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:v1.7.8.3/git.html[documentation for release 1.7.8.3]
50 link:RelNotes/1.7.8.3.txt[1.7.8.3],
51 link:RelNotes/1.7.8.2.txt[1.7.8.2],
52 link:RelNotes/1.7.8.1.txt[1.7.8.1],
53 link:RelNotes/1.7.8.txt[1.7.8].
55 * link:v1.7.7.5/git.html[documentation for release 1.7.7.5]
58 link:RelNotes/1.7.7.5.txt[1.7.7.5],
59 link:RelNotes/1.7.7.4.txt[1.7.7.4],
60 link:RelNotes/1.7.7.3.txt[1.7.7.3],
61 link:RelNotes/1.7.7.2.txt[1.7.7.2],
62 link:RelNotes/1.7.7.1.txt[1.7.7.1],
63 link:RelNotes/1.7.7.txt[1.7.7].
65 * link:v1.7.6.5/git.html[documentation for release 1.7.6.5]
68 link:RelNotes/1.7.6.5.txt[1.7.6.5],
69 link:RelNotes/1.7.6.4.txt[1.7.6.4],
70 link:RelNotes/1.7.6.3.txt[1.7.6.3],
71 link:RelNotes/1.7.6.2.txt[1.7.6.2],
72 link:RelNotes/1.7.6.1.txt[1.7.6.1],
73 link:RelNotes/1.7.6.txt[1.7.6].
75 * link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
78 link:RelNotes/1.7.5.4.txt[1.7.5.4],
79 link:RelNotes/1.7.5.3.txt[1.7.5.3],
80 link:RelNotes/1.7.5.2.txt[1.7.5.2],
81 link:RelNotes/1.7.5.1.txt[1.7.5.1],
82 link:RelNotes/1.7.5.txt[1.7.5].
84 * link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
87 link:RelNotes/1.7.4.5.txt[1.7.4.5],
88 link:RelNotes/1.7.4.4.txt[1.7.4.4],
89 link:RelNotes/1.7.4.3.txt[1.7.4.3],
90 link:RelNotes/1.7.4.2.txt[1.7.4.2],
91 link:RelNotes/1.7.4.1.txt[1.7.4.1],
92 link:RelNotes/1.7.4.txt[1.7.4].
94 * link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
97 link:RelNotes/1.7.3.5.txt[1.7.3.5],
98 link:RelNotes/1.7.3.4.txt[1.7.3.4],
99 link:RelNotes/1.7.3.3.txt[1.7.3.3],
100 link:RelNotes/1.7.3.2.txt[1.7.3.2],
101 link:RelNotes/1.7.3.1.txt[1.7.3.1],
102 link:RelNotes/1.7.3.txt[1.7.3].
104 * link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
107 link:RelNotes/1.7.2.5.txt[1.7.2.5],
108 link:RelNotes/1.7.2.4.txt[1.7.2.4],
109 link:RelNotes/1.7.2.3.txt[1.7.2.3],
110 link:RelNotes/1.7.2.2.txt[1.7.2.2],
111 link:RelNotes/1.7.2.1.txt[1.7.2.1],
112 link:RelNotes/1.7.2.txt[1.7.2].
114 * link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
117 link:RelNotes/1.7.1.4.txt[1.7.1.4],
118 link:RelNotes/1.7.1.3.txt[1.7.1.3],
119 link:RelNotes/1.7.1.2.txt[1.7.1.2],
120 link:RelNotes/1.7.1.1.txt[1.7.1.1],
121 link:RelNotes/1.7.1.txt[1.7.1].
123 * link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
126 link:RelNotes/1.7.0.9.txt[1.7.0.9],
127 link:RelNotes/1.7.0.8.txt[1.7.0.8],
128 link:RelNotes/1.7.0.7.txt[1.7.0.7],
129 link:RelNotes/1.7.0.6.txt[1.7.0.6],
130 link:RelNotes/1.7.0.5.txt[1.7.0.5],
131 link:RelNotes/1.7.0.4.txt[1.7.0.4],
132 link:RelNotes/1.7.0.3.txt[1.7.0.3],
133 link:RelNotes/1.7.0.2.txt[1.7.0.2],
134 link:RelNotes/1.7.0.1.txt[1.7.0.1],
135 link:RelNotes/1.7.0.txt[1.7.0].
