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227 div#footer-badges { display: none; }
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229 include::./stylesheets/xhtml11-manpage.css[]
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230 /* Workarounds for IE6's broken and incomplete CSS2. */
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232 div.sidebar-content {
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233 background: #ffffee;
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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 available commands.
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301 If a git command is named this option will bring up the
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302 man-page for that command.
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310 path to wherever your core git programs are installed.
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311 This can also be controlled by setting the GIT_EXEC_PATH
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312 environment variable. If no path is given <em>git</em> will print
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313 the current setting and then exit.
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318 <h2>NOT LEARNING CORE GIT COMMANDS</h2>
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319 <div class="sectionbody">
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320 <p>This manual is intended to give complete background information
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321 and internal workings of git, which may be too much for most
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322 people. The <a href="#Discussion">[Discussion]</a> section below contains much useful
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323 definition and clarification - read that first.</p>
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324 <p>If you are interested in using git to manage (version control)
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325 projects, use <a href="tutorial.html">The Tutorial</a> to get you started,
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326 and then <a href="everyday.html">Everyday GIT</a> as a guide to the
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327 minimum set of commands you need to know for day-to-day work.
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328 Most likely, that will get you started, and you can go a long
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329 way without knowing the low level details too much.</p>
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330 <p>The <a href="core-tutorial.html">Core tutorial</a> document covers how things
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331 internally work.</p>
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332 <p>If you are migrating from CVS, <a href="cvs-migration.html">cvs
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333 migration</a> document may be helpful after you finish the
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335 <p>After you get the general feel from the tutorial and this
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336 overview page, you may want to take a look at the
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337 <a href="howto-index.html">howto</a> documents.</p>
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339 <h2>CORE GIT COMMANDS</h2>
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340 <div class="sectionbody">
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341 <p>If you are writing your own Porcelain, you need to be familiar
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342 with most of the low level commands --- I suggest starting from
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343 <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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345 <h2>Commands Overview</h2>
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346 <div class="sectionbody">
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347 <p>The git commands can helpfully be split into those that manipulate
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348 the repository, the index and the files in the working tree, those that
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349 interrogate and compare them, and those that moves objects and
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350 references between repositories.</p>
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351 <p>In addition, git itself comes with a spartan set of porcelain
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352 commands. They are usable but are not meant to compete with real
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354 <p>There are also some ancillary programs that can be viewed as useful
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355 aids for using the core commands but which are unlikely to be used by
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356 SCMs layered over git.</p>
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357 <h3>Manipulation commands</h3>
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360 <a href="git-apply.html">git-apply(1)</a>
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364 Reads a "diff -up1" or git generated patch file and
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365 applies it to the working tree.
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369 <a href="git-checkout-index.html">git-checkout-index(1)</a>
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373 Copy files from the index to the working tree.
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377 <a href="git-commit-tree.html">git-commit-tree(1)</a>
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381 Creates a new commit object.
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385 <a href="git-hash-object.html">git-hash-object(1)</a>
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389 Computes the object ID from a file.
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393 <a href="git-index-pack.html">git-index-pack(1)</a>
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397 Build pack idx file for an existing packed archive.
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401 <a href="git-init-db.html">git-init-db(1)</a>
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405 Creates an empty git object database, or reinitialize an
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410 <a href="git-merge-index.html">git-merge-index(1)</a>
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414 Runs a merge for files needing merging.
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418 <a href="git-mktag.html">git-mktag(1)</a>
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422 Creates a tag object.
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426 <a href="git-pack-objects.html">git-pack-objects(1)</a>
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430 Creates a packed archive of objects.
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434 <a href="git-prune-packed.html">git-prune-packed(1)</a>
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438 Remove extra objects that are already in pack files.
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442 <a href="git-read-tree.html">git-read-tree(1)</a>
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446 Reads tree information into the index.
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450 <a href="git-repo-config.html">git-repo-config(1)</a>
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454 Get and set options in .git/config.
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458 <a href="git-unpack-objects.html">git-unpack-objects(1)</a>
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462 Unpacks objects out of a packed archive.
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466 <a href="git-update-index.html">git-update-index(1)</a>
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470 Registers files in the working tree to the index.
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474 <a href="git-write-tree.html">git-write-tree(1)</a>
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478 Creates a tree from the index.
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482 <h3>Interrogation commands</h3>
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485 <a href="git-cat-file.html">git-cat-file(1)</a>
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489 Provide content or type/size information for repository objects.
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493 <a href="git-describe.html">git-describe(1)</a>
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497 Show the most recent tag that is reachable from a commit.
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501 <a href="git-diff-index.html">git-diff-index(1)</a>
\r
505 Compares content and mode of blobs between the index and repository.
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509 <a href="git-diff-files.html">git-diff-files(1)</a>
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513 Compares files in the working tree and the index.
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517 <a href="git-diff-stages.html">git-diff-stages(1)</a>
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521 Compares two "merge stages" in the index.
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525 <a href="git-diff-tree.html">git-diff-tree(1)</a>
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529 Compares the content and mode of blobs found via two tree objects.
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533 <a href="git-fsck-objects.html">git-fsck-objects(1)</a>
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537 Verifies the connectivity and validity of the objects in the database.
\r
541 <a href="git-ls-files.html">git-ls-files(1)</a>
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545 Information about files in the index and the working tree.
\r
549 <a href="git-ls-tree.html">git-ls-tree(1)</a>
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553 Displays a tree object in human readable form.
\r
557 <a href="git-merge-base.html">git-merge-base(1)</a>
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561 Finds as good common ancestors as possible for a merge.
\r
565 <a href="git-name-rev.html">git-name-rev(1)</a>
\r
569 Find symbolic names for given revs.
\r
573 <a href="git-pack-redundant.html">git-pack-redundant(1)</a>
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577 Find redundant pack files.
\r
581 <a href="git-rev-list.html">git-rev-list(1)</a>
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585 Lists commit objects in reverse chronological order.
\r
589 <a href="git-show-index.html">git-show-index(1)</a>
\r
593 Displays contents of a pack idx file.
\r
597 <a href="git-tar-tree.html">git-tar-tree(1)</a>
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601 Creates a tar archive of the files in the named tree object.
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605 <a href="git-unpack-file.html">git-unpack-file(1)</a>
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609 Creates a temporary file with a blob's contents.
\r
613 <a href="git-var.html">git-var(1)</a>
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617 Displays a git logical variable.
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621 <a href="git-verify-pack.html">git-verify-pack(1)</a>
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625 Validates packed git archive files.
