c884862e2fb91831c3962599507b4034d4bcb77e
   1git-checkout(1)
   2===============
   3
   4NAME
   5----
   6git-checkout - Checkout a branch or paths to the working tree
   7
   8SYNOPSIS
   9--------
  10[verse]
  11'git checkout' [-q] [-f] [[--track | --no-track] -b <new_branch> [-l]] [-m] [<branch>]
  12'git checkout' [-f|--ours|--theirs|-m] [<tree-ish>] [--] <paths>...
  13
  14DESCRIPTION
  15-----------
  16
  17When <paths> are not given, this command switches branches by
  18updating the index and working tree to reflect the specified
  19branch, <branch>, and updating HEAD to be <branch> or, if
  20specified, <new_branch>.  Using -b will cause <new_branch> to
  21be created; in this case you can use the --track or --no-track
  22options, which will be passed to `git branch`.
  23
  24When <paths> are given, this command does *not* switch
  25branches.  It updates the named paths in the working tree from
  26the index file, or from a named commit.  In
  27this case, the `-b` options is meaningless and giving
  28either of them results in an error.  <tree-ish> argument can be
  29used to specify a specific tree-ish (i.e. commit, tag or tree)
  30to update the index for the given paths before updating the
  31working tree.
  32
  33The index may contain unmerged entries after a failed merge.  By
  34default, if you try to check out such an entry from the index, the
  35checkout operation will fail and nothing will be checked out.
  36Using -f will ignore these unmerged entries.  The contents from a
  37specific side of the merge can be checked out of the index by
  38using --ours or --theirs.  With -m, changes made to the working tree
  39file can be discarded to recreate the original conflicted merge result.
  40
  41OPTIONS
  42-------
  43-q::
  44        Quiet, suppress feedback messages.
  45
  46-f::
  47        When switching branches, proceed even if the index or the
  48        working tree differs from HEAD.  This is used to throw away
  49        local changes.
  50+
  51When checking out paths from the index, do not fail upon unmerged
  52entries; instead, unmerged entries are ignored.
  53
  54--ours::
  55--theirs::
  56        When checking out paths from the index, check out stage #2
  57        ('ours') or #3 ('theirs') for unmerged paths.
  58
  59-b::
  60        Create a new branch named <new_branch> and start it at
  61        <branch>.  The new branch name must pass all checks defined
  62        by linkgit:git-check-ref-format[1].  Some of these checks
  63        may restrict the characters allowed in a branch name.
  64
  65-t::
  66--track::
  67        When creating a new branch, set up configuration so that 'git-pull'
  68        will automatically retrieve data from the start point, which must be
  69        a branch. Use this if you always pull from the same upstream branch
  70        into the new branch, and if you don't want to use "git pull
  71        <repository> <refspec>" explicitly. This behavior is the default
  72        when the start point is a remote branch. Set the
  73        branch.autosetupmerge configuration variable to `false` if you want
  74        'git-checkout' and 'git-branch' to always behave as if '--no-track' were
  75        given. Set it to `always` if you want this behavior when the
  76        start-point is either a local or remote branch.
  77
  78--no-track::
  79        Ignore the branch.autosetupmerge configuration variable.
  80
  81-l::
  82        Create the new branch's reflog.  This activates recording of
  83        all changes made to the branch ref, enabling use of date
  84        based sha1 expressions such as "<branchname>@\{yesterday}".
  85
  86-m::
  87        When switching branches,
  88        if you have local modifications to one or more files that
  89        are different between the current branch and the branch to
  90        which you are switching, the command refuses to switch
  91        branches in order to preserve your modifications in context.
  92        However, with this option, a three-way merge between the current
  93        branch, your working tree contents, and the new branch
  94        is done, and you will be on the new branch.
  95+
  96When a merge conflict happens, the index entries for conflicting
  97paths are left unmerged, and you need to resolve the conflicts
  98and mark the resolved paths with `git add` (or `git rm` if the merge
  99should result in deletion of the path).
 100+
 101When checking out paths from the index, this option lets you recreate
 102the conflicted merge in the specified paths.