137 * link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
140 link:RelNotes/1.6.6.3.txt[1.6.6.3],
141 link:RelNotes/1.6.6.2.txt[1.6.6.2],
142 link:RelNotes/1.6.6.1.txt[1.6.6.1],
143 link:RelNotes/1.6.6.txt[1.6.6].
145 * link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
148 link:RelNotes/1.6.5.9.txt[1.6.5.9],
149 link:RelNotes/1.6.5.8.txt[1.6.5.8],
150 link:RelNotes/1.6.5.7.txt[1.6.5.7],
151 link:RelNotes/1.6.5.6.txt[1.6.5.6],
152 link:RelNotes/1.6.5.5.txt[1.6.5.5],
153 link:RelNotes/1.6.5.4.txt[1.6.5.4],
154 link:RelNotes/1.6.5.3.txt[1.6.5.3],
155 link:RelNotes/1.6.5.2.txt[1.6.5.2],
156 link:RelNotes/1.6.5.1.txt[1.6.5.1],
157 link:RelNotes/1.6.5.txt[1.6.5].
159 * link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
162 link:RelNotes/1.6.4.5.txt[1.6.4.5],
163 link:RelNotes/1.6.4.4.txt[1.6.4.4],
164 link:RelNotes/1.6.4.3.txt[1.6.4.3],
165 link:RelNotes/1.6.4.2.txt[1.6.4.2],
166 link:RelNotes/1.6.4.1.txt[1.6.4.1],
167 link:RelNotes/1.6.4.txt[1.6.4].
169 * link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
172 link:RelNotes/1.6.3.4.txt[1.6.3.4],
173 link:RelNotes/1.6.3.3.txt[1.6.3.3],
174 link:RelNotes/1.6.3.2.txt[1.6.3.2],
175 link:RelNotes/1.6.3.1.txt[1.6.3.1],
176 link:RelNotes/1.6.3.txt[1.6.3].
179 link:RelNotes/1.6.2.5.txt[1.6.2.5],
180 link:RelNotes/1.6.2.4.txt[1.6.2.4],
181 link:RelNotes/1.6.2.3.txt[1.6.2.3],
182 link:RelNotes/1.6.2.2.txt[1.6.2.2],
183 link:RelNotes/1.6.2.1.txt[1.6.2.1],
184 link:RelNotes/1.6.2.txt[1.6.2].
186 * link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
189 link:RelNotes/1.6.1.3.txt[1.6.1.3],
190 link:RelNotes/1.6.1.2.txt[1.6.1.2],
191 link:RelNotes/1.6.1.1.txt[1.6.1.1],
192 link:RelNotes/1.6.1.txt[1.6.1].
194 * link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
197 link:RelNotes/1.6.0.6.txt[1.6.0.6],
198 link:RelNotes/1.6.0.5.txt[1.6.0.5],
199 link:RelNotes/1.6.0.4.txt[1.6.0.4],
200 link:RelNotes/1.6.0.3.txt[1.6.0.3],
201 link:RelNotes/1.6.0.2.txt[1.6.0.2],
202 link:RelNotes/1.6.0.1.txt[1.6.0.1],
203 link:RelNotes/1.6.0.txt[1.6.0].
205 * link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
208 link:RelNotes/1.5.6.6.txt[1.5.6.6],
209 link:RelNotes/1.5.6.5.txt[1.5.6.5],
210 link:RelNotes/1.5.6.4.txt[1.5.6.4],
211 link:RelNotes/1.5.6.3.txt[1.5.6.3],
212 link:RelNotes/1.5.6.2.txt[1.5.6.2],
213 link:RelNotes/1.5.6.1.txt[1.5.6.1],
214 link:RelNotes/1.5.6.txt[1.5.6].
216 * link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
219 link:RelNotes/1.5.5.6.txt[1.5.5.6],
220 link:RelNotes/1.5.5.5.txt[1.5.5.5],
221 link:RelNotes/1.5.5.4.txt[1.5.5.4],
222 link:RelNotes/1.5.5.3.txt[1.5.5.3],
223 link:RelNotes/1.5.5.2.txt[1.5.5.2],
224 link:RelNotes/1.5.5.1.txt[1.5.5.1],
225 link:RelNotes/1.5.5.txt[1.5.5].
