git-checkout.html - external/gitster/git-htmldocs - Git at Google

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 </style>
 <title>git-checkout(1)</title>
 </head>
 <body>
 <div id="header">
 <h1>
 git-checkout(1) Manual Page
 </h1>
 <h2>NAME</h2>
 <div class="sectionbody">
 <p>git-checkout -
  Checkout and switch to a branch
 </p>
 </div>
 </div>
 <h2>SYNOPSIS</h2>
 <div class="sectionbody">
 <div class="verseblock">
 <div class="content"><em>git-checkout</em> [-q] [-f] [[--track | --no-track] -b &lt;new_branch&gt; [-l]] [-m] [&lt;branch&gt;]
 <em>git-checkout</em> [&lt;tree-ish&gt;] &lt;paths&gt;&#8230;</div></div>
 </div>
 <h2>DESCRIPTION</h2>
 <div class="sectionbody">
 <p>When &lt;paths&gt; are not given, this command switches branches by
 updating the index and working tree to reflect the specified
 branch, &lt;branch&gt;, and updating HEAD to be &lt;branch&gt; or, if
 specified, &lt;new_branch&gt;. Using -b will cause &lt;new_branch&gt; to
 be created; in this case you can use the --track or --no-track
 options, which will be passed to <tt>git branch</tt>.</p>
 <p>When &lt;paths&gt; are given, this command does <strong>not</strong> switch
 branches. It updates the named paths in the working tree from
 the index file (i.e. it runs <tt>git-checkout-index -f -u</tt>), or
 from a named commit. In
 this case, the <tt>-f</tt> and <tt>-b</tt> options are meaningless and giving
 either of them results in an error. &lt;tree-ish&gt; argument can be
 used to specify a specific tree-ish (i.e. commit, tag or tree)
 to update the index for the given paths before updating the
 working tree.</p>
 </div>
 <h2>OPTIONS</h2>
 <div class="sectionbody">
 <dl>
 <dt>
 -q
 </dt>
 <dd>
 <p>
  Quiet, suppress feedback messages.
 </p>
 </dd>
 <dt>
 -f
 </dt>
 <dd>
 <p>
  Proceed even if the index or the working tree differs
  from HEAD. This is used to throw away local changes.
 </p>
 </dd>
 <dt>
 -b
 </dt>
 <dd>
 <p>
  Create a new branch named &lt;new_branch&gt; and start it at
  &lt;branch&gt;. The new branch name must pass all checks defined
  by <a href="git-check-ref-format.html">git-check-ref-format(1)</a>. Some of these checks
  may restrict the characters allowed in a branch name.
 </p>
 </dd>
 <dt>
 --track
 </dt>
 <dd>
 <p>
  When -b is given and a branch is created off a remote branch,
  set up configuration so that git-pull will automatically
  retrieve data from the remote branch. Use this if you always
  pull from the same remote branch into the new branch, or if you
  don't want to use "git pull &lt;repository&gt; &lt;refspec&gt;" explicitly. Set the
  branch.autosetupmerge configuration variable to true if you
  want git-checkout and git-branch to always behave as if
  <em>--track</em> were given.
 </p>
 </dd>
 <dt>
 --no-track
 </dt>
 <dd>
 <p>
  When -b is given and a branch is created off a remote branch,
  set up configuration so that git-pull will not retrieve data
  from the remote branch, ignoring the branch.autosetupmerge
  configuration variable.
 </p>
 </dd>
 <dt>
 -l
 </dt>
 <dd>
 <p>
  Create the new branch's reflog. This activates recording of
  all changes made to the branch ref, enabling use of date
  based sha1 expressions such as "&lt;branchname&gt;@{yesterday}".
 </p>
 </dd>
 <dt>
 -m
 </dt>
 <dd>
 <p>
  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.
 </p>
 <p>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 <tt>git add</tt> (or <tt>git rm</tt> if the merge
 should result in deletion of the path).</p>
 </dd>
 <dt>
 &lt;new_branch&gt;
 </dt>
 <dd>
 <p>
  Name for the new branch.
 </p>
 </dd>
 <dt>
 &lt;branch&gt;
 </dt>
 <dd>
 <p>
  Branch to checkout; may be any object ID that resolves to a
  commit. Defaults to HEAD.