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629 <p>In general, the interrogate commands do not touch the files in
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630 the working tree.</p>
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631 <h3>Synching repositories</h3>
\r
634 <a href="git-clone-pack.html">git-clone-pack(1)</a>
\r
638 Clones a repository into the current repository (engine
\r
639 for ssh and local transport).
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643 <a href="git-fetch-pack.html">git-fetch-pack(1)</a>
\r
647 Updates from a remote repository (engine for ssh and
\r
652 <a href="git-http-fetch.html">git-http-fetch(1)</a>
\r
656 Downloads a remote git repository via HTTP by walking
\r
661 <a href="git-local-fetch.html">git-local-fetch(1)</a>
\r
665 Duplicates another git repository on a local system by
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666 walking commit chain.
\r
670 <a href="git-peek-remote.html">git-peek-remote(1)</a>
\r
674 Lists references on a remote repository using
\r
675 upload-pack protocol (engine for ssh and local
\r
680 <a href="git-receive-pack.html">git-receive-pack(1)</a>
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684 Invoked by <em>git-send-pack</em> to receive what is pushed to it.
\r
688 <a href="git-send-pack.html">git-send-pack(1)</a>
\r
692 Pushes to a remote repository, intelligently.
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696 <a href="git-http-push.html">git-http-push(1)</a>
\r
700 Push missing objects using HTTP/DAV.
\r
704 <a href="git-shell.html">git-shell(1)</a>
\r
708 Restricted shell for GIT-only SSH access.
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712 <a href="git-ssh-fetch.html">git-ssh-fetch(1)</a>
\r
716 Pulls from a remote repository over ssh connection by
\r
717 walking commit chain.
\r
721 <a href="git-ssh-upload.html">git-ssh-upload(1)</a>
\r
725 Helper "server-side" program used by git-ssh-fetch.
\r
729 <a href="git-update-server-info.html">git-update-server-info(1)</a>
\r
733 Updates auxiliary information on a dumb server to help
\r
734 clients discover references and packs on it.
\r
738 <a href="git-upload-pack.html">git-upload-pack(1)</a>
\r
742 Invoked by <em>git-clone-pack</em> and <em>git-fetch-pack</em> to push
\r
743 what are asked for.
\r
748 <h2>Porcelain-ish Commands</h2>
\r
749 <div class="sectionbody">
\r
752 <a href="git-add.html">git-add(1)</a>
\r
756 Add paths to the index.
\r
760 <a href="git-am.html">git-am(1)</a>
\r
764 Apply patches from a mailbox, but cooler.
\r
768 <a href="git-applymbox.html">git-applymbox(1)</a>
\r
772 Apply patches from a mailbox, original version by Linus.
\r
776 <a href="git-bisect.html">git-bisect(1)</a>
\r
780 Find the change that introduced a bug by binary search.
\r
784 <a href="git-branch.html">git-branch(1)</a>
\r
788 Create and Show branches.
\r
792 <a href="git-checkout.html">git-checkout(1)</a>
\r
796 Checkout and switch to a branch.
\r
800 <a href="git-cherry-pick.html">git-cherry-pick(1)</a>
\r
804 Cherry-pick the effect of an existing commit.
\r
808 <a href="git-clone.html">git-clone(1)</a>
\r
812 Clones a repository into a new directory.
\r
816 <a href="git-commit.html">git-commit(1)</a>
\r
820 Record changes to the repository.
\r
824 <a href="git-diff.html">git-diff(1)</a>
\r
828 Show changes between commits, commit and working tree, etc.
\r
832 <a href="git-fetch.html">git-fetch(1)</a>
\r
836 Download from a remote repository via various protocols.
\r
840 <a href="git-format-patch.html">git-format-patch(1)</a>
\r
844 Prepare patches for e-mail submission.
\r
848 <a href="git-grep.html">git-grep(1)</a>
\r
852 Print lines matching a pattern.
\r
856 <a href="git-log.html">git-log(1)</a>
\r
864 <a href="git-ls-remote.html">git-ls-remote(1)</a>
\r
868 Shows references in a remote or local repository.
\r
872 <a href="git-merge.html">git-merge(1)</a>
\r
876 Grand unified merge driver.
\r
880 <a href="git-mv.html">git-mv(1)</a>
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884 Move or rename a file, a directory, or a symlink.
\r
888 <a href="git-pull.html">git-pull(1)</a>
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892 Fetch from and merge with a remote repository.
