How to tell if your head is detached in git?

Question

How do you tell if your head has been detached in git? I have a feeling that might be the root of my problem.

Answer 1

An alternative useful for scripts, without having to deal with $GITDIR is

git rev-parse --abbrev-ref --symbolic-full-name HEAD

This gives me HEAD for a detached head, or the branch name on the other case.