227 * link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
230 link:RelNotes/1.5.4.7.txt[1.5.4.7],
231 link:RelNotes/1.5.4.6.txt[1.5.4.6],
232 link:RelNotes/1.5.4.5.txt[1.5.4.5],
233 link:RelNotes/1.5.4.4.txt[1.5.4.4],
234 link:RelNotes/1.5.4.3.txt[1.5.4.3],
235 link:RelNotes/1.5.4.2.txt[1.5.4.2],
236 link:RelNotes/1.5.4.1.txt[1.5.4.1],
237 link:RelNotes/1.5.4.txt[1.5.4].
239 * link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
242 link:RelNotes/1.5.3.8.txt[1.5.3.8],
243 link:RelNotes/1.5.3.7.txt[1.5.3.7],
244 link:RelNotes/1.5.3.6.txt[1.5.3.6],
245 link:RelNotes/1.5.3.5.txt[1.5.3.5],
246 link:RelNotes/1.5.3.4.txt[1.5.3.4],
247 link:RelNotes/1.5.3.3.txt[1.5.3.3],
248 link:RelNotes/1.5.3.2.txt[1.5.3.2],
249 link:RelNotes/1.5.3.1.txt[1.5.3.1],
250 link:RelNotes/1.5.3.txt[1.5.3].
252 * link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
255 link:RelNotes/1.5.2.5.txt[1.5.2.5],
256 link:RelNotes/1.5.2.4.txt[1.5.2.4],
257 link:RelNotes/1.5.2.3.txt[1.5.2.3],
258 link:RelNotes/1.5.2.2.txt[1.5.2.2],
259 link:RelNotes/1.5.2.1.txt[1.5.2.1],
260 link:RelNotes/1.5.2.txt[1.5.2].
262 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
265 link:RelNotes/1.5.1.6.txt[1.5.1.6],
266 link:RelNotes/1.5.1.5.txt[1.5.1.5],
267 link:RelNotes/1.5.1.4.txt[1.5.1.4],
268 link:RelNotes/1.5.1.3.txt[1.5.1.3],
269 link:RelNotes/1.5.1.2.txt[1.5.1.2],
270 link:RelNotes/1.5.1.1.txt[1.5.1.1],
271 link:RelNotes/1.5.1.txt[1.5.1].
273 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
276 link:RelNotes/1.5.0.7.txt[1.5.0.7],
277 link:RelNotes/1.5.0.6.txt[1.5.0.6],
278 link:RelNotes/1.5.0.5.txt[1.5.0.5],
279 link:RelNotes/1.5.0.3.txt[1.5.0.3],
280 link:RelNotes/1.5.0.2.txt[1.5.0.2],
281 link:RelNotes/1.5.0.1.txt[1.5.0.1],
282 link:RelNotes/1.5.0.txt[1.5.0].
284 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
285 link:v1.3.3/git.html[1.3.3],
286 link:v1.2.6/git.html[1.2.6],
287 link:v1.0.13/git.html[1.0.13].
296 Prints the git suite version that the 'git' program came from.
299 Prints the synopsis and a list of the most commonly used
300 commands. If the option '--all' or '-a' is given then all
301 available commands are printed. If a git command is named this
302 option will bring up the manual page for that command.
304 Other options are available to control how the manual page is
305 displayed. See linkgit:git-help[1] for more information,
306 because `git --help ...` is converted internally into `git
310 Pass a configuration parameter to the command. The value
311 given will override values from configuration files.
312 The <name> is expected in the same format as listed by
313 'git config' (subkeys separated by dots).
315 --exec-path[=<path>]::
316 Path to wherever your core git programs are installed.
317 This can also be controlled by setting the GIT_EXEC_PATH
318 environment variable. If no path is given, 'git' will print
319 the current setting and then exit.
322 Print the path, without trailing slash, where git's HTML
323 documentation is installed and exit.
326 Print the manpath (see `man(1)`) for the man pages for
327 this version of git and exit.
330 Print the path where the Info files documenting this
331 version of git are installed and exit.
335 Pipe all output into 'less' (or if set, $PAGER) if standard
336 output is a terminal. This overrides the `pager.<cmd>`
337 configuration options (see the "Configuration Mechanism" section
341 Do not pipe git output into a pager.
344 Set the path to the repository. This can also be controlled by
345 setting the GIT_DIR environment variable. It can be an absolute
346 path or relative path to current working directory.
349 Set the path to the working tree. It can be an absolute path
350 or a path relative to the current working directory.
351 This can also be controlled by setting the GIT_WORK_TREE
352 environment variable and the core.worktree configuration
353 variable (see core.worktree in linkgit:git-config[1] for a
354 more detailed discussion).
