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227 div#footer-badges { display: none; }
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229 include::./stylesheets/xhtml11-manpage.css[]
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232 div.sidebar-content {
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254 div.exampleblock-content {
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255 border-left: 2px solid silver;
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256 padding-left: 0.5em;
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259 <title>git(7)</title>
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267 <div class="sectionbody">
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269 the stupid content tracker
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274 <div class="sectionbody">
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275 <p><em>git</em> [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ARGS]</p>
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277 <h2>DESCRIPTION</h2>
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278 <div class="sectionbody">
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279 <p><em>git</em> is both a program and a directory content tracker system.
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280 The program <em>git</em> is just a wrapper to reach the core git programs
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281 (or a potty if you like, as it's not exactly porcelain but still
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282 brings your stuff to the plumbing).</p>
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285 <div class="sectionbody">
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292 Prints the git suite version that the <em>git</em> program came from.
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300 Prints the synopsis and a list of the most commonly used
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301 commands. If a git command is named this option will bring up
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302 the man-page for that command. If the option <em>--all</em> or <em>-a</em> is
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303 given then all available commands are printed.
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311 Path to wherever your core git programs are installed.
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312 This can also be controlled by setting the GIT_EXEC_PATH
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313 environment variable. If no path is given <em>git</em> will print
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314 the current setting and then exit.
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319 <h2>NOT LEARNING CORE GIT COMMANDS</h2>
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320 <div class="sectionbody">
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321 <p>This manual is intended to give complete background information
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322 and internal workings of git, which may be too much for most
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323 people. The <a href="#Discussion">[Discussion]</a> section below contains much useful
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324 definition and clarification - read that first.</p>
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325 <p>If you are interested in using git to manage (version control)
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326 projects, use <a href="tutorial.html">The Tutorial</a> to get you started,
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327 and then <a href="everyday.html">Everyday GIT</a> as a guide to the
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328 minimum set of commands you need to know for day-to-day work.
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329 Most likely, that will get you started, and you can go a long
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330 way without knowing the low level details too much.</p>
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331 <p>The <a href="core-tutorial.html">Core tutorial</a> document covers how things
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332 internally work.</p>
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333 <p>If you are migrating from CVS, <a href="cvs-migration.html">cvs
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334 migration</a> document may be helpful after you finish the
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336 <p>After you get the general feel from the tutorial and this
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337 overview page, you may want to take a look at the
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338 <a href="howto-index.html">howto</a> documents.</p>
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340 <h2>CORE GIT COMMANDS</h2>
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341 <div class="sectionbody">
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342 <p>If you are writing your own Porcelain, you need to be familiar
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343 with most of the low level commands --- I suggest starting from
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344 <a href="git-update-index.html">git-update-index(1)</a> and <a href="git-read-tree.html">git-read-tree(1)</a>.</p>
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346 <h2>Commands Overview</h2>
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347 <div class="sectionbody">
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348 <p>The git commands can helpfully be split into those that manipulate
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349 the repository, the index and the files in the working tree, those that
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350 interrogate and compare them, and those that moves objects and
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351 references between repositories.</p>
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352 <p>In addition, git itself comes with a spartan set of porcelain
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353 commands. They are usable but are not meant to compete with real
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355 <p>There are also some ancillary programs that can be viewed as useful
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356 aids for using the core commands but which are unlikely to be used by
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357 SCMs layered over git.</p>
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358 <h3>Manipulation commands</h3>
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361 <a href="git-apply.html">git-apply(1)</a>
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365 Reads a "diff -up1" or git generated patch file and
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366 applies it to the working tree.
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370 <a href="git-checkout-index.html">git-checkout-index(1)</a>
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374 Copy files from the index to the working tree.
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378 <a href="git-commit-tree.html">git-commit-tree(1)</a>
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382 Creates a new commit object.
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386 <a href="git-hash-object.html">git-hash-object(1)</a>
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390 Computes the object ID from a file.
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394 <a href="git-index-pack.html">git-index-pack(1)</a>
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398 Build pack idx file for an existing packed archive.
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402 <a href="git-init-db.html">git-init-db(1)</a>
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406 Creates an empty git object database, or reinitialize an
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411 <a href="git-merge-index.html">git-merge-index(1)</a>
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415 Runs a merge for files needing merging.
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419 <a href="git-mktag.html">git-mktag(1)</a>
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423 Creates a tag object.
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427 <a href="git-pack-objects.html">git-pack-objects(1)</a>
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431 Creates a packed archive of objects.
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435 <a href="git-prune-packed.html">git-prune-packed(1)</a>
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439 Remove extra objects that are already in pack files.
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443 <a href="git-read-tree.html">git-read-tree(1)</a>
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447 Reads tree information into the index.
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451 <a href="git-repo-config.html">git-repo-config(1)</a>
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455 Get and set options in .git/config.
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459 <a href="git-unpack-objects.html">git-unpack-objects(1)</a>
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463 Unpacks objects out of a packed archive.
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467 <a href="git-update-index.html">git-update-index(1)</a>
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471 Registers files in the working tree to the index.
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475 <a href="git-write-tree.html">git-write-tree(1)</a>
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479 Creates a tree from the index.
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483 <h3>Interrogation commands</h3>
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486 <a href="git-cat-file.html">git-cat-file(1)</a>
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490 Provide content or type/size information for repository objects.
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494 <a href="git-describe.html">git-describe(1)</a>
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498 Show the most recent tag that is reachable from a commit.
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502 <a href="git-diff-index.html">git-diff-index(1)</a>
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506 Compares content and mode of blobs between the index and repository.
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510 <a href="git-diff-files.html">git-diff-files(1)</a>
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514 Compares files in the working tree and the index.
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518 <a href="git-diff-stages.html">git-diff-stages(1)</a>
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522 Compares two "merge stages" in the index.
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526 <a href="git-diff-tree.html">git-diff-tree(1)</a>
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530 Compares the content and mode of blobs found via two tree objects.
\r
534 <a href="git-fsck-objects.html">git-fsck-objects(1)</a>
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538 Verifies the connectivity and validity of the objects in the database.
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542 <a href="git-ls-files.html">git-ls-files(1)</a>
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546 Information about files in the index and the working tree.
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550 <a href="git-ls-tree.html">git-ls-tree(1)</a>
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554 Displays a tree object in human readable form.
\r
558 <a href="git-merge-base.html">git-merge-base(1)</a>
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562 Finds as good common ancestors as possible for a merge.
\r
566 <a href="git-name-rev.html">git-name-rev(1)</a>
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570 Find symbolic names for given revs.