 </p>
 <p>When this parameter names a non-branch (but still a valid commit object),
 your HEAD becomes <em>detached</em>.</p>
 </dd>
 </dl>
 </div>
 <h2>Detached HEAD</h2>
 <div class="sectionbody">
 <p>It is sometimes useful to be able to <em>checkout</em> a commit that is
 not at the tip of one of your branches. The most obvious
 example is to check out the commit at a tagged official release
 point, like this:</p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout v2.6.18</tt></pre>
 </div></div>
 <p>Earlier versions of git did not allow this and asked you to
 create a temporary branch using <tt>-b</tt> option, but starting from
 version 1.5.0, the above command <em>detaches</em> your HEAD from the
 current branch and directly point at the commit named by the tag
 (<tt>v2.6.18</tt> in the above example).</p>
 <p>You can use usual git commands while in this state. You can use
 <tt>git-reset --hard $othercommit</tt> to further move around, for
 example. You can make changes and create a new commit on top of
 a detached HEAD. You can even create a merge by using <tt>git
 merge $othercommit</tt>.</p>
 <p>The state you are in while your HEAD is detached is not recorded
 by any branch (which is natural --- you are not on any branch).
 What this means is that you can discard your temporary commits
 and merges by switching back to an existing branch (e.g. <tt>git
 checkout master</tt>), and a later <tt>git prune</tt> or <tt>git gc</tt> would
 garbage-collect them. If you did this by mistake, you can ask
 the reflog for HEAD where you were, e.g.</p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git log -g -2 HEAD</tt></pre>
 </div></div>
 </div>
 <h2>EXAMPLES</h2>
 <div class="sectionbody">
 <ol>
 <li>
 <p>
 The following sequence checks out the <tt>master</tt> branch, reverts
 the <tt>Makefile</tt> to two revisions back, deletes hello.c by
 mistake, and gets it back from the index.
 </p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout master <b>(1)</b>
 $ git checkout master~2 Makefile <b>(2)</b>
 $ rm -f hello.c
 $ git checkout hello.c <b>(3)</b></tt></pre>
 </div></div>
 <ol>
 <li>
 <p>
 switch branch
 </p>
 </li>
 <li>
 <p>
 take out a file out of other commit
 </p>
 </li>
 <li>
 <p>
 restore hello.c from HEAD of current branch
 </p>
 <p>If you have an unfortunate branch that is named <tt>hello.c</tt>, this
 step would be confused as an instruction to switch to that branch.
 You should instead write:</p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout -- hello.c</tt></pre>
 </div></div>
 </li>
 </ol>
 </li>
 <li>
 <p>
 After working in a wrong branch, switching to the correct
 branch would be done using:
 </p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout mytopic</tt></pre>
 </div></div>
 <p>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:</p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout mytopic
 fatal: Entry 'frotz' not uptodate. Cannot merge.</tt></pre>
 </div></div>
 <p>You can give the <tt>-m</tt> flag to the command, which would try a
 three-way merge:</p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout -m mytopic
 Auto-merging frotz</tt></pre>
 </div></div>
 <p>After this three-way merge, the local modifications are _not_
 registered in your index file, so <tt>git diff</tt> would show you what
 changes you made since the tip of the new branch.</p>
 </li>
 <li>
 <p>
 When a merge conflict happens during switching branches with
 the <tt>-m</tt> option, you would see something like this:
 </p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ git checkout -m mytopic
 Auto-merging frotz
 merge: warning: conflicts during merge
 ERROR: Merge conflict in frotz
 fatal: merge program failed</tt></pre>
 </div></div>
 <p>At this point, <tt>git diff</tt> 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
 <tt>git add</tt> as usual:</p>
 <div class="listingblock">