357 Set the git namespace. See linkgit:gitnamespaces[7] for more
358 details. Equivalent to setting the `GIT_NAMESPACE` environment
362 Treat the repository as a bare repository. If GIT_DIR
363 environment is not set, it is set to the current working
366 --no-replace-objects::
367 Do not use replacement refs to replace git objects. See
368 linkgit:git-replace[1] for more information.
371 FURTHER DOCUMENTATION
372 ---------------------
374 See the references above to get started using git. The following is
375 probably more detail than necessary for a first-time user.
377 The link:user-manual.html#git-concepts[git concepts chapter of the
378 user-manual] and linkgit:gitcore-tutorial[7] both provide
379 introductions to the underlying git architecture.
381 See linkgit:gitworkflows[7] for an overview of recommended workflows.
383 See also the link:howto-index.html[howto] documents for some useful
386 The internals are documented in the
387 link:technical/api-index.html[GIT API documentation].
392 We divide git into high level ("porcelain") commands and low level
393 ("plumbing") commands.
395 High-level commands (porcelain)
396 -------------------------------
398 We separate the porcelain commands into the main commands and some
399 ancillary user utilities.
401 Main porcelain commands
402 ~~~~~~~~~~~~~~~~~~~~~~~
404 include::cmds-mainporcelain.txt[]
410 include::cmds-ancillarymanipulators.txt[]
414 include::cmds-ancillaryinterrogators.txt[]
417 Interacting with Others
418 ~~~~~~~~~~~~~~~~~~~~~~~
420 These commands are to interact with foreign SCM and with other
421 people via patch over e-mail.
423 include::cmds-foreignscminterface.txt[]
426 Low-level commands (plumbing)
427 -----------------------------
429 Although git includes its
430 own porcelain layer, its low-level commands are sufficient to support
431 development of alternative porcelains. Developers of such porcelains
432 might start by reading about linkgit:git-update-index[1] and
433 linkgit:git-read-tree[1].
435 The interface (input, output, set of options and the semantics)
436 to these low-level commands are meant to be a lot more stable
437 than Porcelain level commands, because these commands are
438 primarily for scripted use. The interface to Porcelain commands
439 on the other hand are subject to change in order to improve the
442 The following description divides
443 the low-level commands into commands that manipulate objects (in
444 the repository, index, and working tree), commands that interrogate and
445 compare objects, and commands that move objects and references between
449 Manipulation commands
450 ~~~~~~~~~~~~~~~~~~~~~
452 include::cmds-plumbingmanipulators.txt[]
455 Interrogation commands
456 ~~~~~~~~~~~~~~~~~~~~~~
458 include::cmds-plumbinginterrogators.txt[]
460 In general, the interrogate commands do not touch the files in
464 Synching repositories
465 ~~~~~~~~~~~~~~~~~~~~~
467 include::cmds-synchingrepositories.txt[]
469 The following are helper commands used by the above; end users
470 typically do not use them directly.
472 include::cmds-synchelpers.txt[]
475 Internal helper commands
476 ~~~~~~~~~~~~~~~~~~~~~~~~
478 These are internal helper commands used by other commands; end
479 users typically do not use them directly.
481 include::cmds-purehelpers.txt[]
484 Configuration Mechanism
485 -----------------------
487 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
488 is used to hold per-repository configuration options. It is a
489 simple text file modeled after `.ini` format familiar to some
490 people. Here is an example:
494 # A '#' or ';' character indicates a comment.
499 ; Don't trust file modes
504 name = "Junio C Hamano"
505 email = "junkio@twinsun.com"
509 Various commands read from the configuration file and adjust
510 their operation accordingly. See linkgit:git-config[1] for a
514 Identifier Terminology
515 ----------------------
517 Indicates the object name for any type of object.
520 Indicates a blob object name.
523 Indicates a tree object name.
526 Indicates a commit object name.
529 Indicates a tree, commit or tag object name. A
530 command that takes a <tree-ish> argument ultimately wants to
531 operate on a <tree> object but automatically dereferences
532 <commit> and <tag> objects that point at a <tree>.
535 Indicates a commit or tag object name. A
536 command that takes a <commit-ish> argument ultimately wants to
537 operate on a <commit> object but automatically dereferences
538 <tag> objects that point at a <commit>.