\r
896 <a href="git-push.html">git-push(1)</a>
\r
900 Update remote refs along with associated objects.
\r
904 <a href="git-rebase.html">git-rebase(1)</a>
\r
908 Rebase local commits to the updated upstream head.
\r
912 <a href="git-repack.html">git-repack(1)</a>
\r
916 Pack unpacked objects in a repository.
\r
920 <a href="git-rerere.html">git-rerere(1)</a>
\r
924 Reuse recorded resolution of conflicted merges.
\r
928 <a href="git-reset.html">git-reset(1)</a>
\r
932 Reset current HEAD to the specified state.
\r
936 <a href="git-resolve.html">git-resolve(1)</a>
\r
944 <a href="git-revert.html">git-revert(1)</a>
\r
948 Revert an existing commit.
\r
952 <a href="git-shortlog.html">git-shortlog(1)</a>
\r
956 Summarizes <em>git log</em> output.
\r
960 <a href="git-show-branch.html">git-show-branch(1)</a>
\r
964 Show branches and their commits.
\r
968 <a href="git-status.html">git-status(1)</a>
\r
972 Shows the working tree status.
\r
976 <a href="git-verify-tag.html">git-verify-tag(1)</a>
\r
980 Check the GPG signature of tag.
\r
984 <a href="git-whatchanged.html">git-whatchanged(1)</a>
\r
988 Shows commit logs and differences they introduce.
\r
993 <h2>Ancillary Commands</h2>
\r
994 <div class="sectionbody">
\r
995 <p>Manipulators:</p>
\r
998 <a href="git-applypatch.html">git-applypatch(1)</a>
\r
1002 Apply one patch extracted from an e-mail.
\r
1006 <a href="git-archimport.html">git-archimport(1)</a>
\r
1010 Import an arch repository into git.
\r
1014 <a href="git-convert-objects.html">git-convert-objects(1)</a>
\r
1018 Converts old-style git repository.
\r
1022 <a href="git-cvsimport.html">git-cvsimport(1)</a>
\r
1026 Salvage your data out of another SCM people love to hate.
\r
1030 <a href="git-cvsexportcommit.html">git-cvsexportcommit(1)</a>
\r
1034 Export a single commit to a CVS checkout.
\r
1038 <a href="git-lost-found.html">git-lost-found(1)</a>
\r
1042 Recover lost refs that luckily have not yet been pruned.
\r
1046 <a href="git-merge-one-file.html">git-merge-one-file(1)</a>
\r
1050 The standard helper program to use with <tt>git-merge-index</tt>.
\r
1054 <a href="git-prune.html">git-prune(1)</a>
\r
1058 Prunes all unreachable objects from the object database.
\r
1062 <a href="git-relink.html">git-relink(1)</a>
\r
1066 Hardlink common objects in local repositories.
\r
1070 <a href="git-svnimport.html">git-svnimport(1)</a>
\r
1074 Import a SVN repository into git.
\r
1078 <a href="git-sh-setup.html">git-sh-setup(1)</a>
\r
1082 Common git shell script setup code.
\r
1086 <a href="git-symbolic-ref.html">git-symbolic-ref(1)</a>
\r
1090 Read and modify symbolic refs.
\r
1094 <a href="git-tag.html">git-tag(1)</a>
\r
1098 An example script to create a tag object signed with GPG.
\r
1102 <a href="git-update-ref.html">git-update-ref(1)</a>
\r
1106 Update the object name stored in a ref safely.
\r
1110 <p>Interrogators:</p>
\r
1113 <a href="git-check-ref-format.html">git-check-ref-format(1)</a>
\r
1117 Make sure ref name is well formed.
\r
1121 <a href="git-cherry.html">git-cherry(1)</a>
\r
1125 Find commits not merged upstream.
\r
1129 <a href="git-count-objects.html">git-count-objects(1)</a>
\r
1133 Count unpacked number of objects and their disk consumption.
\r
1137 <a href="git-daemon.html">git-daemon(1)</a>
\r
1141 A really simple server for git repositories.
\r
1145 <a href="git-get-tar-commit-id.html">git-get-tar-commit-id(1)</a>
\r
1149 Extract commit ID from an archive created using git-tar-tree.
\r
1153 <a href="git-mailinfo.html">git-mailinfo(1)</a>
\r
1157 Extracts patch and authorship information from a single
\r
1158 e-mail message, optionally transliterating the commit
\r
1159 message into utf-8.
\r
1163 <a href="git-mailsplit.html">git-mailsplit(1)</a>
\r
1167 A stupid program to split UNIX mbox format mailbox into
\r
1168 individual pieces of e-mail.
\r
1172 <a href="git-patch-id.html">git-patch-id(1)</a>
\r
1176 Compute unique ID for a patch.
\r
1180 <a href="git-parse-remote.html">git-parse-remote(1)</a>
\r
1184 Routines to help parsing <tt>$GIT_DIR/remotes/</tt> files.
\r
1188 <a href="git-request-pull.html">git-request-pull(1)</a>
\r
1196 <a href="git-rev-parse.html">git-rev-parse(1)</a>
\r
1200 Pick out and massage parameters.
\r
1204 <a href="git-send-email.html">git-send-email(1)</a>
\r
1208 Send patch e-mails out of "format-patch --mbox" output.
\r
1212 <a href="git-symbolic-ref.html">git-symbolic-ref(1)</a>
\r
1216 Read and modify symbolic refs.
\r
1220 <a href="git-stripspace.html">git-stripspace(1)</a>
\r
1224 Filter out empty lines.
\r
1229 <h2>Commands not yet documented</h2>
\r
1230 <div class="sectionbody">
\r
1233 <a href="gitk.html">gitk(1)</a>
\r
1237 The gitk repository browser.
\r
1242 <h2>Configuration Mechanism</h2>
\r
1243 <div class="sectionbody">
\r
1244 <p>Starting from 0.99.9 (actually mid 0.99.8.GIT), <tt>.git/config</tt> file
\r
1245 is used to hold per-repository configuration options. It is a
\r
1246 simple text file modelled after <tt>.ini</tt> format familiar to some
\r
1247 people. Here is an example:</p>
\r
1248 <div class="listingblock">
\r
1249 <div class="content">
\r
1251 # A '#' or ';' character indicates a comment.
\r
1256 ; Don't trust file modes
\r
1261 name = "Junio C Hamano"
\r
1262 email = "junkio@twinsun.com"
\r
1265 <p>Various commands read from the configuration file and adjust
\r
1266 their operation accordingly.</p>
\r
1268 <h2>Identifier Terminology</h2>
\r
1269 <div class="sectionbody">
\r
1276 Indicates the object name for any type of object.
\r
1284 Indicates a blob object name.
\r
1292 Indicates a tree object name.
\r
1300 Indicates a commit object name.
\r
1308 Indicates a tree, commit or tag object name. A
\r
1309 command that takes a <tree-ish> argument ultimately wants to
\r
1310 operate on a <tree> object but automatically dereferences
\r
1311 <commit> and <tag> objects that point at a <tree>.
\r
1319 Indicates that an object type is required.
\r
1320 Currently one of: <tt>blob</tt>, <tt>tree</tt>, <tt>commit</tt>, or <tt>tag</tt>.
\r
1328 Indicates a filename - almost always relative to the
\r
1329 root of the tree structure <tt>GIT_INDEX_FILE</tt> describes.
\r
1334 <h2>Symbolic Identifiers</h2>
\r
1335 <div class="sectionbody">
\r
1336 <p>Any git command accepting any <object> can also use the following
\r
1337 symbolic notation:</p>
\r
1344 indicates the head of the current branch (i.e. the
\r
1345 contents of <tt>$GIT_DIR/HEAD</tt>).
\r
1353 a valid tag <em>name</em>
\r
1354 (i.e. the contents of <tt>$GIT_DIR/refs/tags/<tag></tt>).
\r
1362 a valid head <em>name</em>
\r
1363 (i.e. the contents of <tt>$GIT_DIR/refs/heads/<head></tt>).
\r
1371 a valid snapshot <em>name</em>
\r
1372 (i.e. the contents of <tt>$GIT_DIR/refs/snap/<snap></tt>).
