a9ca2f552017cc592c8ff6b553bf0bbf875646a0
   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] [<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.
  39
  40OPTIONS
  41-------
  42-q::
  43        Quiet, suppress feedback messages.
  44
  45-f::
  46        When switching branches, proceed even if the index or the
  47        working tree differs from HEAD.  This is used to throw away
  48        local changes.
  49+
  50When checking out paths from the index, do not fail upon unmerged
  51entries; instead, unmerged entries are ignored.
  52
  53--ours::
  54--theirs::
  55        When checking out paths from the index, check out stage #2
  56        ('ours') or #3 ('theirs') for unmerged paths.
  57
  58-b::
  59        Create a new branch named <new_branch> and start it at
  60        <branch>.  The new branch name must pass all checks defined
  61        by linkgit:git-check-ref-format[1].  Some of these checks
  62        may restrict the characters allowed in a branch name.
  63
  64-t::
  65--track::
  66        When creating a new branch, set up configuration so that 'git-pull'
  67        will automatically retrieve data from the start point, which must be
  68        a branch. Use this if you always pull from the same upstream branch
  69        into the new branch, and if you don't want to use "git pull
  70        <repository> <refspec>" explicitly. This behavior is the default
  71        when the start point is a remote branch. Set the
  72        branch.autosetupmerge configuration variable to `false` if you want
  73        'git-checkout' and 'git-branch' to always behave as if '--no-track' were
  74        given. Set it to `always` if you want this behavior when the
  75        start-point is either a local or remote branch.
  76
  77--no-track::
  78        Ignore the branch.autosetupmerge configuration variable.
  79
  80-l::
  81        Create the new branch's reflog.  This activates recording of
  82        all changes made to the branch ref, enabling use of date
  83        based sha1 expressions such as "<branchname>@\{yesterday}".
  84
  85-m::
  86        If you have local modifications to one or more files that
  87        are different between the current branch and the branch to
  88        which you are switching, the command refuses to switch
  89        branches in order to preserve your modifications in context.
  90        However, with this option, a three-way merge between the current
  91        branch, your working tree contents, and the new branch
  92        is done, and you will be on the new branch.
  93+
  94When a merge conflict happens, the index entries for conflicting
  95paths are left unmerged, and you need to resolve the conflicts
  96and mark the resolved paths with `git add` (or `git rm` if the merge
  97should result in deletion of the path).
  98
  99<new_branch>::
 100        Name for the new branch.
 101
 102<branch>::
 103        Branch to checkout; may be any object ID that resolves to a
 104        commit.  Defaults to HEAD.
 105+
 106When this parameter names a non-branch (but still a valid commit object),
 107your HEAD becomes 'detached'.
 108
 109
 110Detached HEAD
 111-------------
 112
 113It is sometimes useful to be able to 'checkout' a commit that is
 114not at the tip of one of your branches.  The most obvious
 115example is to check out the commit at a tagged official release
 116point, like this:
 117
 118------------
 119$ git checkout v2.6.18
 120------------
 121
 122Earlier versions of git did not allow this and asked you to
 123create a temporary branch using `-b` option, but starting from
 124version 1.5.0, the above command 'detaches' your HEAD from the
 125current branch and directly point at the commit named by the tag
 126(`v2.6.18` in the above example).
 127
 128You can use usual git commands while in this state.  You can use
 129`git reset --hard $othercommit` to further move around, for
 130example.  You can make changes and create a new commit on top of
 131a detached HEAD.  You can even create a merge by using `git
 132merge $othercommit`.
 133
 134The state you are in while your HEAD is detached is not recorded
 135by any branch (which is natural --- you are not on any branch).
 136What this means is that you can discard your temporary commits
 137and merges by switching back to an existing branch (e.g. `git
 138checkout master`), and a later `git prune` or `git gc` would
 139garbage-collect them.  If you did this by mistake, you can ask
 140the reflog for HEAD where you were, e.g.
 141
 142------------
 143$ git log -g -2 HEAD
 144------------
 145
 146
 147EXAMPLES
 148--------
 149
 150. The following sequence checks out the `master` branch, reverts
 151the `Makefile` to two revisions back, deletes hello.c by
 152mistake, and gets it back from the index.
 153+
 154------------
 155$ git checkout master             <1>
 156$ git checkout master~2 Makefile  <2>
 157$ rm -f hello.c
 158$ git checkout hello.c            <3>
 159------------
 160+
 161<1> switch branch
 162<2> take out a file out of other commit
 163<3> restore hello.c from HEAD of current branch
 164+
 165If you have an unfortunate branch that is named `hello.c`, this
 166step would be confused as an instruction to switch to that branch.
 167You should instead write:
 168+
 169------------
 170$ git checkout -- hello.c
 171------------
 172
 173. After working in a wrong branch, switching to the correct
 174branch would be done using:
 175+
 176------------
 177$ git checkout mytopic
 178------------
 179+
 180However, your "wrong" branch and correct "mytopic" branch may
 181differ in files that you have locally modified, in which case,
 182the above checkout would fail like this:
 183+
 184------------
 185$ git checkout mytopic
 186fatal: Entry 'frotz' not uptodate. Cannot merge.
 187------------
 188+
 189You can give the `-m` flag to the command, which would try a
 190three-way merge:
 191+
 192------------
 193$ git checkout -m mytopic
 194Auto-merging frotz
 195------------
 196+
 197After this three-way merge, the local modifications are _not_
 198registered in your index file, so `git diff` would show you what
 199changes you made since the tip of the new branch.
 200
 201. When a merge conflict happens during switching branches with
 202the `-m` option, you would see something like this:
 203+
 204------------
 205$ git checkout -m mytopic
 206Auto-merging frotz
 207merge: warning: conflicts during merge
 208ERROR: Merge conflict in frotz
 209fatal: merge program failed
 210------------
 211+
 212At this point, `git diff` shows the changes cleanly merged as in
 213the previous example, as well as the changes in the conflicted
 214files.  Edit and resolve the conflict and mark it resolved with
 215`git add` as usual:
 216+
 217------------
 218$ edit frotz
 219$ git add frotz
 220------------
 221
 222
 223Author
 224------
 225Written by Linus Torvalds <torvalds@osdl.org>
 226
 227Documentation
 228--------------
 229Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
 230
 231GIT
 232---
 233Part of the linkgit:git[1] suite