541 Indicates that an object type is required.
542 Currently one of: `blob`, `tree`, `commit`, or `tag`.
545 Indicates a filename - almost always relative to the
546 root of the tree structure `GIT_INDEX_FILE` describes.
550 Any git command accepting any <object> can also use the following
554 indicates the head of the current branch.
558 (i.e. a `refs/tags/<tag>` reference).
562 (i.e. a `refs/heads/<head>` reference).
564 For a more complete list of ways to spell object names, see
565 "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
568 File/Directory Structure
569 ------------------------
571 Please see the linkgit:gitrepository-layout[5] document.
573 Read linkgit:githooks[5] for more details about each hook.
575 Higher level SCMs may provide and manage additional information in the
581 Please see linkgit:gitglossary[7].
584 Environment Variables
585 ---------------------
586 Various git commands use the following environment variables:
590 These environment variables apply to 'all' core git commands. Nb: it
591 is worth noting that they may be used/overridden by SCMS sitting above
592 git so take care if using Cogito etc.
595 This environment allows the specification of an alternate
596 index file. If not specified, the default of `$GIT_DIR/index`
599 'GIT_OBJECT_DIRECTORY'::
600 If the object storage directory is specified via this
601 environment variable then the sha1 directories are created
602 underneath - otherwise the default `$GIT_DIR/objects`
605 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
606 Due to the immutable nature of git objects, old objects can be
607 archived into shared, read-only directories. This variable
608 specifies a ":" separated (on Windows ";" separated) list
609 of git object directories which can be used to search for git
610 objects. New objects will not be written to these directories.
613 If the 'GIT_DIR' environment variable is set then it
614 specifies a path to use instead of the default `.git`
615 for the base of the repository.
618 Set the path to the working tree. The value will not be
619 used in combination with repositories found automatically in
620 a .git directory (i.e. $GIT_DIR is not set).
621 This can also be controlled by the '--work-tree' command line
622 option and the core.worktree configuration variable.
625 Set the git namespace; see linkgit:gitnamespaces[7] for details.
626 The '--namespace' command-line option also sets this value.
628 'GIT_CEILING_DIRECTORIES'::
629 This should be a colon-separated list of absolute paths.
630 If set, it is a list of directories that git should not chdir
631 up into while looking for a repository directory.
632 It will not exclude the current working directory or
633 a GIT_DIR set on the command line or in the environment.
634 (Useful for excluding slow-loading network directories.)
636 'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
637 When run in a directory that does not have ".git" repository
638 directory, git tries to find such a directory in the parent
639 directories to find the top of the working tree, but by default it
640 does not cross filesystem boundaries. This environment variable
641 can be set to true to tell git not to stop at filesystem
642 boundaries. Like 'GIT_CEILING_DIRECTORIES', this will not affect
643 an explicit repository directory set via 'GIT_DIR' or on the
651 'GIT_COMMITTER_NAME'::
652 'GIT_COMMITTER_EMAIL'::
653 'GIT_COMMITTER_DATE'::
655 see linkgit:git-commit-tree[1]
660 Only valid setting is "--unified=??" or "-u??" to set the
661 number of context lines shown when a unified diff is created.
662 This takes precedence over any "-U" or "--unified" option
663 value passed on the git diff command line.
665 'GIT_EXTERNAL_DIFF'::
666 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
667 program named by it is called, instead of the diff invocation
668 described above. For a path that is added, removed, or modified,
669 'GIT_EXTERNAL_DIFF' is called with 7 parameters:
671 path old-file old-hex old-mode new-file new-hex new-mode
675 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
676 contents of <old|new>,
677 <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
678 <old|new>-mode:: are the octal representation of the file modes.
680 The file parameters can point at the user's working file
681 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
682 when a new file is added), or a temporary file (e.g. `old-file` in the
683 index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
684 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
686 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
691 'GIT_MERGE_VERBOSITY'::
692 A number controlling the amount of output shown by
693 the recursive merge strategy. Overrides merge.verbosity.
694 See linkgit:git-merge[1]
697 This environment variable overrides `$PAGER`. If it is set
698 to an empty string or to the value "cat", git will not launch
699 a pager. See also the `core.pager` option in
700 linkgit:git-config[1].
703 If this environment variable is set then 'git fetch'
704 and 'git push' will use this command instead
705 of 'ssh' when they need to connect to a remote system.
706 The '$GIT_SSH' command will be given exactly two arguments:
707 the 'username@host' (or just 'host') from the URL and the
708 shell command to execute on that remote system.