\r
1377 <h2>File/Directory Structure</h2>
\r
1378 <div class="sectionbody">
\r
1379 <p>Please see <a href="repository-layout.html">repository layout</a> document.</p>
\r
1380 <p>Higher level SCMs may provide and manage additional information in the
\r
1381 <tt>$GIT_DIR</tt>.</p>
\r
1383 <h2>Terminology</h2>
\r
1384 <div class="sectionbody">
\r
1385 <p>Please see <a href="glossary.html">glossary</a> document.</p>
\r
1387 <h2>Environment Variables</h2>
\r
1388 <div class="sectionbody">
\r
1389 <p>Various git commands use the following environment variables:</p>
\r
1390 <h3>The git Repository</h3>
\r
1391 <p>These environment variables apply to <em>all</em> core git commands. Nb: it
\r
1392 is worth noting that they may be used/overridden by SCMS sitting above
\r
1393 git so take care if using Cogito etc.</p>
\r
1396 <em>GIT_INDEX_FILE</em>
\r
1400 This environment allows the specification of an alternate
\r
1401 index file. If not specified, the default of <tt>$GIT_DIR/index</tt>
\r
1406 <em>GIT_OBJECT_DIRECTORY</em>
\r
1410 If the object storage directory is specified via this
\r
1411 environment variable then the sha1 directories are created
\r
1412 underneath - otherwise the default <tt>$GIT_DIR/objects</tt>
\r
1413 directory is used.
\r
1417 <em>GIT_ALTERNATE_OBJECT_DIRECTORIES</em>
\r
1421 Due to the immutable nature of git objects, old objects can be
\r
1422 archived into shared, read-only directories. This variable
\r
1423 specifies a ":" separated list of git object directories which
\r
1424 can be used to search for git objects. New objects will not be
\r
1425 written to these directories.
\r
1433 If the <em>GIT_DIR</em> environment variable is set then it
\r
1434 specifies a path to use instead of the default <tt>.git</tt>
\r
1435 for the base of the repository.
\r
1439 <h3>git Commits</h3>
\r
1442 <em>GIT_AUTHOR_NAME</em>
\r
1445 <em>GIT_AUTHOR_EMAIL</em>
\r
1448 <em>GIT_AUTHOR_DATE</em>
\r
1451 <em>GIT_COMMITTER_NAME</em>
\r
1454 <em>GIT_COMMITTER_EMAIL</em>
\r
1458 see <a href="git-commit-tree.html">git-commit-tree(1)</a>
\r
1462 <h3>git Diffs</h3>
\r
1465 <em>GIT_DIFF_OPTS</em>
\r
1468 <em>GIT_EXTERNAL_DIFF</em>
\r
1472 see the "generating patches" section in :
\r
1473 <a href="git-diff-index.html">git-diff-index(1)</a>;
\r
1474 <a href="git-diff-files.html">git-diff-files(1)</a>;
\r
1475 <a href="git-diff-tree.html">git-diff-tree(1)</a>
\r
1480 <h2>Discussion<a id="Discussion"></a></h2>
\r
1481 <div class="sectionbody">
\r
1482 <p>"git" can mean anything, depending on your mood.</p>
\r
1486 random three-letter combination that is pronounceable, and not
\r
1487 actually used by any common UNIX command. The fact that it is a
\r
1488 mispronunciation of "get" may or may not be relevant.
\r
1493 stupid. contemptible and despicable. simple. Take your pick from the
\r
1494 dictionary of slang.
\r
1499 "global information tracker": you're in a good mood, and it actually
\r
1500 works for you. Angels sing, and a light suddenly fills the room.
\r
1505 "goddamn idiotic truckload of sh*t": when it breaks
\r
1509 <p>This is a stupid (but extremely fast) directory content manager. It
\r
1510 doesn't do a whole lot, but what it <em>does</em> do is track directory
\r
1511 contents efficiently.</p>
\r
1512 <p>There are two object abstractions: the "object database", and the
\r
1513 "current directory cache" aka "index".</p>
\r
1514 <h3>The Object Database</h3>
\r
1515 <p>The object database is literally just a content-addressable collection
\r
1516 of objects. All objects are named by their content, which is
\r
1517 approximated by the SHA1 hash of the object itself. Objects may refer
\r
1518 to other objects (by referencing their SHA1 hash), and so you can
\r
1519 build up a hierarchy of objects.</p>
\r
1520 <p>All objects have a statically determined "type" aka "tag", which is
\r
1521 determined at object creation time, and which identifies the format of
\r
1522 the object (i.e. how it is used, and how it can refer to other
\r
1523 objects). There are currently four different object types: "blob",
\r
1524 "tree", "commit" and "tag".</p>
\r
1525 <p>A "blob" object cannot refer to any other object, and is, like the type
\r
1526 implies, a pure storage object containing some user data. It is used to
\r
1527 actually store the file data, i.e. a blob object is associated with some
\r
1528 particular version of some file.</p>
\r
1529 <p>A "tree" object is an object that ties one or more "blob" objects into a
\r
1530 directory structure. In addition, a tree object can refer to other tree
\r
1531 objects, thus creating a directory hierarchy.</p>
\r
1532 <p>A "commit" object ties such directory hierarchies together into
\r
1533 a DAG of revisions - each "commit" is associated with exactly one tree
\r
1534 (the directory hierarchy at the time of the commit). In addition, a
\r
1535 "commit" refers to one or more "parent" commit objects that describe the
\r
1536 history of how we arrived at that directory hierarchy.</p>
\r
1537 <p>As a special case, a commit object with no parents is called the "root"
\r
1538 object, and is the point of an initial project commit. Each project
\r
1539 must have at least one root, and while you can tie several different
\r
1540 root objects together into one project by creating a commit object which
\r
1541 has two or more separate roots as its ultimate parents, that's probably
\r
1542 just going to confuse people. So aim for the notion of "one root object
\r
1543 per project", even if git itself does not enforce that.</p>
\r
1544 <p>A "tag" object symbolically identifies and can be used to sign other
\r
1545 objects. It contains the identifier and type of another object, a
\r
1546 symbolic name (of course!) and, optionally, a signature.</p>
\r
1547 <p>Regardless of object type, all objects share the following
\r
1548 characteristics: they are all deflated with zlib, and have a header
\r
1549 that not only specifies their type, but also provides size information
\r
1550 about the data in the object. It's worth noting that the SHA1 hash
\r
1551 that is used to name the object is the hash of the original data
\r
1552 plus this header, so <tt>sha1sum</tt> <em>file</em> does not match the object name
\r
1553 for <em>file</em>.
