ORIG_HEAD.md

HEAD and ORIG_HEAD

ORIG_HEAD

• ORIG_HEAD stores the previous state of HEAD before executing risky commands.
• It is set by commands that change HEAD by more than one commit (e.g. merge, rebase, reset).
  • ORIG_HEAD is not always set, as it only updates during these specific operations.

HEAD@{1}

• HEAD@{1} refers to the last value of HEAD before the most recent change.
• Unlike ORIG_HEAD, HEAD@{1} is always available.
  • It pulls from the reflog specific to the current branch, tracking the changes made to that branch rather than just HEAD.

Note: @ refers to the current commit that HEAD points to.

Example of Using HEAD@{x}

HEAD@{x} is useful for referencing a specific state from your reflog history. For example:

To reset your branch to the state before the most recent commit:

git reset --hard HEAD@{1}

This will reset the current branch to the commit before the most recent HEAD change, which could be from a commit, merge, or rebase.

To checkout the state of the branch two changes ago:

git checkout HEAD@{2}

This is useful if you want to explore or inspect how the branch looked two changes prior.

To see the reflog history for HEAD:

git reflog

This will show you a list of previous states HEAD has gone through, with the index (HEAD@{0}, HEAD@{1}, etc.) that you can use to reference each state.