\r
574 <a href="git-pack-redundant.html">git-pack-redundant(1)</a>
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578 Find redundant pack files.
\r
582 <a href="git-rev-list.html">git-rev-list(1)</a>
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586 Lists commit objects in reverse chronological order.
\r
590 <a href="git-show-index.html">git-show-index(1)</a>
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594 Displays contents of a pack idx file.
\r
598 <a href="git-tar-tree.html">git-tar-tree(1)</a>
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602 Creates a tar archive of the files in the named tree object.
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606 <a href="git-unpack-file.html">git-unpack-file(1)</a>
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610 Creates a temporary file with a blob's contents.
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614 <a href="git-var.html">git-var(1)</a>
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618 Displays a git logical variable.
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622 <a href="git-verify-pack.html">git-verify-pack(1)</a>
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626 Validates packed git archive files.
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630 <p>In general, the interrogate commands do not touch the files in
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631 the working tree.</p>
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632 <h3>Synching repositories</h3>
\r
635 <a href="git-clone-pack.html">git-clone-pack(1)</a>
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639 Clones a repository into the current repository (engine
\r
640 for ssh and local transport).
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644 <a href="git-fetch-pack.html">git-fetch-pack(1)</a>
\r
648 Updates from a remote repository (engine for ssh and
\r
653 <a href="git-http-fetch.html">git-http-fetch(1)</a>
\r
657 Downloads a remote git repository via HTTP by walking
\r
662 <a href="git-local-fetch.html">git-local-fetch(1)</a>
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666 Duplicates another git repository on a local system by
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667 walking commit chain.
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671 <a href="git-peek-remote.html">git-peek-remote(1)</a>
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675 Lists references on a remote repository using
\r
676 upload-pack protocol (engine for ssh and local
\r
681 <a href="git-receive-pack.html">git-receive-pack(1)</a>
\r
685 Invoked by <em>git-send-pack</em> to receive what is pushed to it.
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689 <a href="git-send-pack.html">git-send-pack(1)</a>
\r
693 Pushes to a remote repository, intelligently.
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697 <a href="git-http-push.html">git-http-push(1)</a>
\r
701 Push missing objects using HTTP/DAV.
\r
705 <a href="git-shell.html">git-shell(1)</a>
\r
709 Restricted shell for GIT-only SSH access.
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713 <a href="git-ssh-fetch.html">git-ssh-fetch(1)</a>
\r
717 Pulls from a remote repository over ssh connection by
\r
718 walking commit chain.
\r
722 <a href="git-ssh-upload.html">git-ssh-upload(1)</a>
\r
726 Helper "server-side" program used by git-ssh-fetch.
\r
730 <a href="git-update-server-info.html">git-update-server-info(1)</a>
\r
734 Updates auxiliary information on a dumb server to help
\r
735 clients discover references and packs on it.
\r
739 <a href="git-upload-pack.html">git-upload-pack(1)</a>
\r
743 Invoked by <em>git-clone-pack</em> and <em>git-fetch-pack</em> to push
\r
744 what are asked for.
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749 <h2>Porcelain-ish Commands</h2>
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750 <div class="sectionbody">
\r
753 <a href="git-add.html">git-add(1)</a>
\r
757 Add paths to the index.
\r
761 <a href="git-am.html">git-am(1)</a>
\r
765 Apply patches from a mailbox, but cooler.
\r
769 <a href="git-applymbox.html">git-applymbox(1)</a>
\r
773 Apply patches from a mailbox, original version by Linus.
\r
777 <a href="git-bisect.html">git-bisect(1)</a>
\r
781 Find the change that introduced a bug by binary search.
\r
785 <a href="git-branch.html">git-branch(1)</a>
\r
789 Create and Show branches.
\r
793 <a href="git-checkout.html">git-checkout(1)</a>
\r
797 Checkout and switch to a branch.
\r
801 <a href="git-cherry-pick.html">git-cherry-pick(1)</a>
\r
805 Cherry-pick the effect of an existing commit.
\r
809 <a href="git-clone.html">git-clone(1)</a>
\r
813 Clones a repository into a new directory.
\r
817 <a href="git-commit.html">git-commit(1)</a>
\r
821 Record changes to the repository.
\r
825 <a href="git-diff.html">git-diff(1)</a>
\r
829 Show changes between commits, commit and working tree, etc.
\r
833 <a href="git-fetch.html">git-fetch(1)</a>
\r
837 Download from a remote repository via various protocols.
\r
841 <a href="git-format-patch.html">git-format-patch(1)</a>
\r
845 Prepare patches for e-mail submission.
\r
849 <a href="git-grep.html">git-grep(1)</a>
\r
853 Print lines matching a pattern.
\r
857 <a href="git-log.html">git-log(1)</a>
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865 <a href="git-ls-remote.html">git-ls-remote(1)</a>
\r
869 Shows references in a remote or local repository.
\r
873 <a href="git-merge.html">git-merge(1)</a>
\r
877 Grand unified merge driver.
\r
881 <a href="git-mv.html">git-mv(1)</a>
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885 Move or rename a file, a directory, or a symlink.
\r
889 <a href="git-pull.html">git-pull(1)</a>
\r
893 Fetch from and merge with a remote repository.
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897 <a href="git-push.html">git-push(1)</a>
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901 Update remote refs along with associated objects.
\r
905 <a href="git-rebase.html">git-rebase(1)</a>
\r
909 Rebase local commits to the updated upstream head.
\r
913 <a href="git-repack.html">git-repack(1)</a>
\r
917 Pack unpacked objects in a repository.
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921 <a href="git-rerere.html">git-rerere(1)</a>