\r
1554 (Historical note: in the dawn of the age of git the hash
\r
1555 was the sha1 of the <em>compressed</em> object.)</p>
\r
1556 <p>As a result, the general consistency of an object can always be tested
\r
1557 independently of the contents or the type of the object: all objects can
\r
1558 be validated by verifying that (a) their hashes match the content of the
\r
1559 file and (b) the object successfully inflates to a stream of bytes that
\r
1560 forms a sequence of <ascii type without space> + <space> + <ascii decimal
\r
1561 size> + <byte\0> + <binary object data>.</p>
\r
1562 <p>The structured objects can further have their structure and
\r
1563 connectivity to other objects verified. This is generally done with
\r
1564 the <tt>git-fsck-objects</tt> program, which generates a full dependency graph
\r
1565 of all objects, and verifies their internal consistency (in addition
\r
1566 to just verifying their superficial consistency through the hash).</p>
\r
1567 <p>The object types in some more detail:</p>
\r
1568 <h3>Blob Object</h3>
\r
1569 <p>A "blob" object is nothing but a binary blob of data, and doesn't
\r
1570 refer to anything else. There is no signature or any other
\r
1571 verification of the data, so while the object is consistent (it <em>is</em>
\r
1572 indexed by its sha1 hash, so the data itself is certainly correct), it
\r
1573 has absolutely no other attributes. No name associations, no
\r
1574 permissions. It is purely a blob of data (i.e. normally "file
\r
1576 <p>In particular, since the blob is entirely defined by its data, if two
\r
1577 files in a directory tree (or in multiple different versions of the
\r
1578 repository) have the same contents, they will share the same blob
\r
1579 object. The object is totally independent of its location in the
\r
1580 directory tree, and renaming a file does not change the object that
\r
1581 file is associated with in any way.</p>
\r
1582 <p>A blob is typically created when <a href="git-update-index.html">git-update-index(1)</a>
\r
1583 is run, and its data can be accessed by <a href="git-cat-file.html">git-cat-file(1)</a>.</p>
\r
1584 <h3>Tree Object</h3>
\r
1585 <p>The next hierarchical object type is the "tree" object. A tree object
\r
1586 is a list of mode/name/blob data, sorted by name. Alternatively, the
\r
1587 mode data may specify a directory mode, in which case instead of
\r
1588 naming a blob, that name is associated with another TREE object.</p>
\r
1589 <p>Like the "blob" object, a tree object is uniquely determined by the
\r
1590 set contents, and so two separate but identical trees will always
\r
1591 share the exact same object. This is true at all levels, i.e. it's
\r
1592 true for a "leaf" tree (which does not refer to any other trees, only
\r
1593 blobs) as well as for a whole subdirectory.</p>
\r
1594 <p>For that reason a "tree" object is just a pure data abstraction: it
\r
1595 has no history, no signatures, no verification of validity, except
\r
1596 that since the contents are again protected by the hash itself, we can
\r
1597 trust that the tree is immutable and its contents never change.</p>
\r
1598 <p>So you can trust the contents of a tree to be valid, the same way you
\r
1599 can trust the contents of a blob, but you don't know where those
\r
1600 contents <em>came</em> from.</p>
\r
1601 <p>Side note on trees: since a "tree" object is a sorted list of
\r
1602 "filename+content", you can create a diff between two trees without
\r
1603 actually having to unpack two trees. Just ignore all common parts,
\r
1604 and your diff will look right. In other words, you can effectively
\r
1605 (and efficiently) tell the difference between any two random trees by
\r
1606 O(n) where "n" is the size of the difference, rather than the size of
\r
1608 <p>Side note 2 on trees: since the name of a "blob" depends entirely and
\r
1609 exclusively on its contents (i.e. there are no names or permissions
\r
1610 involved), you can see trivial renames or permission changes by
\r
1611 noticing that the blob stayed the same. However, renames with data
\r
1612 changes need a smarter "diff" implementation.</p>
\r
1613 <p>A tree is created with <a href="git-write-tree.html">git-write-tree(1)</a> and
\r
1614 its data can be accessed by <a href="git-ls-tree.html">git-ls-tree(1)</a>.
\r
1615 Two trees can be compared with <a href="git-diff-tree.html">git-diff-tree(1)</a>.</p>
\r
1616 <h3>Commit Object</h3>
\r
1617 <p>The "commit" object is an object that introduces the notion of
\r
1618 history into the picture. In contrast to the other objects, it
\r
1619 doesn't just describe the physical state of a tree, it describes how
\r
1620 we got there, and why.</p>
\r
1621 <p>A "commit" is defined by the tree-object that it results in, the
\r
1622 parent commits (zero, one or more) that led up to that point, and a
\r
1623 comment on what happened. Again, a commit is not trusted per se:
\r
1624 the contents are well-defined and "safe" due to the cryptographically
\r
1625 strong signatures at all levels, but there is no reason to believe
\r
1626 that the tree is "good" or that the merge information makes sense.
