sh-setup: work around "unset IFS" bug in some shells
[git/git.git] / Documentation / git.txt
1 git(1)
2 ======
3
4 NAME
5 ----
6 git - the stupid content tracker
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git' [--version] [--help] [-c <name>=<value>]
13 [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
14 [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]
15 [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
16 <command> [<args>]
17
18 DESCRIPTION
19 -----------
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.
23
24 See linkgit:gittutorial[7] to get started, then see
25 link:everyday.html[Everyday Git] for a useful minimum set of
26 commands. The link:user-manual.html[Git User's Manual] has a more
27 in-depth introduction.
28
29 After you mastered the basic concepts, you can come back to this
30 page to learn what commands git offers. You can learn more about
31 individual git commands with "git help command". linkgit:gitcli[7]
32 manual page gives you an overview of the command line command syntax.
33
34 Formatted and hyperlinked version of the latest git documentation
35 can be viewed at `http://git-htmldocs.googlecode.com/git/git.html`.
36
37 ifdef::stalenotes[]
38 [NOTE]
39 ============
40
41 You are reading the documentation for the latest (possibly
42 unreleased) version of git, that is available from 'master'
43 branch of the `git.git` repository.
44 Documentation for older releases are available here:
45
46 * link:v1.8.0.1/git.html[documentation for release 1.8.0.1]
47
48 * release notes for
49 link:RelNotes/1.8.0.1.txt[1.8.0.1],
50 link:RelNotes/1.8.0.txt[1.8.0].
51
52 * link:v1.7.12.4/git.html[documentation for release 1.7.12.4]
53
54 * release notes for
55 link:RelNotes/1.7.12.4.txt[1.7.12.4],
56 link:RelNotes/1.7.12.3.txt[1.7.12.3],
57 link:RelNotes/1.7.12.2.txt[1.7.12.2],
58 link:RelNotes/1.7.12.1.txt[1.7.12.1],
59 link:RelNotes/1.7.12.txt[1.7.12].
60
61 * link:v1.7.11.7/git.html[documentation for release 1.7.11.7]
62
63 * release notes for
64 link:RelNotes/1.7.11.7.txt[1.7.11.7],
65 link:RelNotes/1.7.11.6.txt[1.7.11.6],
66 link:RelNotes/1.7.11.5.txt[1.7.11.5],
67 link:RelNotes/1.7.11.4.txt[1.7.11.4],
68 link:RelNotes/1.7.11.3.txt[1.7.11.3],
69 link:RelNotes/1.7.11.2.txt[1.7.11.2],
70 link:RelNotes/1.7.11.1.txt[1.7.11.1],
71 link:RelNotes/1.7.11.txt[1.7.11].
72
73 * link:v1.7.10.5/git.html[documentation for release 1.7.10.5]
74
75 * release notes for
76 link:RelNotes/1.7.10.5.txt[1.7.10.5],
77 link:RelNotes/1.7.10.4.txt[1.7.10.4],
78 link:RelNotes/1.7.10.3.txt[1.7.10.3],
79 link:RelNotes/1.7.10.2.txt[1.7.10.2],
80 link:RelNotes/1.7.10.1.txt[1.7.10.1],
81 link:RelNotes/1.7.10.txt[1.7.10].
82
83 * link:v1.7.9.7/git.html[documentation for release 1.7.9.7]
84
85 * release notes for
86 link:RelNotes/1.7.9.7.txt[1.7.9.7],
87 link:RelNotes/1.7.9.6.txt[1.7.9.6],
88 link:RelNotes/1.7.9.5.txt[1.7.9.5],
89 link:RelNotes/1.7.9.4.txt[1.7.9.4],
90 link:RelNotes/1.7.9.3.txt[1.7.9.3],
91 link:RelNotes/1.7.9.2.txt[1.7.9.2],
92 link:RelNotes/1.7.9.1.txt[1.7.9.1],
93 link:RelNotes/1.7.9.txt[1.7.9].
94
95 * link:v1.7.8.6/git.html[documentation for release 1.7.8.6]
96
97 * release notes for
98 link:RelNotes/1.7.8.6.txt[1.7.8.6],
99 link:RelNotes/1.7.8.5.txt[1.7.8.5],
100 link:RelNotes/1.7.8.4.txt[1.7.8.4],
101 link:RelNotes/1.7.8.3.txt[1.7.8.3],
102 link:RelNotes/1.7.8.2.txt[1.7.8.2],
103 link:RelNotes/1.7.8.1.txt[1.7.8.1],
104 link:RelNotes/1.7.8.txt[1.7.8].