\r
925 Reuse recorded resolution of conflicted merges.
\r
929 <a href="git-reset.html">git-reset(1)</a>
\r
933 Reset current HEAD to the specified state.
\r
937 <a href="git-resolve.html">git-resolve(1)</a>
\r
945 <a href="git-revert.html">git-revert(1)</a>
\r
949 Revert an existing commit.
\r
953 <a href="git-shortlog.html">git-shortlog(1)</a>
\r
957 Summarizes <em>git log</em> output.
\r
961 <a href="git-show.html">git-show(1)</a>
\r
965 Show one commit log and its diff.
\r
969 <a href="git-show-branch.html">git-show-branch(1)</a>
\r
973 Show branches and their commits.
\r
977 <a href="git-status.html">git-status(1)</a>
\r
981 Shows the working tree status.
\r
985 <a href="git-verify-tag.html">git-verify-tag(1)</a>
\r
989 Check the GPG signature of tag.
\r
993 <a href="git-whatchanged.html">git-whatchanged(1)</a>
\r
997 Shows commit logs and differences they introduce.
\r
1002 <h2>Ancillary Commands</h2>
\r
1003 <div class="sectionbody">
\r
1004 <p>Manipulators:</p>
\r
1007 <a href="git-applypatch.html">git-applypatch(1)</a>
\r
1011 Apply one patch extracted from an e-mail.
\r
1015 <a href="git-archimport.html">git-archimport(1)</a>
\r
1019 Import an arch repository into git.
\r
1023 <a href="git-convert-objects.html">git-convert-objects(1)</a>
\r
1027 Converts old-style git repository.
\r
1031 <a href="git-cvsimport.html">git-cvsimport(1)</a>
\r
1035 Salvage your data out of another SCM people love to hate.
\r
1039 <a href="git-cvsexportcommit.html">git-cvsexportcommit(1)</a>
\r
1043 Export a single commit to a CVS checkout.
\r
1047 <a href="git-lost-found.html">git-lost-found(1)</a>
\r
1051 Recover lost refs that luckily have not yet been pruned.
\r
1055 <a href="git-merge-one-file.html">git-merge-one-file(1)</a>
\r
1059 The standard helper program to use with <tt>git-merge-index</tt>.
\r
1063 <a href="git-prune.html">git-prune(1)</a>
\r
1067 Prunes all unreachable objects from the object database.
\r
1071 <a href="git-relink.html">git-relink(1)</a>
\r
1075 Hardlink common objects in local repositories.
\r
1079 <a href="git-svnimport.html">git-svnimport(1)</a>
\r
1083 Import a SVN repository into git.
\r
1087 <a href="git-sh-setup.html">git-sh-setup(1)</a>
\r
1091 Common git shell script setup code.
\r
1095 <a href="git-symbolic-ref.html">git-symbolic-ref(1)</a>
\r
1099 Read and modify symbolic refs.
\r
1103 <a href="git-tag.html">git-tag(1)</a>
\r
1107 An example script to create a tag object signed with GPG.
\r
1111 <a href="git-update-ref.html">git-update-ref(1)</a>
\r
1115 Update the object name stored in a ref safely.
\r
1119 <p>Interrogators:</p>
\r
1122 <a href="git-check-ref-format.html">git-check-ref-format(1)</a>
\r
1126 Make sure ref name is well formed.
\r
1130 <a href="git-cherry.html">git-cherry(1)</a>
\r
1134 Find commits not merged upstream.
\r
1138 <a href="git-count-objects.html">git-count-objects(1)</a>
\r
1142 Count unpacked number of objects and their disk consumption.
\r
1146 <a href="git-daemon.html">git-daemon(1)</a>
\r
1150 A really simple server for git repositories.
\r
1154 <a href="git-get-tar-commit-id.html">git-get-tar-commit-id(1)</a>
\r
1158 Extract commit ID from an archive created using git-tar-tree.
\r
1162 <a href="git-mailinfo.html">git-mailinfo(1)</a>
\r
1166 Extracts patch and authorship information from a single
\r
1167 e-mail message, optionally transliterating the commit
\r
1168 message into utf-8.
\r
1172 <a href="git-mailsplit.html">git-mailsplit(1)</a>
\r
1176 A stupid program to split UNIX mbox format mailbox into
\r
1177 individual pieces of e-mail.
\r
1181 <a href="git-patch-id.html">git-patch-id(1)</a>
\r
1185 Compute unique ID for a patch.
\r
1189 <a href="git-parse-remote.html">git-parse-remote(1)</a>
\r
1193 Routines to help parsing <tt>$GIT_DIR/remotes/</tt> files.
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1197 <a href="git-request-pull.html">git-request-pull(1)</a>
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1205 <a href="git-rev-parse.html">git-rev-parse(1)</a>
\r
1209 Pick out and massage parameters.
\r
1213 <a href="git-send-email.html">git-send-email(1)</a>
\r
1217 Send patch e-mails out of "format-patch --mbox" output.
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1221 <a href="git-symbolic-ref.html">git-symbolic-ref(1)</a>
\r
1225 Read and modify symbolic refs.
\r
1229 <a href="git-stripspace.html">git-stripspace(1)</a>
\r
1233 Filter out empty lines.
\r
1238 <h2>Commands not yet documented</h2>
\r
1239 <div class="sectionbody">
\r
1242 <a href="gitk.html">gitk(1)</a>
\r
1246 The gitk repository browser.
\r
1251 <h2>Configuration Mechanism</h2>
\r
1252 <div class="sectionbody">
\r
1253 <p>Starting from 0.99.9 (actually mid 0.99.8.GIT), <tt>.git/config</tt> file
\r
1254 is used to hold per-repository configuration options. It is a
\r
1255 simple text file modelled after <tt>.ini</tt> format familiar to some
\r
1256 people. Here is an example:</p>
\r
1257 <div class="listingblock">
\r
1258 <div class="content">
\r
1260 # A '#' or ';' character indicates a comment.
\r
1265 ; Don't trust file modes
\r
1270 name = "Junio C Hamano"
\r
1271 email = "junkio@twinsun.com"
\r
1274 <p>Various commands read from the configuration file and adjust
\r
1275 their operation accordingly.</p>
\r
1277 <h2>Identifier Terminology</h2>
\r
1278 <div class="sectionbody">
\r
1285 Indicates the object name for any type of object.
\r
1293 Indicates a blob object name.
\r
1301 Indicates a tree object name.
\r
1309 Indicates a commit object name.
\r
1317 Indicates a tree, commit or tag object name. A
\r
1318 command that takes a <tree-ish> argument ultimately wants to
\r
1319 operate on a <tree> object but automatically dereferences
\r
1320 <commit> and <tag> objects that point at a <tree>.
\r
1328 Indicates that an object type is required.
\r
1329 Currently one of: <tt>blob</tt>, <tt>tree</tt>, <tt>commit</tt>, or <tt>tag</tt>.
\r
1337 Indicates a filename - almost always relative to the
\r
1338 root of the tree structure <tt>GIT_INDEX_FILE</tt> describes.
\r
1343 <h2>Symbolic Identifiers</h2>
\r
1344 <div class="sectionbody">
\r
1345 <p>Any git command accepting any <object> can also use the following
\r
1346 symbolic notation:</p>
\r
1353 indicates the head of the current branch (i.e. the
\r
1354 contents of <tt>$GIT_DIR/HEAD</tt>).
\r
1362 a valid tag <em>name</em>
\r
1363 (i.e. the contents of <tt>$GIT_DIR/refs/tags/<tag></tt>).
\r
1371 a valid head <em>name</em>
\r
1372 (i.e. the contents of <tt>$GIT_DIR/refs/heads/<head></tt>).