\r
1627 The parents do not have to actually have any relationship with the
\r
1628 result, for example.</p>
\r
1629 <p>Note on commits: unlike real SCM's, commits do not contain
\r
1630 rename information or file mode change information. All of that is
\r
1631 implicit in the trees involved (the result tree, and the result trees
\r
1632 of the parents), and describing that makes no sense in this idiotic
\r
1634 <p>A commit is created with <a href="git-commit-tree.html">git-commit-tree(1)</a> and
\r
1635 its data can be accessed by <a href="git-cat-file.html">git-cat-file(1)</a>.</p>
\r
1637 <p>An aside on the notion of "trust". Trust is really outside the scope
\r
1638 of "git", but it's worth noting a few things. First off, since
\r
1639 everything is hashed with SHA1, you <em>can</em> trust that an object is
\r
1640 intact and has not been messed with by external sources. So the name
\r
1641 of an object uniquely identifies a known state - just not a state that
\r
1642 you may want to trust.</p>
\r
1643 <p>Furthermore, since the SHA1 signature of a commit refers to the
\r
1644 SHA1 signatures of the tree it is associated with and the signatures
\r
1645 of the parent, a single named commit specifies uniquely a whole set
\r
1646 of history, with full contents. You can't later fake any step of the
\r
1647 way once you have the name of a commit.</p>
\r
1648 <p>So to introduce some real trust in the system, the only thing you need
\r
1649 to do is to digitally sign just <em>one</em> special note, which includes the
\r
1650 name of a top-level commit. Your digital signature shows others
\r
1651 that you trust that commit, and the immutability of the history of
\r
1652 commits tells others that they can trust the whole history.</p>
\r
1653 <p>In other words, you can easily validate a whole archive by just
\r
1654 sending out a single email that tells the people the name (SHA1 hash)
\r
1655 of the top commit, and digitally sign that email using something
\r
1657 <p>To assist in this, git also provides the tag object…</p>
\r
1658 <h3>Tag Object</h3>
\r
1659 <p>Git provides the "tag" object to simplify creating, managing and
\r
1660 exchanging symbolic and signed tokens. The "tag" object at its
\r
1661 simplest simply symbolically identifies another object by containing
\r
1662 the sha1, type and symbolic name.</p>
\r
1663 <p>However it can optionally contain additional signature information
\r
1664 (which git doesn't care about as long as there's less than 8k of
\r
1665 it). This can then be verified externally to git.</p>
\r
1666 <p>Note that despite the tag features, "git" itself only handles content
\r
1667 integrity; the trust framework (and signature provision and
\r
1668 verification) has to come from outside.</p>
\r
1669 <p>A tag is created with <a href="git-mktag.html">git-mktag(1)</a>,
\r
1670 its data can be accessed by <a href="git-cat-file.html">git-cat-file(1)</a>,
\r
1671 and the signature can be verified by
\r
1672 <a href="git-verify-tag.html">git-verify-tag(1)</a>.</p>
\r
1674 <h2>The "index" aka "Current Directory Cache"</h2>
\r
1675 <div class="sectionbody">
\r
1676 <p>The index is a simple binary file, which contains an efficient
\r
1677 representation of a virtual directory content at some random time. It
\r
1678 does so by a simple array that associates a set of names, dates,
\r
1679 permissions and content (aka "blob") objects together. The cache is
\r
1680 always kept ordered by name, and names are unique (with a few very
\r
1681 specific rules) at any point in time, but the cache has no long-term
\r
1682 meaning, and can be partially updated at any time.</p>
\r
1683 <p>In particular, the index certainly does not need to be consistent with
\r
1684 the current directory contents (in fact, most operations will depend on
\r
1685 different ways to make the index <em>not</em> be consistent with the directory
\r
1686 hierarchy), but it has three very important attributes:</p>
\r
1687 <p><em>(a) it can re-generate the full state it caches (not just the
\r
1688 directory structure: it contains pointers to the "blob" objects so
\r
1689 that it can regenerate the data too)</em></p>
\r
1690 <p>As a special case, there is a clear and unambiguous one-way mapping
\r
1691 from a current directory cache to a "tree object", which can be
\r
1692 efficiently created from just the current directory cache without
\r
1693 actually looking at any other data. So a directory cache at any one
\r
1694 time uniquely specifies one and only one "tree" object (but has
\r
1695 additional data to make it easy to match up that tree object with what
\r
1696 has happened in the directory)</p>
\r
1697 <p><em>(b) it has efficient methods for finding inconsistencies between that
\r
1698 cached state ("tree object waiting to be instantiated") and the
\r
1699 current state.</em></p>
\r
1700 <p><em>(c) it can additionally efficiently represent information about merge
\r
1701 conflicts between different tree objects, allowing each pathname to be
\r
1702 associated with sufficient information about the trees involved that
\r
1703 you can create a three-way merge between them.</em></p>
\r
1704 <p>Those are the three ONLY things that the directory cache does. It's a
\r
1705 cache, and the normal operation is to re-generate it completely from a
\r
1706 known tree object, or update/compare it with a live tree that is being
\r
1707 developed. If you blow the directory cache away entirely, you generally
\r
1708 haven't lost any information as long as you have the name of the tree
\r
1709 that it described.</p>
\r
1710 <p>At the same time, the index is at the same time also the
\r
1711 staging area for creating new trees, and creating a new tree always
\r
1712 involves a controlled modification of the index file. In particular,
\r
1713 the index file can have the representation of an intermediate tree that
\r
1714 has not yet been instantiated. So the index can be thought of as a
\r
1715 write-back cache, which can contain dirty information that has not yet
\r
1716 been written back to the backing store.</p>
\r
1718 <h2>The Workflow</h2>
\r
1719 <div class="sectionbody">
\r
1720 <p>Generally, all "git" operations work on the index file. Some operations
\r
1721 work <strong>purely</strong> on the index file (showing the current state of the
\r
1722 index), but most operations move data to and from the index file. Either
\r
1723 from the database or from the working directory. Thus there are four
\r
1724 main combinations:</p>
\r
1725 <h3>1) working directory -> index</h3>
\r
1726 <p>You update the index with information from the working directory with
\r
1727 the <a href="git-update-index.html">git-update-index(1)</a> command. You
\r
1728 generally update the index information by just specifying the filename
\r
1729 you want to update, like so:</p>
\r
1730 <div class="literalblock">
\r
1731 <div class="content">
\r
1732 <pre><tt>git-update-index filename</tt></pre>
\r
1734 <p>but to avoid common mistakes with filename globbing etc, the command
\r
1735 will not normally add totally new entries or remove old entries,
\r
1736 i.e. it will normally just update existing cache entries.</p>
\r
1737 <p>To tell git that yes, you really do realize that certain files no
\r
1738 longer exist, or that new files should be added, you
\r
1739 should use the <tt>--remove</tt> and <tt>--add</tt> flags respectively.</p>
\r
1740 <p>NOTE! A <tt>--remove</tt> flag does <em>not</em> mean that subsequent filenames will
\r
1741 necessarily be removed: if the files still exist in your directory
\r
1742 structure, the index will be updated with their new status, not
\r
1743 removed. The only thing <tt>--remove</tt> means is that update-cache will be
\r
1744 considering a removed file to be a valid thing, and if the file really
\r
1745 does not exist any more, it will update the index accordingly.</p>
\r
1746 <p>As a special case, you can also do <tt>git-update-index --refresh</tt>, which
\r
1747 will refresh the "stat" information of each index to match the current
\r
1748 stat information. It will <em>not</em> update the object status itself, and
\r
1749 it will only update the fields that are used to quickly test whether
\r
1750 an object still matches its old backing store object.</p>
\r
