maintainer will have to add your repo as a remote, and then pull the changes:

$ git remote add drhorrible http://github.com/youruser/yourrrepo.git
$ git pull drhorrible your-branch:master

Or, if the upstream maintainer doesn't want to add your repo as a remote, he can reference it directly:

$ git pull http://github.com/youruser/yourrepo.git your-branch:master

Answer 2

You can add it to your list of remote repos and fetch/pull from it

$ git remote add first-repo-name git://github.com/first-repo-name/repo.git
$ git fetch first-repo-name
# or:
$ git pull first-repo-name

the git pull will actually merge the first-repo-name master branch to your master branch (if you are currently in that branch)

what command will the owner of the original project have to run in order to pull a change in from my branch into his master branch?

On the GitHub side, this won't be an actual command, but the result of a pull request you would have initiated.

_{(source: skitch.com)}

Technically, he could add your forked repo as a remote repo on his local repo (like you did above), but if his repo is heavily forked, this becomes un-practical, hence the central "pull requests" mechanism.