 <div class="content">
 <pre><tt>$ edit frotz
 $ git add frotz</tt></pre>
 </div></div>
 </li>
 </ol>
 </div>
 <h2>Author</h2>
 <div class="sectionbody">
 <p>Written by Linus Torvalds &lt;torvalds@osdl.org&gt;</p>
 </div>
 <h2>Documentation</h2>
 <div class="sectionbody">
 <p>Documentation by Junio C Hamano and the git-list &lt;git@vger.kernel.org&gt;.</p>
 </div>
 <h2>GIT</h2>
 <div class="sectionbody">
 <p>Part of the <a href="git.html">git(7)</a> suite</p>
 </div>
 <div id="footer">
 <div id="footer-text">
 Last updated 07-Jan-2008 07:50:05 UTC
 </div>
 </div>
 </body>
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	<title>git-checkout(1)</title>
	</head>
	<body>
	<div id="header">
	<h1>
	git-checkout(1) Manual Page
	</h1>
	<h2>NAME</h2>
	<div class="sectionbody">
	<p>git-checkout -
	Checkout and switch to a branch
	</p>
	</div>
	</div>
	<h2>SYNOPSIS</h2>
	<div class="sectionbody">
	<div class="verseblock">
	<div class="content"><em>git-checkout</em> [-q] [-f] [[--track \| --no-track] -b <new_branch> [-l]] [-m] [<branch>]
	<em>git-checkout</em> [<tree-ish>] <paths>…</div></div>
	</div>
	<h2>DESCRIPTION</h2>
	<div class="sectionbody">
	<p>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; in this case you can use the --track or --no-track
	options, which will be passed to <tt>git branch</tt>.</p>
	<p>When <paths> are given, this command does <strong>not</strong> switch
	branches. It updates the named paths in the working tree from
	the index file (i.e. it runs <tt>git-checkout-index -f -u</tt>), or
	from a named commit. In
	this case, the <tt>-f</tt> and <tt>-b</tt> options are meaningless and giving
	either of them results in an error. <tree-ish> argument can be
	used to specify a specific tree-ish (i.e. commit, tag or tree)
	to update the index for the given paths before updating the
	working tree.</p>
	</div>
	<h2>OPTIONS</h2>
	<div class="sectionbody">
	<dl>
	<dt>
	-q
	</dt>
	<dd>
	<p>
	Quiet, suppress feedback messages.
	</p>
	</dd>
	<dt>
	-f
	</dt>
	<dd>
	<p>
	Proceed even if the index or the working tree differs
	from HEAD. This is used to throw away local changes.
	</p>
	</dd>
	<dt>
	-b
	</dt>
	<dd>
	<p>
	Create a new branch named <new_branch> and start it at
	<branch>. The new branch name must pass all checks defined
	by <a href="git-check-ref-format.html">git-check-ref-format(1)</a>. Some of these checks
	may restrict the characters allowed in a branch name.
	</p>
	</dd>
	<dt>
	--track
	</dt>
	<dd>
	<p>
	When -b is given and a branch is created off a remote branch,
	set up configuration so that git-pull will automatically
	retrieve data from the remote branch. Use this if you always
	pull from the same remote branch into the new branch, or if you
	don't want to use "git pull <repository> <refspec>" explicitly. Set the
	branch.autosetupmerge configuration variable to true if you
	want git-checkout and git-branch to always behave as if
	<em>--track</em> were given.
	</p>
	</dd>
	<dt>
	--no-track
	</dt>
	<dd>
	<p>
	When -b is given and a branch is created off a remote branch,
	set up configuration so that git-pull will not retrieve data
	from the remote branch, ignoring the branch.autosetupmerge
	configuration variable.
	</p>
	</dd>
	<dt>
	-l
	</dt>
	<dd>
	<p>
	Create the new branch's reflog. This activates recording of
	all changes made to the branch ref, enabling use of date
	based sha1 expressions such as "<branchname>@{yesterday}".
	</p>
	</dd>
	<dt>
	-m
	</dt>
	<dd>
	<p>
	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.
	</p>
	<p>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 <tt>git add</tt> (or <tt>git rm</tt> if the merge
	should result in deletion of the path).</p>
	</dd>
	<dt>
	<new_branch>
	</dt>
	<dd>
	<p>
	Name for the new branch.
	</p>
	</dd>
	<dt>
	<branch>
	</dt>
	<dd>
	<p>
	Branch to checkout; may be any object ID that resolves to a
	commit. Defaults to HEAD.
