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diff --git a/.html/git/theory-and-practice/refs-and-names.html b/.html/git/theory-and-practice/refs-and-names.html deleted file mode 100644 index fdc56a4..0000000 --- a/.html/git/theory-and-practice/refs-and-names.html +++ /dev/null @@ -1,199 +0,0 @@ -<!DOCTYPE html> -<html> -<head> - <title> - The Codex » - Refs and Names - </title> - - <link - rel='stylesheet' - type='text/css' - href='http://fonts.googleapis.com/css?family=Buenard:400,700&subset=latin,latin-ext'> - <link - rel="stylesheet" - type="text/css" - href="../../media/css/reset.css"> - <link - rel="stylesheet" - type="text/css" - href="../../media/css/grimoire.css"> -</head> -<body> - -<div id="shell"> - - <ol id="breadcrumbs"> - - <li class="crumb-0 not-last"> - - <a href="../../">index</a> - - </li> - - <li class="crumb-1 not-last"> - - <a href="../">git</a> - - </li> - - <li class="crumb-2 not-last"> - - <a href="./">theory-and-practice</a> - - </li> - - <li class="crumb-3 last"> - - refs-and-names - - </li> - - </ol> - - - - <div id="article"> - <h1 id="refs-and-names">Refs and Names</h1> -<p>Git's <a href="objects">object system</a> stores most of the data for projects tracked in -Git, but only provides SHA-1 hashes. This is basically useless if you want to -make practical use of Git, so Git also has a naming mechanism called “refs” -that provide human-meaningful names for objects.</p> -<p>There are two kinds of refs:</p> -<ul> -<li> -<p>“Normal” refs, which are names that resolve directly to SHA-1 hashes. These - are the vast majority of refs in most repositories.</p> -</li> -<li> -<p>“Symbolic” refs, which are names that resolve to other refs. In most - repositories, only a few of these appear. (Circular references are possible - with symbolic refs. Git will refuse to resolve these.)</p> -</li> -</ul> -<p>Anywhere you could use a SHA-1, you can use a ref instead. Git interprets them -identically, after resolving the ref down to the SHA-1.</p> -<h2 id="namespaces">Namespaces</h2> -<p>Every operation in Git that uses a name of some sort, including branching -(branch names), tagging (tag names), fetching (remote-tracking branch names), -and pushing (many kinds of name), expands those names to refs, using a -namespace convention. The following namespaces are common:</p> -<ul> -<li> -<p><code>refs/heads/NAME</code>: branches. The branch name is the ref name with - <code>refs/heads/</code> removed. Names generally point to commits.</p> -</li> -<li> -<p><code>refs/remotes/REMOTE/NAME</code>: “remote-tracking” branches. These are maintained - in tandem by <code>git remote</code> and <code>git fetch</code>, to cache the state of other - repositories. Names generally point to commits.</p> -</li> -<li> -<p><code>refs/tags/NAME</code>: tags. The tag name is the ref name with <code>refs/heads/</code> - removed. Names generally point to commits or tag objects.</p> -</li> -<li> -<p><code>refs/bisect/STATE</code>: <code>git bisect</code> markers for known-good and known-bad - revisions, from which the rest of the bisect state can be derived.</p> -</li> -</ul> -<p>There are also a few special refs directly in the <code>refs/</code> namespace, most -notably:</p> -<ul> -<li><code>refs/stash</code>: The most recent stash entry, as maintained by <code>git stash</code>. - (Other stash entries are maintained by a separate system.) Names generally - point to commits.</li> -</ul> -<p>Tools can invent new refs for their own purposes, or manipulate existing refs; -the convention is that tools that use refs (which is, as I said, most of them) -respect the state of the ref as if they'd created that state themselves, -rather than sanity-checking the ref before using it.</p> -<h2 id="special-refs">Special refs</h2> -<p>There are a handful of special refs used by Git commands for their own -operation. These refs do <em>not</em> begin with <code>refs/</code>:</p> -<ul> -<li> -<p><code>HEAD</code>: the “current” commit for most operations. This is set when checking - out a commit, and many revision-related commands default to <code>HEAD</code> if not - given a revision to operate on. <code>HEAD</code> can either be a symbolic ref - (pointing to a branch ref) or a normal ref (pointing directly to a commit), - and is very frequently a symbolic ref.</p> -</li> -<li> -<p><code>MERGE_HEAD</code>: during a merge, <code>MERGE_HEAD</code> resolves to the commit whose - history is being merged.</p> -</li> -<li> -<p><code>ORIG_HEAD</code>: set by operations that change <code>HEAD</code> in potentially destructive - ways by resolving <code>HEAD</code> before making the change.</p> -</li> -<li> -<p><code>CHERRY_PICK_HEAD</code> is set during <code>git cherry-pick</code> to the commit whose - changes are being copied.</p> -</li> -<li> -<p><code>FETCH_HEAD</code> is set by the forms of <code>git fetch</code> that fetch a single ref, and - points to the commit the fetched ref pointed to.</p> -</li> -</ul> -<h2 id="examining-and-manipulating-refs">Examining and manipulating refs</h2> -<p>The <code>git show-ref</code> command will list the refs in namespaces under <code>refs</code> in -your repository, printing the SHA-1 hashes they resolve to. Pass <code>--head</code> to -also include <code>HEAD</code>.</p> -<p>The following commands can be used to manipulate refs directly:</p> -<ul> -<li> -<p><code>git update-ref <ref> <sha1></code> forcibly sets <code><ref></code> to the passed <code><sha1></code>.</p> -</li> -<li> -<p><code>git update-ref -d <ref></code> deletes a ref.</p> -</li> -<li> -<p><code>git symbolic-ref <ref></code> prints the target of <code><ref></code>, if <code><ref></code> is a - symbolic ref. (It will fail with an error message for normal refs.)</p> -</li> -<li> -<p><code>git symbolic-ref <ref> <target></code> forcibly makes <code><ref></code> a symbolic ref - pointing to <code><target></code>.</p> -</li> -</ul> -<p>Additionally, you can see what ref a given name resolves to using <code>git -rev-parse --symbolic-full-name <name></code> or <code>git show-ref <name></code>.</p> - </div> - - - -<div id="comments"> -<div id="disqus_thread"></div> -<script type="text/javascript"> - /* * * CONFIGURATION VARIABLES: EDIT BEFORE PASTING INTO YOUR WEBPAGE * * */ - var disqus_shortname = 'grimoire'; // required: replace example with your forum shortname - - /* * * DON'T EDIT BELOW THIS LINE * * */ - (function() { - var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true; - dsq.src = 'http://' + disqus_shortname + '.disqus.com/embed.js'; - (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq); - })(); -</script> -<noscript>Please enable JavaScript to view the <a href="http://disqus.com/?ref_noscript">comments powered by Disqus.</a></noscript> -<a href="http://disqus.com" class="dsq-brlink">comments powered by <span class="logo-disqus">Disqus</span></a> -</div> - - - - <div id="footer"> - <p> - - The Codex — - - Powered by <a href="http://markdoc.org/">Markdoc</a>. - -<a href="https://bitbucket.org/ojacobson/grimoire.ca/src/master/wiki/git/theory-and-practice/refs-and-names.md">See this page on Bitbucket</a> (<a href="https://bitbucket.org/ojacobson/grimoire.ca/history-node/master/wiki/git/theory-and-practice/refs-and-names.md">history</a>). - - </p> - </div> - -</div> -</body> -</html>
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