105
106 * link:v1.7.7.7/git.html[documentation for release 1.7.7.7]
107
108 * release notes for
109 link:RelNotes/1.7.7.7.txt[1.7.7.7],
110 link:RelNotes/1.7.7.6.txt[1.7.7.6],
111 link:RelNotes/1.7.7.5.txt[1.7.7.5],
112 link:RelNotes/1.7.7.4.txt[1.7.7.4],
113 link:RelNotes/1.7.7.3.txt[1.7.7.3],
114 link:RelNotes/1.7.7.2.txt[1.7.7.2],
115 link:RelNotes/1.7.7.1.txt[1.7.7.1],
116 link:RelNotes/1.7.7.txt[1.7.7].
117
118 * link:v1.7.6.6/git.html[documentation for release 1.7.6.6]
119
120 * release notes for
121 link:RelNotes/1.7.6.6.txt[1.7.6.6],
122 link:RelNotes/1.7.6.5.txt[1.7.6.5],
123 link:RelNotes/1.7.6.4.txt[1.7.6.4],
124 link:RelNotes/1.7.6.3.txt[1.7.6.3],
125 link:RelNotes/1.7.6.2.txt[1.7.6.2],
126 link:RelNotes/1.7.6.1.txt[1.7.6.1],
127 link:RelNotes/1.7.6.txt[1.7.6].
128
129 * link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
130
131 * release notes for
132 link:RelNotes/1.7.5.4.txt[1.7.5.4],
133 link:RelNotes/1.7.5.3.txt[1.7.5.3],
134 link:RelNotes/1.7.5.2.txt[1.7.5.2],
135 link:RelNotes/1.7.5.1.txt[1.7.5.1],
136 link:RelNotes/1.7.5.txt[1.7.5].
137
138 * link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
139
140 * release notes for
141 link:RelNotes/1.7.4.5.txt[1.7.4.5],
142 link:RelNotes/1.7.4.4.txt[1.7.4.4],
143 link:RelNotes/1.7.4.3.txt[1.7.4.3],
144 link:RelNotes/1.7.4.2.txt[1.7.4.2],
145 link:RelNotes/1.7.4.1.txt[1.7.4.1],
146 link:RelNotes/1.7.4.txt[1.7.4].
147
148 * link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
149
150 * release notes for
151 link:RelNotes/1.7.3.5.txt[1.7.3.5],
152 link:RelNotes/1.7.3.4.txt[1.7.3.4],
153 link:RelNotes/1.7.3.3.txt[1.7.3.3],
154 link:RelNotes/1.7.3.2.txt[1.7.3.2],
155 link:RelNotes/1.7.3.1.txt[1.7.3.1],
156 link:RelNotes/1.7.3.txt[1.7.3].
157
158 * link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
159
160 * release notes for
161 link:RelNotes/1.7.2.5.txt[1.7.2.5],
162 link:RelNotes/1.7.2.4.txt[1.7.2.4],
163 link:RelNotes/1.7.2.3.txt[1.7.2.3],
164 link:RelNotes/1.7.2.2.txt[1.7.2.2],
165 link:RelNotes/1.7.2.1.txt[1.7.2.1],
166 link:RelNotes/1.7.2.txt[1.7.2].
167
168 * link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
169
170 * release notes for
171 link:RelNotes/1.7.1.4.txt[1.7.1.4],
172 link:RelNotes/1.7.1.3.txt[1.7.1.3],
173 link:RelNotes/1.7.1.2.txt[1.7.1.2],
174 link:RelNotes/1.7.1.1.txt[1.7.1.1],
175 link:RelNotes/1.7.1.txt[1.7.1].
176
177 * link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
178
179 * release notes for
180 link:RelNotes/1.7.0.9.txt[1.7.0.9],
181 link:RelNotes/1.7.0.8.txt[1.7.0.8],
182 link:RelNotes/1.7.0.7.txt[1.7.0.7],
183 link:RelNotes/1.7.0.6.txt[1.7.0.6],
184 link:RelNotes/1.7.0.5.txt[1.7.0.5],
185 link:RelNotes/1.7.0.4.txt[1.7.0.4],
186 link:RelNotes/1.7.0.3.txt[1.7.0.3],
187 link:RelNotes/1.7.0.2.txt[1.7.0.2],
188 link:RelNotes/1.7.0.1.txt[1.7.0.1],
189 link:RelNotes/1.7.0.txt[1.7.0].
190
191 * link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
192
193 * release notes for
194 link:RelNotes/1.6.6.3.txt[1.6.6.3],
195 link:RelNotes/1.6.6.2.txt[1.6.6.2],
196 link:RelNotes/1.6.6.1.txt[1.6.6.1],
197 link:RelNotes/1.6.6.txt[1.6.6].