 103
 104<new_branch>::
 105        Name for the new branch.
 106
 107<branch>::
 108        Branch to checkout; may be any object ID that resolves to a
 109        commit.  Defaults to HEAD.
 110+
 111When this parameter names a non-branch (but still a valid commit object),
 112your HEAD becomes 'detached'.
 113
 114
 115Detached HEAD
 116-------------
 117
 118It is sometimes useful to be able to 'checkout' a commit that is
 119not at the tip of one of your branches.  The most obvious
 120example is to check out the commit at a tagged official release
 121point, like this:
 122
 123------------
 124$ git checkout v2.6.18
 125------------
 126
 127Earlier versions of git did not allow this and asked you to
 128create a temporary branch using `-b` option, but starting from
 129version 1.5.0, the above command 'detaches' your HEAD from the
 130current branch and directly point at the commit named by the tag
 131(`v2.6.18` in the above example).
 132
 133You can use usual git commands while in this state.  You can use
 134`git reset --hard $othercommit` to further move around, for
 135example.  You can make changes and create a new commit on top of
 136a detached HEAD.  You can even create a merge by using `git
 137merge $othercommit`.
 138
 139The state you are in while your HEAD is detached is not recorded
 140by any branch (which is natural --- you are not on any branch).
 141What this means is that you can discard your temporary commits
 142and merges by switching back to an existing branch (e.g. `git
 143checkout master`), and a later `git prune` or `git gc` would
 144garbage-collect them.  If you did this by mistake, you can ask
 145the reflog for HEAD where you were, e.g.
 146
 147------------
 148$ git log -g -2 HEAD
 149------------
 150
 151
 152EXAMPLES
 153--------
 154
 155. The following sequence checks out the `master` branch, reverts
 156the `Makefile` to two revisions back, deletes hello.c by
 157mistake, and gets it back from the index.
 158+
 159------------
 160$ git checkout master             <1>
 161$ git checkout master~2 Makefile  <2>
 162$ rm -f hello.c
 163$ git checkout hello.c            <3>
 164------------
 165+
 166<1> switch branch
 167<2> take out a file out of other commit
 168<3> restore hello.c from HEAD of current branch
 169+
 170If you have an unfortunate branch that is named `hello.c`, this
 171step would be confused as an instruction to switch to that branch.
 172You should instead write:
 173+
 174------------
 175$ git checkout -- hello.c
 176------------
 177
 178. After working in a wrong branch, switching to the correct
 179branch would be done using:
 180+
 181------------
 182$ git checkout mytopic
 183------------
 184+
 185However, your "wrong" branch and correct "mytopic" branch may
 186differ in files that you have locally modified, in which case,
 187the above checkout would fail like this:
 188+
 189------------
 190$ git checkout mytopic
 191fatal: Entry 'frotz' not uptodate. Cannot merge.
 192------------
 193+
 194You can give the `-m` flag to the command, which would try a
 195three-way merge:
 196+
 197------------
 198$ git checkout -m mytopic
 199Auto-merging frotz
 200------------
 201+
 202After this three-way merge, the local modifications are _not_
 203registered in your index file, so `git diff` would show you what
 204changes you made since the tip of the new branch.
 205
 206. When a merge conflict happens during switching branches with
 207the `-m` option, you would see something like this:
 208+
 209------------
 210$ git checkout -m mytopic
 211Auto-merging frotz
 212merge: warning: conflicts during merge
 213ERROR: Merge conflict in frotz
 214fatal: merge program failed
 215------------
 216+
 217At this point, `git diff` shows the changes cleanly merged as in
 218the previous example, as well as the changes in the conflicted
 219files.  Edit and resolve the conflict and mark it resolved with
 220`git add` as usual:
 221+
 222------------
 223$ edit frotz
 224$ git add frotz
 225------------
 226
 227
 228Author
 229------
 230Written by Linus Torvalds <torvalds@osdl.org>
 231
 232Documentation
 233--------------
 234Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
 235
 236GIT
 237---
 238Part of the linkgit:git[1] suite