	</p>
	<p>When this parameter names a non-branch (but still a valid commit object),
	your HEAD becomes <em>detached</em>.</p>
	</dd>
	</dl>
	</div>
	<h2>Detached HEAD</h2>
	<div class="sectionbody">
	<p>It is sometimes useful to be able to <em>checkout</em> a commit that is
	not at the tip of one of your branches. The most obvious
	example is to check out the commit at a tagged official release
	point, like this:</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout v2.6.18</tt></pre>
	</div></div>
	<p>Earlier versions of git did not allow this and asked you to
	create a temporary branch using <tt>-b</tt> option, but starting from
	version 1.5.0, the above command <em>detaches</em> your HEAD from the
	current branch and directly point at the commit named by the tag
	(<tt>v2.6.18</tt> in the above example).</p>
	<p>You can use usual git commands while in this state. You can use
	<tt>git-reset --hard $othercommit</tt> to further move around, for
	example. You can make changes and create a new commit on top of
	a detached HEAD. You can even create a merge by using <tt>git
	merge $othercommit</tt>.</p>
	<p>The state you are in while your HEAD is detached is not recorded
	by any branch (which is natural --- you are not on any branch).
	What this means is that you can discard your temporary commits
	and merges by switching back to an existing branch (e.g. <tt>git
	checkout master</tt>), and a later <tt>git prune</tt> or <tt>git gc</tt> would
	garbage-collect them. If you did this by mistake, you can ask
	the reflog for HEAD where you were, e.g.</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git log -g -2 HEAD</tt></pre>
	</div></div>
	</div>
	<h2>EXAMPLES</h2>
	<div class="sectionbody">
	<ol>
	<li>
	<p>
	The following sequence checks out the <tt>master</tt> branch, reverts
	the <tt>Makefile</tt> to two revisions back, deletes hello.c by
	mistake, and gets it back from the index.
	</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout master <b>(1)</b>
	$ git checkout master~2 Makefile <b>(2)</b>
	$ rm -f hello.c
	$ git checkout hello.c <b>(3)</b></tt></pre>
	</div></div>
	<ol>
	<li>
	<p>
	switch branch
	</p>
	</li>
	<li>
	<p>
	take out a file out of other commit
	</p>
	</li>
	<li>
	<p>
	restore hello.c from HEAD of current branch
	</p>
	<p>If you have an unfortunate branch that is named <tt>hello.c</tt>, this
	step would be confused as an instruction to switch to that branch.
	You should instead write:</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout -- hello.c</tt></pre>
	</div></div>
	</li>
	</ol>
	</li>
	<li>
	<p>
	After working in a wrong branch, switching to the correct
	branch would be done using:
	</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout mytopic</tt></pre>
	</div></div>
	<p>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:</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout mytopic
	fatal: Entry 'frotz' not uptodate. Cannot merge.</tt></pre>
	</div></div>
	<p>You can give the <tt>-m</tt> flag to the command, which would try a
	three-way merge:</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout -m mytopic
	Auto-merging frotz</tt></pre>
	</div></div>
	<p>After this three-way merge, the local modifications are _not_
	registered in your index file, so <tt>git diff</tt> would show you what
	changes you made since the tip of the new branch.</p>
	</li>
	<li>
	<p>
	When a merge conflict happens during switching branches with
	the <tt>-m</tt> option, you would see something like this:
	</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ git checkout -m mytopic
	Auto-merging frotz
	merge: warning: conflicts during merge
	ERROR: Merge conflict in frotz
	fatal: merge program failed</tt></pre>
	</div></div>
	<p>At this point, <tt>git diff</tt> 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
	<tt>git add</tt> as usual:</p>
	<div class="listingblock">
	<div class="content">
	<pre><tt>$ edit frotz
	$ git add frotz</tt></pre>
	</div></div>
	</li>
	</ol>
	</div>
	<h2>Author</h2>
	<div class="sectionbody">
	<p>Written by Linus Torvalds <torvalds@osdl.org></p>
	</div>
	<h2>Documentation</h2>
	<div class="sectionbody">
	<p>Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.</p>
	</div>
	<h2>GIT</h2>
	<div class="sectionbody">
	<p>Part of the <a href="git.html">git(7)</a> suite</p>
	</div>
	<div id="footer">
	<div id="footer-text">
	Last updated 07-Jan-2008 07:50:05 UTC
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