6 git - the stupid content tracker
12 'git' [--version] [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
13 [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]
14 [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
16 [--help] <command> [<args>]
20 Git is a fast, scalable, distributed revision control system with an
21 unusually rich command set that provides both high-level operations
22 and full access to internals.
24 See linkgit:gittutorial[7] to get started, then see
25 link:everyday.html[Everyday Git] for a useful minimum set of commands, and
26 "man git-commandname" for documentation of each command. CVS users may
27 also want to read linkgit:gitcvs-migration[7]. See
28 the link:user-manual.html[Git User's Manual] for a more in-depth
31 The '<command>' is either a name of a Git command (see below) or an alias
32 as defined in the configuration file (see linkgit:git-config[1]).
34 Formatted and hyperlinked version of the latest git
35 documentation can be viewed at
36 `http://www.kernel.org/pub/software/scm/git/docs/`.
42 You are reading the documentation for the latest (possibly
43 unreleased) version of git, that is available from 'master'
44 branch of the `git.git` repository.
45 Documentation for older releases are available here:
47 * link:v1.7.6.3/git.html[documentation for release 1.7.6.3]
50 link:RelNotes/1.7.6.3.txt[1.7.6.3],
51 link:RelNotes/1.7.6.2.txt[1.7.6.2],
52 link:RelNotes/1.7.6.1.txt[1.7.6.1],
53 link:RelNotes/1.7.6.txt[1.7.6].
55 * link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
58 link:RelNotes/1.7.5.4.txt[1.7.5.4],
59 link:RelNotes/1.7.5.3.txt[1.7.5.3],
60 link:RelNotes/1.7.5.2.txt[1.7.5.2],
61 link:RelNotes/1.7.5.1.txt[1.7.5.1],
62 link:RelNotes/1.7.5.txt[1.7.5].
64 * link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
67 link:RelNotes/1.7.4.5.txt[1.7.4.5],
68 link:RelNotes/1.7.4.4.txt[1.7.4.4],
69 link:RelNotes/1.7.4.3.txt[1.7.4.3],
70 link:RelNotes/1.7.4.2.txt[1.7.4.2],
71 link:RelNotes/1.7.4.1.txt[1.7.4.1],
72 link:RelNotes/1.7.4.txt[1.7.4].
74 * link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
77 link:RelNotes/1.7.3.5.txt[1.7.3.5],
78 link:RelNotes/1.7.3.4.txt[1.7.3.4],
79 link:RelNotes/1.7.3.3.txt[1.7.3.3],
80 link:RelNotes/1.7.3.2.txt[1.7.3.2],
81 link:RelNotes/1.7.3.1.txt[1.7.3.1],
82 link:RelNotes/1.7.3.txt[1.7.3].
84 * link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
87 link:RelNotes/1.7.2.5.txt[1.7.2.5],
88 link:RelNotes/1.7.2.4.txt[1.7.2.4],
89 link:RelNotes/1.7.2.3.txt[1.7.2.3],
90 link:RelNotes/1.7.2.2.txt[1.7.2.2],
91 link:RelNotes/1.7.2.1.txt[1.7.2.1],
92 link:RelNotes/1.7.2.txt[1.7.2].
94 * link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
97 link:RelNotes/1.7.1.4.txt[1.7.1.4],
98 link:RelNotes/1.7.1.3.txt[1.7.1.3],
99 link:RelNotes/1.7.1.2.txt[1.7.1.2],
100 link:RelNotes/1.7.1.1.txt[1.7.1.1],
101 link:RelNotes/1.7.1.txt[1.7.1].
103 * link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
106 link:RelNotes/1.7.0.9.txt[1.7.0.9],
107 link:RelNotes/1.7.0.8.txt[1.7.0.8],
108 link:RelNotes/1.7.0.7.txt[1.7.0.7],
109 link:RelNotes/1.7.0.6.txt[1.7.0.6],
110 link:RelNotes/1.7.0.5.txt[1.7.0.5],
111 link:RelNotes/1.7.0.4.txt[1.7.0.4],
112 link:RelNotes/1.7.0.3.txt[1.7.0.3],
113 link:RelNotes/1.7.0.2.txt[1.7.0.2],
114 link:RelNotes/1.7.0.1.txt[1.7.0.1],
115 link:RelNotes/1.7.0.txt[1.7.0].