\r
1380 a valid snapshot <em>name</em>
\r
1381 (i.e. the contents of <tt>$GIT_DIR/refs/snap/<snap></tt>).
\r
1386 <h2>File/Directory Structure</h2>
\r
1387 <div class="sectionbody">
\r
1388 <p>Please see <a href="repository-layout.html">repository layout</a> document.</p>
\r
1389 <p>Higher level SCMs may provide and manage additional information in the
\r
1390 <tt>$GIT_DIR</tt>.</p>
\r
1392 <h2>Terminology</h2>
\r
1393 <div class="sectionbody">
\r
1394 <p>Please see <a href="glossary.html">glossary</a> document.</p>
\r
1396 <h2>Environment Variables</h2>
\r
1397 <div class="sectionbody">
\r
1398 <p>Various git commands use the following environment variables:</p>
\r
1399 <h3>The git Repository</h3>
\r
1400 <p>These environment variables apply to <em>all</em> core git commands. Nb: it
\r
1401 is worth noting that they may be used/overridden by SCMS sitting above
\r
1402 git so take care if using Cogito etc.</p>
\r
1405 <em>GIT_INDEX_FILE</em>
\r
1409 This environment allows the specification of an alternate
\r
1410 index file. If not specified, the default of <tt>$GIT_DIR/index</tt>
\r
1415 <em>GIT_OBJECT_DIRECTORY</em>
\r
1419 If the object storage directory is specified via this
\r
1420 environment variable then the sha1 directories are created
\r
1421 underneath - otherwise the default <tt>$GIT_DIR/objects</tt>
\r
1422 directory is used.
\r
1426 <em>GIT_ALTERNATE_OBJECT_DIRECTORIES</em>
\r
1430 Due to the immutable nature of git objects, old objects can be
\r
1431 archived into shared, read-only directories. This variable
\r
1432 specifies a ":" separated list of git object directories which
\r
1433 can be used to search for git objects. New objects will not be
\r
1434 written to these directories.
\r
1442 If the <em>GIT_DIR</em> environment variable is set then it
\r
1443 specifies a path to use instead of the default <tt>.git</tt>
\r
1444 for the base of the repository.
\r
1448 <h3>git Commits</h3>
\r
1451 <em>GIT_AUTHOR_NAME</em>
\r
1454 <em>GIT_AUTHOR_EMAIL</em>
\r
1457 <em>GIT_AUTHOR_DATE</em>
\r
1460 <em>GIT_COMMITTER_NAME</em>
\r
1463 <em>GIT_COMMITTER_EMAIL</em>
\r
1467 see <a href="git-commit-tree.html">git-commit-tree(1)</a>
\r
1471 <h3>git Diffs</h3>
\r
1474 <em>GIT_DIFF_OPTS</em>
\r
1477 <em>GIT_EXTERNAL_DIFF</em>
\r
1481 see the "generating patches" section in :
\r
1482 <a href="git-diff-index.html">git-diff-index(1)</a>;
\r
1483 <a href="git-diff-files.html">git-diff-files(1)</a>;
\r
1484 <a href="git-diff-tree.html">git-diff-tree(1)</a>
\r
1489 <h2>Discussion<a id="Discussion"></a></h2>
\r
1490 <div class="sectionbody">
\r
1491 <p>"git" can mean anything, depending on your mood.</p>
\r
1495 random three-letter combination that is pronounceable, and not
\r
1496 actually used by any common UNIX command. The fact that it is a
\r
1497 mispronunciation of "get" may or may not be relevant.
\r
1502 stupid. contemptible and despicable. simple. Take your pick from the
\r
1503 dictionary of slang.
\r
1508 "global information tracker": you're in a good mood, and it actually
\r
1509 works for you. Angels sing, and a light suddenly fills the room.
\r
1514 "goddamn idiotic truckload of sh*t": when it breaks
\r
1518 <p>This is a stupid (but extremely fast) directory content manager. It
\r
1519 doesn't do a whole lot, but what it <em>does</em> do is track directory
\r
1520 contents efficiently.</p>
\r
1521 <p>There are two object abstractions: the "object database", and the
\r
1522 "current directory cache" aka "index".</p>
\r
1523 <h3>The Object Database</h3>
\r
1524 <p>The object database is literally just a content-addressable collection
\r
1525 of objects. All objects are named by their content, which is
\r
1526 approximated by the SHA1 hash of the object itself. Objects may refer
\r
1527 to other objects (by referencing their SHA1 hash), and so you can
\r
1528 build up a hierarchy of objects.</p>
\r
1529 <p>All objects have a statically determined "type" aka "tag", which is
\r
1530 determined at object creation time, and which identifies the format of
\r
1531 the object (i.e. how it is used, and how it can refer to other
\r
1532 objects). There are currently four different object types: "blob",
\r
1533 "tree", "commit" and "tag".</p>
\r
1534 <p>A "blob" object cannot refer to any other object, and is, like the type
\r
1535 implies, a pure storage object containing some user data. It is used to
\r
1536 actually store the file data, i.e. a blob object is associated with some
\r
1537 particular version of some file.</p>
\r
1538 <p>A "tree" object is an object that ties one or more "blob" objects into a
\r
1539 directory structure. In addition, a tree object can refer to other tree
\r
1540 objects, thus creating a directory hierarchy.</p>
\r
1541 <p>A "commit" object ties such directory hierarchies together into
\r
1542 a DAG of revisions - each "commit" is associated with exactly one tree
\r
1543 (the directory hierarchy at the time of the commit). In addition, a
\r
1544 "commit" refers to one or more "parent" commit objects that describe the
\r
1545 history of how we arrived at that directory hierarchy.</p>
\r
1546 <p>As a special case, a commit object with no parents is called the "root"
\r
1547 object, and is the point of an initial project commit. Each project
\r
1548 must have at least one root, and while you can tie several different
\r
1549 root objects together into one project by creating a commit object which
\r
1550 has two or more separate roots as its ultimate parents, that's probably
\r
1551 just going to confuse people. So aim for the notion of "one root object
\r
1552 per project", even if git itself does not enforce that.</p>
\r
1553 <p>A "tag" object symbolically identifies and can be used to sign other
\r
1554 objects. It contains the identifier and type of another object, a
\r
1555 symbolic name (of course!) and, optionally, a signature.</p>
\r
1556 <p>Regardless of object type, all objects share the following
\r
1557 characteristics: they are all deflated with zlib, and have a header
\r
1558 that not only specifies their type, but also provides size information
\r
1559 about the data in the object. It's worth noting that the SHA1 hash
\r
1560 that is used to name the object is the hash of the original data
\r
1561 plus this header, so <tt>sha1sum</tt> <em>file</em> does not match the object name
\r
1562 for <em>file</em>.
