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After your Pull-Request has been accepted, you will need to syncrhonize your fork with the upstream. Instructions for doing this are available here: https://help.github.com/en/github/collaborating-with-issues-and-pull-requests/syncing-a-fork. Often, a fork will diverge too much from the upstream repository to keep in synchronization properly. In this case, feel free to create a new private for, using a new name for the forked repository, of course.
It is a common practice to delete a fork after the pull-request has been closed. Github even supports a special shortcut to delete your fork. After the you PR has been closed, go to the https://github.com/apache/incubator-nuttx/pull/NN page (where NN is the PR number that was assigned to your pull request). You will see this message on that page:
Pull request closed
If you wish, you can delete this fork of apache/incubator-nuttx.
Simply clink the "Fork Settings" button and confirm that your really want to delete your fork.
REVISIT: By emailing a patch: Describe how to make the relevant patch(es) (git format-patch) and send them to dev@nuttx.apache.org.
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