117 * link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
120 link:RelNotes/1.6.6.3.txt[1.6.6.3],
121 link:RelNotes/1.6.6.2.txt[1.6.6.2],
122 link:RelNotes/1.6.6.1.txt[1.6.6.1],
123 link:RelNotes/1.6.6.txt[1.6.6].
125 * link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
128 link:RelNotes/1.6.5.9.txt[1.6.5.9],
129 link:RelNotes/1.6.5.8.txt[1.6.5.8],
130 link:RelNotes/1.6.5.7.txt[1.6.5.7],
131 link:RelNotes/1.6.5.6.txt[1.6.5.6],
132 link:RelNotes/1.6.5.5.txt[1.6.5.5],
133 link:RelNotes/1.6.5.4.txt[1.6.5.4],
134 link:RelNotes/1.6.5.3.txt[1.6.5.3],
135 link:RelNotes/1.6.5.2.txt[1.6.5.2],
136 link:RelNotes/1.6.5.1.txt[1.6.5.1],
137 link:RelNotes/1.6.5.txt[1.6.5].
139 * link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
142 link:RelNotes/1.6.4.5.txt[1.6.4.5],
143 link:RelNotes/1.6.4.4.txt[1.6.4.4],
144 link:RelNotes/1.6.4.3.txt[1.6.4.3],
145 link:RelNotes/1.6.4.2.txt[1.6.4.2],
146 link:RelNotes/1.6.4.1.txt[1.6.4.1],
147 link:RelNotes/1.6.4.txt[1.6.4].
149 * link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
152 link:RelNotes/1.6.3.4.txt[1.6.3.4],
153 link:RelNotes/1.6.3.3.txt[1.6.3.3],
154 link:RelNotes/1.6.3.2.txt[1.6.3.2],
155 link:RelNotes/1.6.3.1.txt[1.6.3.1],
156 link:RelNotes/1.6.3.txt[1.6.3].
159 link:RelNotes/1.6.2.5.txt[1.6.2.5],
160 link:RelNotes/1.6.2.4.txt[1.6.2.4],
161 link:RelNotes/1.6.2.3.txt[1.6.2.3],
162 link:RelNotes/1.6.2.2.txt[1.6.2.2],
163 link:RelNotes/1.6.2.1.txt[1.6.2.1],
164 link:RelNotes/1.6.2.txt[1.6.2].
166 * link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
169 link:RelNotes/1.6.1.3.txt[1.6.1.3],
170 link:RelNotes/1.6.1.2.txt[1.6.1.2],
171 link:RelNotes/1.6.1.1.txt[1.6.1.1],
172 link:RelNotes/1.6.1.txt[1.6.1].
174 * link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
177 link:RelNotes/1.6.0.6.txt[1.6.0.6],
178 link:RelNotes/1.6.0.5.txt[1.6.0.5],
179 link:RelNotes/1.6.0.4.txt[1.6.0.4],
180 link:RelNotes/1.6.0.3.txt[1.6.0.3],
181 link:RelNotes/1.6.0.2.txt[1.6.0.2],
182 link:RelNotes/1.6.0.1.txt[1.6.0.1],
183 link:RelNotes/1.6.0.txt[1.6.0].
185 * link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
188 link:RelNotes/1.5.6.6.txt[1.5.6.6],
189 link:RelNotes/1.5.6.5.txt[1.5.6.5],
190 link:RelNotes/1.5.6.4.txt[1.5.6.4],
191 link:RelNotes/1.5.6.3.txt[1.5.6.3],
192 link:RelNotes/1.5.6.2.txt[1.5.6.2],
193 link:RelNotes/1.5.6.1.txt[1.5.6.1],
194 link:RelNotes/1.5.6.txt[1.5.6].
196 * link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
199 link:RelNotes/1.5.5.6.txt[1.5.5.6],
200 link:RelNotes/1.5.5.5.txt[1.5.5.5],
201 link:RelNotes/1.5.5.4.txt[1.5.5.4],
202 link:RelNotes/1.5.5.3.txt[1.5.5.3],
203 link:RelNotes/1.5.5.2.txt[1.5.5.2],
204 link:RelNotes/1.5.5.1.txt[1.5.5.1],
205 link:RelNotes/1.5.5.txt[1.5.5].