710 To pass options to the program that you want to list in GIT_SSH
711 you will need to wrap the program and options into a shell script,
712 then set GIT_SSH to refer to the shell script.
714 Usually it is easier to configure any desired options through your
715 personal `.ssh/config` file. Please consult your ssh documentation
719 If this environment variable is set, then git commands which need to
720 acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
721 will call this program with a suitable prompt as command line argument
722 and read the password from its STDOUT. See also the 'core.askpass'
723 option in linkgit:git-config[1].
726 If this environment variable is set to "1", then commands such
727 as 'git blame' (in incremental mode), 'git rev-list', 'git log',
728 and 'git whatchanged' will force a flush of the output stream
729 after each commit-oriented record have been flushed. If this
730 variable is set to "0", the output of these commands will be done
731 using completely buffered I/O. If this environment variable is
732 not set, git will choose buffered or record-oriented flushing
733 based on whether stdout appears to be redirected to a file or not.
736 If this variable is set to "1", "2" or "true" (comparison
737 is case insensitive), git will print `trace:` messages on
738 stderr telling about alias expansion, built-in command
739 execution and external command execution.
740 If this variable is set to an integer value greater than 1
741 and lower than 10 (strictly) then git will interpret this
742 value as an open file descriptor and will try to write the
743 trace messages into this file descriptor.
744 Alternatively, if this variable is set to an absolute path
745 (starting with a '/' character), git will interpret this
746 as a file path and will try to write the trace messages
749 Discussion[[Discussion]]
750 ------------------------
752 More detail on the following is available from the
753 link:user-manual.html#git-concepts[git concepts chapter of the
754 user-manual] and linkgit:gitcore-tutorial[7].
756 A git project normally consists of a working directory with a ".git"
757 subdirectory at the top level. The .git directory contains, among other
758 things, a compressed object database representing the complete history
759 of the project, an "index" file which links that history to the current
760 contents of the working tree, and named pointers into that history such
761 as tags and branch heads.
763 The object database contains objects of three main types: blobs, which
764 hold file data; trees, which point to blobs and other trees to build up
765 directory hierarchies; and commits, which each reference a single tree
766 and some number of parent commits.
768 The commit, equivalent to what other systems call a "changeset" or
769 "version", represents a step in the project's history, and each parent
770 represents an immediately preceding step. Commits with more than one
771 parent represent merges of independent lines of development.
773 All objects are named by the SHA1 hash of their contents, normally
774 written as a string of 40 hex digits. Such names are globally unique.
775 The entire history leading up to a commit can be vouched for by signing
776 just that commit. A fourth object type, the tag, is provided for this
779 When first created, objects are stored in individual files, but for
780 efficiency may later be compressed together into "pack files".
782 Named pointers called refs mark interesting points in history. A ref
783 may contain the SHA1 name of an object or the name of another ref. Refs
784 with names beginning `ref/head/` contain the SHA1 name of the most
785 recent commit (or "head") of a branch under development. SHA1 names of
786 tags of interest are stored under `ref/tags/`. A special ref named
787 `HEAD` contains the name of the currently checked-out branch.
789 The index file is initialized with a list of all paths and, for each
790 path, a blob object and a set of attributes. The blob object represents
791 the contents of the file as of the head of the current branch. The
792 attributes (last modified time, size, etc.) are taken from the
793 corresponding file in the working tree. Subsequent changes to the
794 working tree can be found by comparing these attributes. The index may
795 be updated with new content, and new commits may be created from the
796 content stored in the index.
798 The index is also capable of storing multiple entries (called "stages")
799 for a given pathname. These stages are used to hold the various
800 unmerged version of a file when a merge is in progress.
804 Git was started by Linus Torvalds, and is currently maintained by Junio
805 C Hamano. Numerous contributions have come from the git mailing list
806 <git@vger.kernel.org>. For a more complete list of contributors, see
807 http://git-scm.com/about. If you have a clone of git.git itself, the
808 output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
809 the authors for specific parts of the project.
814 Report bugs to the Git mailing list <git@vger.kernel.org> where the
815 development and maintenance is primarily done. You do not have to be
816 subscribed to the list to send a message there.
820 linkgit:gittutorial[7], linkgit:gittutorial-2[7],
821 link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
822 linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
823 linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
824 linkgit:gitworkflows[7]
828 Part of the linkgit:git[1] suite