\r
1563 (Historical note: in the dawn of the age of git the hash
\r
1564 was the sha1 of the <em>compressed</em> object.)</p>
\r
1565 <p>As a result, the general consistency of an object can always be tested
\r
1566 independently of the contents or the type of the object: all objects can
\r
1567 be validated by verifying that (a) their hashes match the content of the
\r
1568 file and (b) the object successfully inflates to a stream of bytes that
\r
1569 forms a sequence of <ascii type without space> + <space> + <ascii decimal
\r
1570 size> + <byte\0> + <binary object data>.</p>
\r
1571 <p>The structured objects can further have their structure and
\r
1572 connectivity to other objects verified. This is generally done with
\r
1573 the <tt>git-fsck-objects</tt> program, which generates a full dependency graph
\r
1574 of all objects, and verifies their internal consistency (in addition
\r
1575 to just verifying their superficial consistency through the hash).</p>
\r
1576 <p>The object types in some more detail:</p>
\r
1577 <h3>Blob Object</h3>
\r
1578 <p>A "blob" object is nothing but a binary blob of data, and doesn't
\r
1579 refer to anything else. There is no signature or any other
\r
1580 verification of the data, so while the object is consistent (it <em>is</em>
\r
1581 indexed by its sha1 hash, so the data itself is certainly correct), it
\r
1582 has absolutely no other attributes. No name associations, no
\r
1583 permissions. It is purely a blob of data (i.e. normally "file
\r
1585 <p>In particular, since the blob is entirely defined by its data, if two
\r
1586 files in a directory tree (or in multiple different versions of the
\r
1587 repository) have the same contents, they will share the same blob
\r
1588 object. The object is totally independent of its location in the
\r
1589 directory tree, and renaming a file does not change the object that
\r
1590 file is associated with in any way.</p>
\r
1591 <p>A blob is typically created when <a href="git-update-index.html">git-update-index(1)</a>
\r
1592 is run, and its data can be accessed by <a href="git-cat-file.html">git-cat-file(1)</a>.</p>
\r
1593 <h3>Tree Object</h3>
\r
1594 <p>The next hierarchical object type is the "tree" object. A tree object
\r
1595 is a list of mode/name/blob data, sorted by name. Alternatively, the
\r
1596 mode data may specify a directory mode, in which case instead of
\r
1597 naming a blob, that name is associated with another TREE object.</p>
\r
1598 <p>Like the "blob" object, a tree object is uniquely determined by the
\r
1599 set contents, and so two separate but identical trees will always
\r
1600 share the exact same object. This is true at all levels, i.e. it's
\r
1601 true for a "leaf" tree (which does not refer to any other trees, only
\r
1602 blobs) as well as for a whole subdirectory.</p>
\r
1603 <p>For that reason a "tree" object is just a pure data abstraction: it
\r
1604 has no history, no signatures, no verification of validity, except
\r
1605 that since the contents are again protected by the hash itself, we can
\r
1606 trust that the tree is immutable and its contents never change.</p>
\r
1607 <p>So you can trust the contents of a tree to be valid, the same way you
\r
1608 can trust the contents of a blob, but you don't know where those
\r
1609 contents <em>came</em> from.</p>
\r
1610 <p>Side note on trees: since a "tree" object is a sorted list of
\r
1611 "filename+content", you can create a diff between two trees without
\r
1612 actually having to unpack two trees. Just ignore all common parts,
\r
1613 and your diff will look right. In other words, you can effectively
\r
1614 (and efficiently) tell the difference between any two random trees by
\r
1615 O(n) where "n" is the size of the difference, rather than the size of
\r
1617 <p>Side note 2 on trees: since the name of a "blob" depends entirely and
\r
1618 exclusively on its contents (i.e. there are no names or permissions
\r
1619 involved), you can see trivial renames or permission changes by
\r
1620 noticing that the blob stayed the same. However, renames with data
\r
1621 changes need a smarter "diff" implementation.</p>
\r
1622 <p>A tree is created with <a href="git-write-tree.html">git-write-tree(1)</a> and
\r
1623 its data can be accessed by <a href="git-ls-tree.html">git-ls-tree(1)</a>.
\r
1624 Two trees can be compared with <a href="git-diff-tree.html">git-diff-tree(1)</a>.</p>
\r
1625 <h3>Commit Object</h3>
\r
1626 <p>The "commit" object is an object that introduces the notion of
\r
1627 history into the picture. In contrast to the other objects, it
\r
1628 doesn't just describe the physical state of a tree, it describes how
\r
1629 we got there, and why.</p>
\r
1630 <p>A "commit" is defined by the tree-object that it results in, the
\r
1631 parent commits (zero, one or more) that led up to that point, and a
\r
1632 comment on what happened. Again, a commit is not trusted per se:
\r
1633 the contents are well-defined and "safe" due to the cryptographically
\r
1634 strong signatures at all levels, but there is no reason to believe
\r
1635 that the tree is "good" or that the merge information makes sense.