207 * link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
210 link:RelNotes/1.5.4.7.txt[1.5.4.7],
211 link:RelNotes/1.5.4.6.txt[1.5.4.6],
212 link:RelNotes/1.5.4.5.txt[1.5.4.5],
213 link:RelNotes/1.5.4.4.txt[1.5.4.4],
214 link:RelNotes/1.5.4.3.txt[1.5.4.3],
215 link:RelNotes/1.5.4.2.txt[1.5.4.2],
216 link:RelNotes/1.5.4.1.txt[1.5.4.1],
217 link:RelNotes/1.5.4.txt[1.5.4].
219 * link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
222 link:RelNotes/1.5.3.8.txt[1.5.3.8],
223 link:RelNotes/1.5.3.7.txt[1.5.3.7],
224 link:RelNotes/1.5.3.6.txt[1.5.3.6],
225 link:RelNotes/1.5.3.5.txt[1.5.3.5],
226 link:RelNotes/1.5.3.4.txt[1.5.3.4],
227 link:RelNotes/1.5.3.3.txt[1.5.3.3],
228 link:RelNotes/1.5.3.2.txt[1.5.3.2],
229 link:RelNotes/1.5.3.1.txt[1.5.3.1],
230 link:RelNotes/1.5.3.txt[1.5.3].
232 * link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
235 link:RelNotes/1.5.2.5.txt[1.5.2.5],
236 link:RelNotes/1.5.2.4.txt[1.5.2.4],
237 link:RelNotes/1.5.2.3.txt[1.5.2.3],
238 link:RelNotes/1.5.2.2.txt[1.5.2.2],
239 link:RelNotes/1.5.2.1.txt[1.5.2.1],
240 link:RelNotes/1.5.2.txt[1.5.2].
242 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
245 link:RelNotes/1.5.1.6.txt[1.5.1.6],
246 link:RelNotes/1.5.1.5.txt[1.5.1.5],
247 link:RelNotes/1.5.1.4.txt[1.5.1.4],
248 link:RelNotes/1.5.1.3.txt[1.5.1.3],
249 link:RelNotes/1.5.1.2.txt[1.5.1.2],
250 link:RelNotes/1.5.1.1.txt[1.5.1.1],
251 link:RelNotes/1.5.1.txt[1.5.1].
253 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
256 link:RelNotes/1.5.0.7.txt[1.5.0.7],
257 link:RelNotes/1.5.0.6.txt[1.5.0.6],
258 link:RelNotes/1.5.0.5.txt[1.5.0.5],
259 link:RelNotes/1.5.0.3.txt[1.5.0.3],
260 link:RelNotes/1.5.0.2.txt[1.5.0.2],
261 link:RelNotes/1.5.0.1.txt[1.5.0.1],
262 link:RelNotes/1.5.0.txt[1.5.0].
264 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
265 link:v1.3.3/git.html[1.3.3],
266 link:v1.2.6/git.html[1.2.6],
267 link:v1.0.13/git.html[1.0.13].
276 Prints the git suite version that the 'git' program came from.
279 Prints the synopsis and a list of the most commonly used
280 commands. If the option '--all' or '-a' is given then all
281 available commands are printed. If a git command is named this
282 option will bring up the manual page for that command.
284 Other options are available to control how the manual page is
285 displayed. See linkgit:git-help[1] for more information,
286 because `git --help ...` is converted internally into `git
290 Pass a configuration parameter to the command. The value
291 given will override values from configuration files.
292 The <name> is expected in the same format as listed by
293 'git config' (subkeys separated by dots).
295 --exec-path[=<path>]::
296 Path to wherever your core git programs are installed.
297 This can also be controlled by setting the GIT_EXEC_PATH
298 environment variable. If no path is given, 'git' will print
299 the current setting and then exit.
302 Print the path, without trailing slash, where git's HTML
303 documentation is installed and exit.
306 Print the manpath (see `man(1)`) for the man pages for
307 this version of git and exit.
310 Print the path where the Info files documenting this
311 version of git are installed and exit.
315 Pipe all output into 'less' (or if set, $PAGER) if standard
316 output is a terminal. This overrides the `pager.<cmd>`
317 configuration options (see the "Configuration Mechanism" section
321 Do not pipe git output into a pager.
324 Set the path to the repository. This can also be controlled by
325 setting the GIT_DIR environment variable. It can be an absolute
326 path or relative path to current working directory.
329 Set the path to the working tree. It can be an absolute path
330 or a path relative to the current working directory.
331 This can also be controlled by setting the GIT_WORK_TREE
332 environment variable and the core.worktree configuration
333 variable (see core.worktree in linkgit:git-config[1] for a
334 more detailed discussion).