1751 <h3>2) index -> object database</h3>
\r
1752 <p>You write your current index file to a "tree" object with the program</p>
\r
1753 <div class="literalblock">
\r
1754 <div class="content">
\r
1755 <pre><tt>git-write-tree</tt></pre>
\r
1757 <p>that doesn't come with any options - it will just write out the
\r
1758 current index into the set of tree objects that describe that state,
\r
1759 and it will return the name of the resulting top-level tree. You can
\r
1760 use that tree to re-generate the index at any time by going in the
\r
1761 other direction:</p>
\r
1762 <h3>3) object database -> index</h3>
\r
1763 <p>You read a "tree" file from the object database, and use that to
\r
1764 populate (and overwrite - don't do this if your index contains any
\r
1765 unsaved state that you might want to restore later!) your current
\r
1766 index. Normal operation is just</p>
\r
1767 <div class="literalblock">
\r
1768 <div class="content">
\r
1769 <pre><tt>git-read-tree <sha1 of tree></tt></pre>
\r
1771 <p>and your index file will now be equivalent to the tree that you saved
\r
1772 earlier. However, that is only your <em>index</em> file: your working
\r
1773 directory contents have not been modified.</p>
\r
1774 <h3>4) index -> working directory</h3>
\r
1775 <p>You update your working directory from the index by "checking out"
\r
1776 files. This is not a very common operation, since normally you'd just
\r
1777 keep your files updated, and rather than write to your working
\r
1778 directory, you'd tell the index files about the changes in your
\r
1779 working directory (i.e. <tt>git-update-index</tt>).</p>
\r
1780 <p>However, if you decide to jump to a new version, or check out somebody
\r
1781 else's version, or just restore a previous tree, you'd populate your
\r
1782 index file with read-tree, and then you need to check out the result
\r
1784 <div class="literalblock">
\r
1785 <div class="content">
\r
1786 <pre><tt>git-checkout-index filename</tt></pre>
\r
1788 <p>or, if you want to check out all of the index, use <tt>-a</tt>.</p>
\r
1789 <p>NOTE! git-checkout-index normally refuses to overwrite old files, so
\r
1790 if you have an old version of the tree already checked out, you will
\r
1791 need to use the "-f" flag (<em>before</em> the "-a" flag or the filename) to
\r
1792 <em>force</em> the checkout.</p>
\r
1793 <p>Finally, there are a few odds and ends which are not purely moving
\r
1794 from one representation to the other:</p>
\r
1795 <h3>5) Tying it all together</h3>
\r
1796 <p>To commit a tree you have instantiated with "git-write-tree", you'd
\r
1797 create a "commit" object that refers to that tree and the history
\r
1798 behind it - most notably the "parent" commits that preceded it in
\r
1800 <p>Normally a "commit" has one parent: the previous state of the tree
\r
1801 before a certain change was made. However, sometimes it can have two
\r
1802 or more parent commits, in which case we call it a "merge", due to the
\r
1803 fact that such a commit brings together ("merges") two or more
\r
1804 previous states represented by other commits.</p>
\r
1805 <p>In other words, while a "tree" represents a particular directory state
\r
1806 of a working directory, a "commit" represents that state in "time",
\r
1807 and explains how we got there.</p>
\r
1808 <p>You create a commit object by giving it the tree that describes the
\r
1809 state at the time of the commit, and a list of parents:</p>
\r
1810 <div class="literalblock">
\r
1811 <div class="content">
\r
1812 <pre><tt>git-commit-tree <tree> -p <parent> [-p <parent2> ..]</tt></pre>
\r
1814 <p>and then giving the reason for the commit on stdin (either through
\r
1815 redirection from a pipe or file, or by just typing it at the tty).</p>
\r
1816 <p>git-commit-tree will return the name of the object that represents
\r
1817 that commit, and you should save it away for later use. Normally,
\r
1818 you'd commit a new <tt>HEAD</tt> state, and while git doesn't care where you
\r
1819 save the note about that state, in practice we tend to just write the
\r
1820 result to the file pointed at by <tt>.git/HEAD</tt>, so that we can always see
\r
1821 what the last committed state was.</p>
\r
1822 <p>Here is an ASCII art by Jon Loeliger that illustrates how
\r
1823 various pieces fit together.</p>
\r
1824 <div class="listingblock">
\r
1825 <div class="content">
\r
1851 checkout-index -u | | checkout-index
\r
1860 <h3>6) Examining the data</h3>
\r
1861 <p>You can examine the data represented in the object database and the
\r
1862 index with various helper tools. For every object, you can use
\r
1863 <a href="git-cat-file.html">git-cat-file(1)</a> to examine details about the
\r
1865 <div class="literalblock">
\r
1866 <div class="content">
\r
1867 <pre><tt>git-cat-file -t <objectname></tt></pre>
\r
1869 <p>shows the type of the object, and once you have the type (which is
\r
1870 usually implicit in where you find the object), you can use</p>
\r
1871 <div class="literalblock">
\r
1872 <div class="content">
\r
1873 <pre><tt>git-cat-file blob|tree|commit|tag <objectname></tt></pre>
\r
1875 <p>to show its contents. NOTE! Trees have binary content, and as a result
\r
1876 there is a special helper for showing that content, called
\r
1877 <tt>git-ls-tree</tt>, which turns the binary content into a more easily
\r
1878 readable form.</p>
\r
1879 <p>It's especially instructive to look at "commit" objects, since those
\r
1880 tend to be small and fairly self-explanatory. In particular, if you
\r
1881 follow the convention of having the top commit name in <tt>.git/HEAD</tt>,
\r
1883 <div class="literalblock">
\r
1884 <div class="content">
\r
1885 <pre><tt>git-cat-file commit HEAD</tt></pre>
\r
1887 <p>to see what the top commit was.</p>
\r
1888 <h3>7) Merging multiple trees</h3>
\r
1889 <p>Git helps you do a three-way merge, which you can expand to n-way by
\r
1890 repeating the merge procedure arbitrary times until you finally
\r
1891 "commit" the state. The normal situation is that you'd only do one
\r
1892 three-way merge (two parents), and commit it, but if you like to, you
\r
1893 can do multiple parents in one go.</p>
\r
1894 <p>To do a three-way merge, you need the two sets of "commit" objects
\r
1895 that you want to merge, use those to find the closest common parent (a
\r
1896 third "commit" object), and then use those commit objects to find the
\r
1897 state of the directory ("tree" object) at these points.</p>
\r
1898 <p>To get the "base" for the merge, you first look up the common parent
\r
1899 of two commits with</p>
\r
1900 <div class="literalblock">
\r
1901 <div class="content">
\r
1902 <pre><tt>git-merge-base <commit1> <commit2></tt></pre>
\r
1904 <p>which will return you the commit they are both based on. You should
\r
1905 now look up the "tree" objects of those commits, which you can easily
\r
1906 do with (for example)</p>
\r
1907 <div class="literalblock">
\r
1908 <div class="content">
\r
1909 <pre><tt>git-cat-file commit <commitname> | head -1</tt></pre>
\r
1911 <p>since the tree object information is always the first line in a commit
\r
1913 <p>Once you know the three trees you are going to merge (the one
\r
1914 "original" tree, aka the common case, and the two "result" trees, aka
\r
1915 the branches you want to merge), you do a "merge" read into the
\r
1916 index. This will complain if it has to throw away your old index contents, so you should
\r
1917 make sure that you've committed those - in fact you would normally
\r
1918 always do a merge against your last commit (which should thus match
\r
1919 what you have in your current index anyway).</p>
\r
1920 <p>To do the merge, do</p>
\r
1921 <div class="literalblock">
\r
1922 <div class="content">
\r
1923 <pre><tt>git-read-tree -m -u <origtree> <yourtree> <targettree></tt></pre>
\r
1925 <p>which will do all trivial merge operations for you directly in the
\r
1926 index file, and you can just write the result out with
\r
1927 <tt>git-write-tree</tt>.</p>
\r
1928 <p>Historical note. We did not have <tt>-u</tt> facility when this
\r
1929 section was first written, so we used to warn that
\r
1930 the merge is done in the index file, not in your
\r
1931 working tree, and your working tree will not match your
\r
1932 index after this step.
