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git-checkout - Checkout and switch to a branch
SYNOPSIS
git-checkout [-f] [-b <new_branch> [-l]] [-m] [<branch>]
git-checkout [-m] [<branch>] <paths>...
DESCRIPTION
When <paths> are not given, this command switches branches by updating the index and working tree to reflect the
specified branch, <branch>, and updating HEAD to be <branch> or, if specified, <new_branch>. Using -b will cause
<new_branch> to be created.
When <paths> are given, this command does not switch branches. It updates the named paths in the working tree
from the index file (i.e. it runs git-checkout-index -f -u). In this case, -f and -b options are meaningless and
giving either of them results in an error. <branch> argument can be used to specify a specific tree-ish to update
the index for the given paths before updating the working tree.
OPTIONS
-f
Force a re-read of everything.
-b
Create a new branch named <new_branch> and start it at <branch>. The new branch name must pass all checks
defined by git-check-ref-format(1). Some of these checks may restrict the characters allowed in a branch
name.
-l
Create the new branch's ref log. This activates recording of all changes to made the branch ref, enabling use
of date
-m
If you have local modifications to one or more files that are different between the current branch and the
branch to which you are switching, the command refuses to switch branches in order to preserve your
modifications in context. However, with this option, a three-way merge between the current branch, your
working tree contents, and the new branch is done, and you will be on the new branch.
When a merge conflict happens, the index entries for conflicting paths are left unmerged, and you need to
resolve the conflicts and mark the resolved paths with git update-index.
<new_branch>
Name for the new branch.
<branch>
Branch to checkout; may be any object ID that resolves to a commit. Defaults to HEAD.
EXAMPLES
1. The following sequence checks out the master branch, reverts the Makefile to two revisions back, deletes
hello.c by mistake, and gets it back from the index.
$ git checkout master (1)
$ git checkout master~2 Makefile (2)
$ rm -f hello.c
$ git checkout hello.c (3)
1. switch branch
2. take out a file out of other commit
3. restore hello.c from HEAD of current branch
If you have an unfortunate branch that is named hello.c, this step would be confused as an instruction to switch
to that branch. You should instead write:
$ git checkout -- hello.c
2. After working in a wrong branch, switching to the correct branch would be done using:
$ git checkout mytopic
However, your "wrong" branch and correct "mytopic" branch may differ in files that you have locally modified, in
which case, the above checkout would fail like this:
$ git checkout mytopic
fatal: Entry 'frotz' not uptodate. Cannot merge.
You can give the -m flag to the command, which would try a three-way merge:
$ git checkout -m mytopic
Auto-merging frotz
After this three-way merge, the local modifications are not registered in your index file, so git diff would show
you what changes you made since the tip of the new branch.
3. When a merge conflict happens during switching branches with the -m option, you would see something like
this:
$ git checkout -m mytopic
Auto-merging frotz
merge: warning: conflicts during merge
ERROR: Merge conflict in frotz
fatal: merge program failed
At this point, git diff shows the changes cleanly merged as in the previous example, as well as the changes in
the conflicted files. Edit and resolve the conflict and mark it resolved with git update-index as usual:
$ edit frotz
$ git update-index frotz
DOCUMENTATION
Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
GIT
Part of the git(7) suite
CATEGORY