337 Set the git namespace. See linkgit:gitnamespaces[7] for more
338 details. Equivalent to setting the `GIT_NAMESPACE` environment
342 Treat the repository as a bare repository. If GIT_DIR
343 environment is not set, it is set to the current working
346 --no-replace-objects::
347 Do not use replacement refs to replace git objects. See
348 linkgit:git-replace[1] for more information.
351 FURTHER DOCUMENTATION
352 ---------------------
354 See the references above to get started using git. The following is
355 probably more detail than necessary for a first-time user.
357 The link:user-manual.html#git-concepts[git concepts chapter of the
358 user-manual] and linkgit:gitcore-tutorial[7] both provide
359 introductions to the underlying git architecture.
361 See linkgit:gitworkflows[7] for an overview of recommended workflows.
363 See also the link:howto-index.html[howto] documents for some useful
366 The internals are documented in the
367 link:technical/api-index.html[GIT API documentation].
372 We divide git into high level ("porcelain") commands and low level
373 ("plumbing") commands.
375 High-level commands (porcelain)
376 -------------------------------
378 We separate the porcelain commands into the main commands and some
379 ancillary user utilities.
381 Main porcelain commands
382 ~~~~~~~~~~~~~~~~~~~~~~~
384 include::cmds-mainporcelain.txt[]
390 include::cmds-ancillarymanipulators.txt[]
394 include::cmds-ancillaryinterrogators.txt[]
397 Interacting with Others
398 ~~~~~~~~~~~~~~~~~~~~~~~
400 These commands are to interact with foreign SCM and with other
401 people via patch over e-mail.
403 include::cmds-foreignscminterface.txt[]
406 Low-level commands (plumbing)
407 -----------------------------
409 Although git includes its
410 own porcelain layer, its low-level commands are sufficient to support
411 development of alternative porcelains. Developers of such porcelains
412 might start by reading about linkgit:git-update-index[1] and
413 linkgit:git-read-tree[1].
415 The interface (input, output, set of options and the semantics)
416 to these low-level commands are meant to be a lot more stable
417 than Porcelain level commands, because these commands are
418 primarily for scripted use. The interface to Porcelain commands
419 on the other hand are subject to change in order to improve the
422 The following description divides
423 the low-level commands into commands that manipulate objects (in
424 the repository, index, and working tree), commands that interrogate and
425 compare objects, and commands that move objects and references between
429 Manipulation commands
430 ~~~~~~~~~~~~~~~~~~~~~
432 include::cmds-plumbingmanipulators.txt[]
435 Interrogation commands
436 ~~~~~~~~~~~~~~~~~~~~~~
438 include::cmds-plumbinginterrogators.txt[]
440 In general, the interrogate commands do not touch the files in
444 Synching repositories
445 ~~~~~~~~~~~~~~~~~~~~~
447 include::cmds-synchingrepositories.txt[]
449 The following are helper commands used by the above; end users
450 typically do not use them directly.
452 include::cmds-synchelpers.txt[]
455 Internal helper commands
456 ~~~~~~~~~~~~~~~~~~~~~~~~
458 These are internal helper commands used by other commands; end
459 users typically do not use them directly.
461 include::cmds-purehelpers.txt[]
464 Configuration Mechanism
465 -----------------------
467 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
468 is used to hold per-repository configuration options. It is a
469 simple text file modeled after `.ini` format familiar to some
470 people. Here is an example:
474 # A '#' or ';' character indicates a comment.
479 ; Don't trust file modes
484 name = "Junio C Hamano"
485 email = "junkio@twinsun.com"
489 Various commands read from the configuration file and adjust
490 their operation accordingly. See linkgit:git-config[1] for a
494 Identifier Terminology
495 ----------------------
497 Indicates the object name for any type of object.
500 Indicates a blob object name.
503 Indicates a tree object name.
506 Indicates a commit object name.
509 Indicates a tree, commit or tag object name. A
510 command that takes a <tree-ish> argument ultimately wants to
511 operate on a <tree> object but automatically dereferences
512 <commit> and <tag> objects that point at a <tree>.
515 Indicates a commit or tag object name. A
516 command that takes a <commit-ish> argument ultimately wants to
517 operate on a <commit> object but automatically dereferences
518 <tag> objects that point at a <commit>.