\r
1636 The parents do not have to actually have any relationship with the
\r
1637 result, for example.</p>
\r
1638 <p>Note on commits: unlike real SCM's, commits do not contain
\r
1639 rename information or file mode change information. All of that is
\r
1640 implicit in the trees involved (the result tree, and the result trees
\r
1641 of the parents), and describing that makes no sense in this idiotic
\r
1643 <p>A commit is created with <a href="git-commit-tree.html">git-commit-tree(1)</a> and
\r
1644 its data can be accessed by <a href="git-cat-file.html">git-cat-file(1)</a>.</p>
\r
1646 <p>An aside on the notion of "trust". Trust is really outside the scope
\r
1647 of "git", but it's worth noting a few things. First off, since
\r
1648 everything is hashed with SHA1, you <em>can</em> trust that an object is
\r
1649 intact and has not been messed with by external sources. So the name
\r
1650 of an object uniquely identifies a known state - just not a state that
\r
1651 you may want to trust.</p>
\r
1652 <p>Furthermore, since the SHA1 signature of a commit refers to the
\r
1653 SHA1 signatures of the tree it is associated with and the signatures
\r
1654 of the parent, a single named commit specifies uniquely a whole set
\r
1655 of history, with full contents. You can't later fake any step of the
\r
1656 way once you have the name of a commit.</p>
\r
1657 <p>So to introduce some real trust in the system, the only thing you need
\r
1658 to do is to digitally sign just <em>one</em> special note, which includes the
\r
1659 name of a top-level commit. Your digital signature shows others
\r
1660 that you trust that commit, and the immutability of the history of
\r
1661 commits tells others that they can trust the whole history.</p>
\r
1662 <p>In other words, you can easily validate a whole archive by just
\r
1663 sending out a single email that tells the people the name (SHA1 hash)
\r
1664 of the top commit, and digitally sign that email using something
\r
1666 <p>To assist in this, git also provides the tag object…</p>
\r
1667 <h3>Tag Object</h3>
\r
1668 <p>Git provides the "tag" object to simplify creating, managing and
\r
1669 exchanging symbolic and signed tokens. The "tag" object at its
\r
1670 simplest simply symbolically identifies another object by containing
\r
1671 the sha1, type and symbolic name.</p>
\r
1672 <p>However it can optionally contain additional signature information
\r
1673 (which git doesn't care about as long as there's less than 8k of
\r
1674 it). This can then be verified externally to git.</p>
\r
1675 <p>Note that despite the tag features, "git" itself only handles content
\r
1676 integrity; the trust framework (and signature provision and
\r
1677 verification) has to come from outside.</p>
\r
1678 <p>A tag is created with <a href="git-mktag.html">git-mktag(1)</a>,
\r
1679 its data can be accessed by <a href="git-cat-file.html">git-cat-file(1)</a>,
\r
1680 and the signature can be verified by
\r
1681 <a href="git-verify-tag.html">git-verify-tag(1)</a>.</p>
\r
1683 <h2>The "index" aka "Current Directory Cache"</h2>
\r
1684 <div class="sectionbody">
\r
1685 <p>The index is a simple binary file, which contains an efficient
\r
1686 representation of a virtual directory content at some random time. It
\r
1687 does so by a simple array that associates a set of names, dates,
\r
1688 permissions and content (aka "blob") objects together. The cache is
\r
1689 always kept ordered by name, and names are unique (with a few very
\r
1690 specific rules) at any point in time, but the cache has no long-term
\r
1691 meaning, and can be partially updated at any time.</p>
\r
1692 <p>In particular, the index certainly does not need to be consistent with
\r
1693 the current directory contents (in fact, most operations will depend on
\r
1694 different ways to make the index <em>not</em> be consistent with the directory
\r
1695 hierarchy), but it has three very important attributes:</p>
\r
1696 <p><em>(a) it can re-generate the full state it caches (not just the
\r
1697 directory structure: it contains pointers to the "blob" objects so
\r
1698 that it can regenerate the data too)</em></p>
\r
1699 <p>As a special case, there is a clear and unambiguous one-way mapping
\r
1700 from a current directory cache to a "tree object", which can be
\r
1701 efficiently created from just the current directory cache without
\r
1702 actually looking at any other data. So a directory cache at any one
\r
1703 time uniquely specifies one and only one "tree" object (but has
\r
1704 additional data to make it easy to match up that tree object with what
\r
1705 has happened in the directory)</p>
\r
1706 <p><em>(b) it has efficient methods for finding inconsistencies between that
\r
1707 cached state ("tree object waiting to be instantiated") and the
\r
1708 current state.</em></p>
\r
1709 <p><em>(c) it can additionally efficiently represent information about merge
\r
1710 conflicts between different tree objects, allowing each pathname to be
\r
1711 associated with sufficient information about the trees involved that
\r
1712 you can create a three-way merge between them.</em></p>
\r
1713 <p>Those are the three ONLY things that the directory cache does. It's a
\r
1714 cache, and the normal operation is to re-generate it completely from a
\r
1715 known tree object, or update/compare it with a live tree that is being
\r
1716 developed. If you blow the directory cache away entirely, you generally
\r
1717 haven't lost any information as long as you have the name of the tree
\r
1718 that it described.</p>
\r
1719 <p>At the same time, the index is at the same time also the
\r
1720 staging area for creating new trees, and creating a new tree always
\r
1721 involves a controlled modification of the index file. In particular,
\r
1722 the index file can have the representation of an intermediate tree that
\r
1723 has not yet been instantiated. So the index can be thought of as a
\r
1724 write-back cache, which can contain dirty information that has not yet
\r
1725 been written back to the backing store.</p>
\r
1727 <h2>The Workflow</h2>
\r
1728 <div class="sectionbody">
\r
1729 <p>Generally, all "git" operations work on the index file. Some operations
\r
1730 work <strong>purely</strong> on the index file (showing the current state of the
\r
1731 index), but most operations move data to and from the index file. Either
\r
1732 from the database or from the working directory. Thus there are four
\r
1733 main combinations:</p>
\r
1734 <h3>1) working directory -> index</h3>
\r
1735 <p>You update the index with information from the working directory with
\r
1736 the <a href="git-update-index.html">git-update-index(1)</a> command. You
\r
1737 generally update the index information by just specifying the filename
\r
1738 you want to update, like so:</p>
\r
1739 <div class="literalblock">
\r
1740 <div class="content">
\r
1741 <pre><tt>git-update-index filename</tt></pre>
\r
1743 <p>but to avoid common mistakes with filename globbing etc, the command
\r
1744 will not normally add totally new entries or remove old entries,
\r
1745 i.e. it will normally just update existing cache entries.</p>
\r
1746 <p>To tell git that yes, you really do realize that certain files no
\r
1747 longer exist, or that new files should be added, you
\r
1748 should use the <tt>--remove</tt> and <tt>--add</tt> flags respectively.</p>
\r
1749 <p>NOTE! A <tt>--remove</tt> flag does <em>not</em> mean that subsequent filenames will
\r
1750 necessarily be removed: if the files still exist in your directory
\r
1751 structure, the index will be updated with their new status, not
\r
1752 removed. The only thing <tt>--remove</tt> means is that update-cache will be
\r
1753 considering a removed file to be a valid thing, and if the file really
\r
1754 does not exist any more, it will update the index accordingly.</p>
\r
1755 <p>As a special case, you can also do <tt>git-update-index --refresh</tt>, which
\r
1756 will refresh the "stat" information of each index to match the current
\r
1757 stat information. It will <em>not</em> update the object status itself, and
\r
1758 it will only update the fields that are used to quickly test whether
\r
1759 an object still matches its old backing store object.</p>
\r
