git - Update forked project on GitHub

Question

Let's say a repository from which I clone (and only read-only for me) is:

git@github.com:secret_project/dev.git  branch: dev

I forked project and URL:

git@github.com:secret_user/Dde.git

(Which I have full access to: read+write)

But someone updated git@github.com:secret_project/dev.git from another forked version.

Let's say file changed on

git@github.com:secret_project/dev.git  (test.txt)
content:
hi!

But my forked project has test.txt file with content:

hi

So how do I update the forked project locally and in my repository?

Which commands should I use? And please make an example with my showed repositories...

Answer 1

You should add the remote address for the original repository 'upstream' to your local repository (which is a clone of your Dde.git fork):

git remote add upstream git://github.com/secret_project/dev.git # public read-only URL

That will allow you to pull 'upstream' into your own branch (merging and resolving any merge conflict in test.txt).
Then you will push your local branch to your Dde GitHub repository.

See GitHub help page: "Working with remotes" for more details.