521 Indicates that an object type is required.
522 Currently one of: `blob`, `tree`, `commit`, or `tag`.
525 Indicates a filename - almost always relative to the
526 root of the tree structure `GIT_INDEX_FILE` describes.
530 Any git command accepting any <object> can also use the following
534 indicates the head of the current branch.
538 (i.e. a `refs/tags/<tag>` reference).
542 (i.e. a `refs/heads/<head>` reference).
544 For a more complete list of ways to spell object names, see
545 "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
548 File/Directory Structure
549 ------------------------
551 Please see the linkgit:gitrepository-layout[5] document.
553 Read linkgit:githooks[5] for more details about each hook.
555 Higher level SCMs may provide and manage additional information in the
561 Please see linkgit:gitglossary[7].
564 Environment Variables
565 ---------------------
566 Various git commands use the following environment variables:
570 These environment variables apply to 'all' core git commands. Nb: it
571 is worth noting that they may be used/overridden by SCMS sitting above
572 git so take care if using Cogito etc.
575 This environment allows the specification of an alternate
576 index file. If not specified, the default of `$GIT_DIR/index`
579 'GIT_OBJECT_DIRECTORY'::
580 If the object storage directory is specified via this
581 environment variable then the sha1 directories are created
582 underneath - otherwise the default `$GIT_DIR/objects`
585 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
586 Due to the immutable nature of git objects, old objects can be
587 archived into shared, read-only directories. This variable
588 specifies a ":" separated (on Windows ";" separated) list
589 of git object directories which can be used to search for git
590 objects. New objects will not be written to these directories.
593 If the 'GIT_DIR' environment variable is set then it
594 specifies a path to use instead of the default `.git`
595 for the base of the repository.
598 Set the path to the working tree. The value will not be
599 used in combination with repositories found automatically in
600 a .git directory (i.e. $GIT_DIR is not set).
601 This can also be controlled by the '--work-tree' command line
602 option and the core.worktree configuration variable.
605 Set the git namespace; see linkgit:gitnamespaces[7] for details.
606 The '--namespace' command-line option also sets this value.
608 'GIT_CEILING_DIRECTORIES'::
609 This should be a colon-separated list of absolute paths.
610 If set, it is a list of directories that git should not chdir
611 up into while looking for a repository directory.
612 It will not exclude the current working directory or
613 a GIT_DIR set on the command line or in the environment.
614 (Useful for excluding slow-loading network directories.)
616 'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
617 When run in a directory that does not have ".git" repository
618 directory, git tries to find such a directory in the parent
619 directories to find the top of the working tree, but by default it
620 does not cross filesystem boundaries. This environment variable
621 can be set to true to tell git not to stop at filesystem
622 boundaries. Like 'GIT_CEILING_DIRECTORIES', this will not affect
623 an explicit repository directory set via 'GIT_DIR' or on the
631 'GIT_COMMITTER_NAME'::
632 'GIT_COMMITTER_EMAIL'::
633 'GIT_COMMITTER_DATE'::
635 see linkgit:git-commit-tree[1]
640 Only valid setting is "--unified=??" or "-u??" to set the
641 number of context lines shown when a unified diff is created.
642 This takes precedence over any "-U" or "--unified" option
643 value passed on the git diff command line.
645 'GIT_EXTERNAL_DIFF'::
646 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
647 program named by it is called, instead of the diff invocation
648 described above. For a path that is added, removed, or modified,
649 'GIT_EXTERNAL_DIFF' is called with 7 parameters:
651 path old-file old-hex old-mode new-file new-hex new-mode
655 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
656 contents of <old|new>,
657 <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
658 <old|new>-mode:: are the octal representation of the file modes.
660 The file parameters can point at the user's working file
661 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
662 when a new file is added), or a temporary file (e.g. `old-file` in the
663 index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
664 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
666 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
671 'GIT_MERGE_VERBOSITY'::
672 A number controlling the amount of output shown by
673 the recursive merge strategy. Overrides merge.verbosity.
674 See linkgit:git-merge[1]
677 This environment variable overrides `$PAGER`. If it is set
678 to an empty string or to the value "cat", git will not launch
679 a pager. See also the `core.pager` option in
680 linkgit:git-config[1].
683 If this environment variable is set then 'git fetch'
684 and 'git push' will use this command instead
685 of 'ssh' when they need to connect to a remote system.
686 The '$GIT_SSH' command will be given exactly two arguments:
687 the 'username@host' (or just 'host') from the URL and the
688 shell command to execute on that remote system.