1760 <h3>2) index -> object database</h3>
\r
1761 <p>You write your current index file to a "tree" object with the program</p>
\r
1762 <div class="literalblock">
\r
1763 <div class="content">
\r
1764 <pre><tt>git-write-tree</tt></pre>
\r
1766 <p>that doesn't come with any options - it will just write out the
\r
1767 current index into the set of tree objects that describe that state,
\r
1768 and it will return the name of the resulting top-level tree. You can
\r
1769 use that tree to re-generate the index at any time by going in the
\r
1770 other direction:</p>
\r
1771 <h3>3) object database -> index</h3>
\r
1772 <p>You read a "tree" file from the object database, and use that to
\r
1773 populate (and overwrite - don't do this if your index contains any
\r
1774 unsaved state that you might want to restore later!) your current
\r
1775 index. Normal operation is just</p>
\r
1776 <div class="literalblock">
\r
1777 <div class="content">
\r
1778 <pre><tt>git-read-tree <sha1 of tree></tt></pre>
\r
1780 <p>and your index file will now be equivalent to the tree that you saved
\r
1781 earlier. However, that is only your <em>index</em> file: your working
\r
1782 directory contents have not been modified.</p>
\r
1783 <h3>4) index -> working directory</h3>
\r
1784 <p>You update your working directory from the index by "checking out"
\r
1785 files. This is not a very common operation, since normally you'd just
\r
1786 keep your files updated, and rather than write to your working
\r
1787 directory, you'd tell the index files about the changes in your
\r
1788 working directory (i.e. <tt>git-update-index</tt>).</p>
\r
1789 <p>However, if you decide to jump to a new version, or check out somebody
\r
1790 else's version, or just restore a previous tree, you'd populate your
\r
1791 index file with read-tree, and then you need to check out the result
\r
1793 <div class="literalblock">
\r
1794 <div class="content">
\r
1795 <pre><tt>git-checkout-index filename</tt></pre>
\r
1797 <p>or, if you want to check out all of the index, use <tt>-a</tt>.</p>
\r
1798 <p>NOTE! git-checkout-index normally refuses to overwrite old files, so
\r
1799 if you have an old version of the tree already checked out, you will
\r
1800 need to use the "-f" flag (<em>before</em> the "-a" flag or the filename) to
\r
1801 <em>force</em> the checkout.</p>
\r
1802 <p>Finally, there are a few odds and ends which are not purely moving
\r
1803 from one representation to the other:</p>
\r
1804 <h3>5) Tying it all together</h3>
\r
1805 <p>To commit a tree you have instantiated with "git-write-tree", you'd
\r
1806 create a "commit" object that refers to that tree and the history
\r
1807 behind it - most notably the "parent" commits that preceded it in
\r
1809 <p>Normally a "commit" has one parent: the previous state of the tree
\r
1810 before a certain change was made. However, sometimes it can have two
\r
1811 or more parent commits, in which case we call it a "merge", due to the
\r
1812 fact that such a commit brings together ("merges") two or more
\r
1813 previous states represented by other commits.</p>
\r
1814 <p>In other words, while a "tree" represents a particular directory state
\r
1815 of a working directory, a "commit" represents that state in "time",
\r
1816 and explains how we got there.</p>
\r
1817 <p>You create a commit object by giving it the tree that describes the
\r
1818 state at the time of the commit, and a list of parents:</p>
\r
1819 <div class="literalblock">
\r
1820 <div class="content">
\r
1821 <pre><tt>git-commit-tree <tree> -p <parent> [-p <parent2> ..]</tt></pre>
\r
1823 <p>and then giving the reason for the commit on stdin (either through
\r
1824 redirection from a pipe or file, or by just typing it at the tty).</p>
\r
1825 <p>git-commit-tree will return the name of the object that represents
\r
1826 that commit, and you should save it away for later use. Normally,
\r
1827 you'd commit a new <tt>HEAD</tt> state, and while git doesn't care where you
\r
1828 save the note about that state, in practice we tend to just write the
\r
1829 result to the file pointed at by <tt>.git/HEAD</tt>, so that we can always see
\r
1830 what the last committed state was.</p>
\r
1831 <p>Here is an ASCII art by Jon Loeliger that illustrates how
\r
1832 various pieces fit together.</p>
\r
1833 <div class="listingblock">
\r
1834 <div class="content">
\r
1860 checkout-index -u | | checkout-index
\r
1869 <h3>6) Examining the data</h3>
\r
1870 <p>You can examine the data represented in the object database and the
\r
1871 index with various helper tools. For every object, you can use
\r
1872 <a href="git-cat-file.html">git-cat-file(1)</a> to examine details about the
\r
1874 <div class="literalblock">
\r
1875 <div class="content">
\r
1876 <pre><tt>git-cat-file -t <objectname></tt></pre>
\r
1878 <p>shows the type of the object, and once you have the type (which is
\r
1879 usually implicit in where you find the object), you can use</p>
\r
1880 <div class="literalblock">
\r
1881 <div class="content">
\r
1882 <pre><tt>git-cat-file blob|tree|commit|tag <objectname></tt></pre>
\r
1884 <p>to show its contents. NOTE! Trees have binary content, and as a result
\r
1885 there is a special helper for showing that content, called
\r
1886 <tt>git-ls-tree</tt>, which turns the binary content into a more easily
\r
1887 readable form.</p>
\r
1888 <p>It's especially instructive to look at "commit" objects, since those
\r
1889 tend to be small and fairly self-explanatory. In particular, if you
\r
1890 follow the convention of having the top commit name in <tt>.git/HEAD</tt>,
\r
1892 <div class="literalblock">
\r
1893 <div class="content">
\r
1894 <pre><tt>git-cat-file commit HEAD</tt></pre>
\r
1896 <p>to see what the top commit was.</p>
\r
1897 <h3>7) Merging multiple trees</h3>
\r
1898 <p>Git helps you do a three-way merge, which you can expand to n-way by
\r
1899 repeating the merge procedure arbitrary times until you finally
\r
1900 "commit" the state. The normal situation is that you'd only do one
\r
1901 three-way merge (two parents), and commit it, but if you like to, you
\r
1902 can do multiple parents in one go.</p>
\r
1903 <p>To do a three-way merge, you need the two sets of "commit" objects
\r
1904 that you want to merge, use those to find the closest common parent (a
\r
1905 third "commit" object), and then use those commit objects to find the
\r
1906 state of the directory ("tree" object) at these points.</p>
\r
1907 <p>To get the "base" for the merge, you first look up the common parent
\r
1908 of two commits with</p>
\r
1909 <div class="literalblock">
\r
1910 <div class="content">
\r
1911 <pre><tt>git-merge-base <commit1> <commit2></tt></pre>
\r
1913 <p>which will return you the commit they are both based on. You should
\r
1914 now look up the "tree" objects of those commits, which you can easily
\r
1915 do with (for example)</p>
\r
1916 <div class="literalblock">
\r
1917 <div class="content">
\r
1918 <pre><tt>git-cat-file commit <commitname> | head -1</tt></pre>
\r
1920 <p>since the tree object information is always the first line in a commit
\r
1922 <p>Once you know the three trees you are going to merge (the one
\r
1923 "original" tree, aka the common case, and the two "result" trees, aka
\r
1924 the branches you want to merge), you do a "merge" read into the
\r
1925 index. This will complain if it has to throw away your old index contents, so you should
\r
1926 make sure that you've committed those - in fact you would normally
\r
1927 always do a merge against your last commit (which should thus match
\r
1928 what you have in your current index anyway).</p>
\r
1929 <p>To do the merge, do</p>
\r
1930 <div class="literalblock">
\r
1931 <div class="content">
\r
1932 <pre><tt>git-read-tree -m -u <origtree> <yourtree> <targettree></tt></pre>
\r
1934 <p>which will do all trivial merge operations for you directly in the
\r
1935 index file, and you can just write the result out with
\r
1936 <tt>git-write-tree</tt>.</p>
\r
1937 <p>Historical note. We did not have <tt>-u</tt> facility when this
\r
1938 section was first written, so we used to warn that
\r
1939 the merge is done in the index file, not in your
\r
1940 working tree, and your working tree will not match your
\r
1941 index after this step.