\r
1933 This is no longer true. The above command, thanks to <tt>-u</tt>
\r
1934 option, updates your working tree with the merge results for
\r
1935 paths that have been trivially merged.</p>
\r
1936 <h3>8) Merging multiple trees, continued</h3>
\r
1937 <p>Sadly, many merges aren't trivial. If there are files that have
\r
1938 been added.moved or removed, or if both branches have modified the
\r
1939 same file, you will be left with an index tree that contains "merge
\r
1940 entries" in it. Such an index tree can <em>NOT</em> be written out to a tree
\r
1941 object, and you will have to resolve any such merge clashes using
\r
1942 other tools before you can write out the result.</p>
\r
1943 <p>You can examine such index state with <tt>git-ls-files --unmerged</tt>
\r
1944 command. An example:</p>
\r
1945 <div class="listingblock">
\r
1946 <div class="content">
\r
1947 <pre><tt>$ git-read-tree -m $orig HEAD $target
\r
1948 $ git-ls-files --unmerged
\r
1949 100644 263414f423d0e4d70dae8fe53fa34614ff3e2860 1 hello.c
\r
1950 100644 06fa6a24256dc7e560efa5687fa84b51f0263c3a 2 hello.c
\r
1951 100644 cc44c73eb783565da5831b4d820c962954019b69 3 hello.c</tt></pre>
\r
1953 <p>Each line of the <tt>git-ls-files --unmerged</tt> output begins with
\r
1954 the blob mode bits, blob SHA1, <em>stage number</em>, and the
\r
1955 filename. The <em>stage number</em> is git's way to say which tree it
\r
1956 came from: stage 1 corresponds to <tt>$orig</tt> tree, stage 2 <tt>HEAD</tt>
\r
1957 tree, and stage3 <tt>$target</tt> tree.</p>
\r
1958 <p>Earlier we said that trivial merges are done inside
\r
1959 <tt>git-read-tree -m</tt>. For example, if the file did not change
\r
1960 from <tt>$orig</tt> to <tt>HEAD</tt> nor <tt>$target</tt>, or if the file changed
\r
1961 from <tt>$orig</tt> to <tt>HEAD</tt> and <tt>$orig</tt> to <tt>$target</tt> the same way,
\r
1962 obviously the final outcome is what is in <tt>HEAD</tt>. What the
\r
1963 above example shows is that file <tt>hello.c</tt> was changed from
\r
1964 <tt>$orig</tt> to <tt>HEAD</tt> and <tt>$orig</tt> to <tt>$target</tt> in a different way.
\r
1965 You could resolve this by running your favorite 3-way merge
\r
1966 program, e.g. <tt>diff3</tt> or <tt>merge</tt>, on the blob objects from
\r
1967 these three stages yourself, like this:</p>
\r
1968 <div class="listingblock">
\r
1969 <div class="content">
\r
1970 <pre><tt>$ git-cat-file blob 263414f... >hello.c~1
\r
1971 $ git-cat-file blob 06fa6a2... >hello.c~2
\r
1972 $ git-cat-file blob cc44c73... >hello.c~3
\r
1973 $ merge hello.c~2 hello.c~1 hello.c~3</tt></pre>
\r
1975 <p>This would leave the merge result in <tt>hello.c~2</tt> file, along
\r
1976 with conflict markers if there are conflicts. After verifying
\r
1977 the merge result makes sense, you can tell git what the final
\r
1978 merge result for this file is by:</p>
\r
1979 <div class="literalblock">
\r
1980 <div class="content">
\r
1981 <pre><tt>mv -f hello.c~2 hello.c
\r
1982 git-update-index hello.c</tt></pre>
\r
1984 <p>When a path is in unmerged state, running <tt>git-update-index</tt> for
\r
1985 that path tells git to mark the path resolved.</p>
\r
1986 <p>The above is the description of a git merge at the lowest level,
\r
1987 to help you understand what conceptually happens under the hood.
\r
1988 In practice, nobody, not even git itself, uses three <tt>git-cat-file</tt>
\r
1989 for this. There is <tt>git-merge-index</tt> program that extracts the
\r
1990 stages to temporary files and calls a "merge" script on it:</p>
\r
1991 <div class="literalblock">
\r
1992 <div class="content">
\r
1993 <pre><tt>git-merge-index git-merge-one-file hello.c</tt></pre>
\r
1995 <p>and that is what higher level <tt>git resolve</tt> is implemented with.</p>
\r
1998 <div class="sectionbody">
\r
2002 git's founding father is Linus Torvalds <torvalds@osdl.org>.
\r
2007 The current git nurse is Junio C Hamano <junkio@cox.net>.
\r
2012 The git potty was written by Andres Ericsson <ae@op5.se>.
\r
2017 General upbringing is handled by the git-list <git@vger.kernel.org>.
\r
2022 <h2>Documentation</h2>
\r
2023 <div class="sectionbody">
\r
2024 <p>The documentation for git suite was started by David Greaves
\r
2025 <david@dgreaves.com>, and later enhanced greatly by the
\r
2026 contributors on the git-list <git@vger.kernel.org>.</p>
\r
2029 <div class="sectionbody">
\r
2030 <p>Part of the <a href="git.html">git(7)</a> suite</p>
\r
2033 <div id="footer-text">
\r
2034 Last updated 07-Feb-2006 08:04:32 UTC
\r
projects / git.git / blob