690 To pass options to the program that you want to list in GIT_SSH
691 you will need to wrap the program and options into a shell script,
692 then set GIT_SSH to refer to the shell script.
694 Usually it is easier to configure any desired options through your
695 personal `.ssh/config` file. Please consult your ssh documentation
699 If this environment variable is set, then git commands which need to
700 acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
701 will call this program with a suitable prompt as command line argument
702 and read the password from its STDOUT. See also the 'core.askpass'
703 option in linkgit:git-config[1].
706 If this environment variable is set to "1", then commands such
707 as 'git blame' (in incremental mode), 'git rev-list', 'git log',
708 and 'git whatchanged' will force a flush of the output stream
709 after each commit-oriented record have been flushed. If this
710 variable is set to "0", the output of these commands will be done
711 using completely buffered I/O. If this environment variable is
712 not set, git will choose buffered or record-oriented flushing
713 based on whether stdout appears to be redirected to a file or not.
716 If this variable is set to "1", "2" or "true" (comparison
717 is case insensitive), git will print `trace:` messages on
718 stderr telling about alias expansion, built-in command
719 execution and external command execution.
720 If this variable is set to an integer value greater than 1
721 and lower than 10 (strictly) then git will interpret this
722 value as an open file descriptor and will try to write the
723 trace messages into this file descriptor.
724 Alternatively, if this variable is set to an absolute path
725 (starting with a '/' character), git will interpret this
726 as a file path and will try to write the trace messages
729 Discussion[[Discussion]]
730 ------------------------
732 More detail on the following is available from the
733 link:user-manual.html#git-concepts[git concepts chapter of the
734 user-manual] and linkgit:gitcore-tutorial[7].
736 A git project normally consists of a working directory with a ".git"
737 subdirectory at the top level. The .git directory contains, among other
738 things, a compressed object database representing the complete history
739 of the project, an "index" file which links that history to the current
740 contents of the working tree, and named pointers into that history such
741 as tags and branch heads.
743 The object database contains objects of three main types: blobs, which
744 hold file data; trees, which point to blobs and other trees to build up
745 directory hierarchies; and commits, which each reference a single tree
746 and some number of parent commits.
748 The commit, equivalent to what other systems call a "changeset" or
749 "version", represents a step in the project's history, and each parent
750 represents an immediately preceding step. Commits with more than one
751 parent represent merges of independent lines of development.
753 All objects are named by the SHA1 hash of their contents, normally
754 written as a string of 40 hex digits. Such names are globally unique.
755 The entire history leading up to a commit can be vouched for by signing
756 just that commit. A fourth object type, the tag, is provided for this
759 When first created, objects are stored in individual files, but for
760 efficiency may later be compressed together into "pack files".
762 Named pointers called refs mark interesting points in history. A ref
763 may contain the SHA1 name of an object or the name of another ref. Refs
764 with names beginning `ref/head/` contain the SHA1 name of the most
765 recent commit (or "head") of a branch under development. SHA1 names of
766 tags of interest are stored under `ref/tags/`. A special ref named
767 `HEAD` contains the name of the currently checked-out branch.
769 The index file is initialized with a list of all paths and, for each
770 path, a blob object and a set of attributes. The blob object represents
771 the contents of the file as of the head of the current branch. The
772 attributes (last modified time, size, etc.) are taken from the
773 corresponding file in the working tree. Subsequent changes to the
774 working tree can be found by comparing these attributes. The index may
775 be updated with new content, and new commits may be created from the
776 content stored in the index.
778 The index is also capable of storing multiple entries (called "stages")
779 for a given pathname. These stages are used to hold the various
780 unmerged version of a file when a merge is in progress.
784 Git was started by Linus Torvalds, and is currently maintained by Junio
785 C Hamano. Numerous contributions have come from the git mailing list
786 <git@vger.kernel.org>. For a more complete list of contributors, see
787 http://git-scm.com/about. If you have a clone of git.git itself, the
788 output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
789 the authors for specific parts of the project.
794 Report bugs to the Git mailing list <git@vger.kernel.org> where the
795 development and maintenance is primarily done. You do not have to be
796 subscribed to the list to send a message there.
800 linkgit:gittutorial[7], linkgit:gittutorial-2[7],
801 link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
802 linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
803 linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
804 linkgit:gitworkflows[7]
808 Part of the linkgit:git[1] suite