\r
1942 This is no longer true. The above command, thanks to <tt>-u</tt>
\r
1943 option, updates your working tree with the merge results for
\r
1944 paths that have been trivially merged.</p>
\r
1945 <h3>8) Merging multiple trees, continued</h3>
\r
1946 <p>Sadly, many merges aren't trivial. If there are files that have
\r
1947 been added.moved or removed, or if both branches have modified the
\r
1948 same file, you will be left with an index tree that contains "merge
\r
1949 entries" in it. Such an index tree can <em>NOT</em> be written out to a tree
\r
1950 object, and you will have to resolve any such merge clashes using
\r
1951 other tools before you can write out the result.</p>
\r
1952 <p>You can examine such index state with <tt>git-ls-files --unmerged</tt>
\r
1953 command. An example:</p>
\r
1954 <div class="listingblock">
\r
1955 <div class="content">
\r
1956 <pre><tt>$ git-read-tree -m $orig HEAD $target
\r
1957 $ git-ls-files --unmerged
\r
1958 100644 263414f423d0e4d70dae8fe53fa34614ff3e2860 1 hello.c
\r
1959 100644 06fa6a24256dc7e560efa5687fa84b51f0263c3a 2 hello.c
\r
1960 100644 cc44c73eb783565da5831b4d820c962954019b69 3 hello.c</tt></pre>
\r
1962 <p>Each line of the <tt>git-ls-files --unmerged</tt> output begins with
\r
1963 the blob mode bits, blob SHA1, <em>stage number</em>, and the
\r
1964 filename. The <em>stage number</em> is git's way to say which tree it
\r
1965 came from: stage 1 corresponds to <tt>$orig</tt> tree, stage 2 <tt>HEAD</tt>
\r
1966 tree, and stage3 <tt>$target</tt> tree.</p>
\r
1967 <p>Earlier we said that trivial merges are done inside
\r
1968 <tt>git-read-tree -m</tt>. For example, if the file did not change
\r
1969 from <tt>$orig</tt> to <tt>HEAD</tt> nor <tt>$target</tt>, or if the file changed
\r
1970 from <tt>$orig</tt> to <tt>HEAD</tt> and <tt>$orig</tt> to <tt>$target</tt> the same way,
\r
1971 obviously the final outcome is what is in <tt>HEAD</tt>. What the
\r
1972 above example shows is that file <tt>hello.c</tt> was changed from
\r
1973 <tt>$orig</tt> to <tt>HEAD</tt> and <tt>$orig</tt> to <tt>$target</tt> in a different way.
\r
1974 You could resolve this by running your favorite 3-way merge
\r
1975 program, e.g. <tt>diff3</tt> or <tt>merge</tt>, on the blob objects from
\r
1976 these three stages yourself, like this:</p>
\r
1977 <div class="listingblock">
\r
1978 <div class="content">
\r
1979 <pre><tt>$ git-cat-file blob 263414f... >hello.c~1
\r
1980 $ git-cat-file blob 06fa6a2... >hello.c~2
\r
1981 $ git-cat-file blob cc44c73... >hello.c~3
\r
1982 $ merge hello.c~2 hello.c~1 hello.c~3</tt></pre>
\r
1984 <p>This would leave the merge result in <tt>hello.c~2</tt> file, along
\r
1985 with conflict markers if there are conflicts. After verifying
\r
1986 the merge result makes sense, you can tell git what the final
\r
1987 merge result for this file is by:</p>
\r
1988 <div class="literalblock">
\r
1989 <div class="content">
\r
1990 <pre><tt>mv -f hello.c~2 hello.c
\r
1991 git-update-index hello.c</tt></pre>
\r
1993 <p>When a path is in unmerged state, running <tt>git-update-index</tt> for
\r
1994 that path tells git to mark the path resolved.</p>
\r
1995 <p>The above is the description of a git merge at the lowest level,
\r
1996 to help you understand what conceptually happens under the hood.
\r
1997 In practice, nobody, not even git itself, uses three <tt>git-cat-file</tt>
\r
1998 for this. There is <tt>git-merge-index</tt> program that extracts the
\r
1999 stages to temporary files and calls a "merge" script on it:</p>
\r
2000 <div class="literalblock">
\r
2001 <div class="content">
\r
2002 <pre><tt>git-merge-index git-merge-one-file hello.c</tt></pre>
\r
2004 <p>and that is what higher level <tt>git resolve</tt> is implemented with.</p>
\r
2007 <div class="sectionbody">
\r
2011 git's founding father is Linus Torvalds <torvalds@osdl.org>.
\r
2016 The current git nurse is Junio C Hamano <junkio@cox.net>.
\r
2021 The git potty was written by Andres Ericsson <ae@op5.se>.
\r
2026 General upbringing is handled by the git-list <git@vger.kernel.org>.
\r
2031 <h2>Documentation</h2>
\r
2032 <div class="sectionbody">
\r
2033 <p>The documentation for git suite was started by David Greaves
\r
2034 <david@dgreaves.com>, and later enhanced greatly by the
\r
2035 contributors on the git-list <git@vger.kernel.org>.</p>
\r
2038 <div class="sectionbody">
\r
2039 <p>Part of the <a href="git.html">git(7)</a> suite</p>
\r
2042 <div id="footer-text">
\r
2043 Last updated 18-Mar-2006 07:45:36 UTC
\r
projects / git.git / blob