198
199 * link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
200
201 * release notes for
202 link:RelNotes/1.6.5.9.txt[1.6.5.9],
203 link:RelNotes/1.6.5.8.txt[1.6.5.8],
204 link:RelNotes/1.6.5.7.txt[1.6.5.7],
205 link:RelNotes/1.6.5.6.txt[1.6.5.6],
206 link:RelNotes/1.6.5.5.txt[1.6.5.5],
207 link:RelNotes/1.6.5.4.txt[1.6.5.4],
208 link:RelNotes/1.6.5.3.txt[1.6.5.3],
209 link:RelNotes/1.6.5.2.txt[1.6.5.2],
210 link:RelNotes/1.6.5.1.txt[1.6.5.1],
211 link:RelNotes/1.6.5.txt[1.6.5].
212
213 * link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
214
215 * release notes for
216 link:RelNotes/1.6.4.5.txt[1.6.4.5],
217 link:RelNotes/1.6.4.4.txt[1.6.4.4],
218 link:RelNotes/1.6.4.3.txt[1.6.4.3],
219 link:RelNotes/1.6.4.2.txt[1.6.4.2],
220 link:RelNotes/1.6.4.1.txt[1.6.4.1],
221 link:RelNotes/1.6.4.txt[1.6.4].
222
223 * link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
224
225 * release notes for
226 link:RelNotes/1.6.3.4.txt[1.6.3.4],
227 link:RelNotes/1.6.3.3.txt[1.6.3.3],
228 link:RelNotes/1.6.3.2.txt[1.6.3.2],
229 link:RelNotes/1.6.3.1.txt[1.6.3.1],
230 link:RelNotes/1.6.3.txt[1.6.3].
231
232 * release notes for
233 link:RelNotes/1.6.2.5.txt[1.6.2.5],
234 link:RelNotes/1.6.2.4.txt[1.6.2.4],
235 link:RelNotes/1.6.2.3.txt[1.6.2.3],
236 link:RelNotes/1.6.2.2.txt[1.6.2.2],
237 link:RelNotes/1.6.2.1.txt[1.6.2.1],
238 link:RelNotes/1.6.2.txt[1.6.2].
239
240 * link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
241
242 * release notes for
243 link:RelNotes/1.6.1.3.txt[1.6.1.3],
244 link:RelNotes/1.6.1.2.txt[1.6.1.2],
245 link:RelNotes/1.6.1.1.txt[1.6.1.1],
246 link:RelNotes/1.6.1.txt[1.6.1].
247
248 * link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
249
250 * release notes for
251 link:RelNotes/1.6.0.6.txt[1.6.0.6],
252 link:RelNotes/1.6.0.5.txt[1.6.0.5],
253 link:RelNotes/1.6.0.4.txt[1.6.0.4],
254 link:RelNotes/1.6.0.3.txt[1.6.0.3],
255 link:RelNotes/1.6.0.2.txt[1.6.0.2],
256 link:RelNotes/1.6.0.1.txt[1.6.0.1],
257 link:RelNotes/1.6.0.txt[1.6.0].
258
259 * link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
260
261 * release notes for
262 link:RelNotes/1.5.6.6.txt[1.5.6.6],
263 link:RelNotes/1.5.6.5.txt[1.5.6.5],
264 link:RelNotes/1.5.6.4.txt[1.5.6.4],
265 link:RelNotes/1.5.6.3.txt[1.5.6.3],
266 link:RelNotes/1.5.6.2.txt[1.5.6.2],
267 link:RelNotes/1.5.6.1.txt[1.5.6.1],
268 link:RelNotes/1.5.6.txt[1.5.6].
269
270 * link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
271
272 * release notes for
273 link:RelNotes/1.5.5.6.txt[1.5.5.6],
274 link:RelNotes/1.5.5.5.txt[1.5.5.5],
275 link:RelNotes/1.5.5.4.txt[1.5.5.4],
276 link:RelNotes/1.5.5.3.txt[1.5.5.3],
277 link:RelNotes/1.5.5.2.txt[1.5.5.2],
278 link:RelNotes/1.5.5.1.txt[1.5.5.1],
279 link:RelNotes/1.5.5.txt[1.5.5].
280
281 * link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
282
283 * release notes for
284 link:RelNotes/1.5.4.7.txt[1.5.4.7],
285 link:RelNotes/1.5.4.6.txt[1.5.4.6],
286 link:RelNotes/1.5.4.5.txt[1.5.4.5],
287 link:RelNotes/1.5.4.4.txt[1.5.4.4],
288 link:RelNotes/1.5.4.3.txt[1.5.4.3],
289 link:RelNotes/1.5.4.2.txt[1.5.4.2],
290 link:RelNotes/1.5.4.1.txt[1.5.4.1],
291 link:RelNotes/1.5.4.txt[1.5.4].
292
293 * link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
294
295 * release notes for
296 link:RelNotes/1.5.3.8.txt[1.5.3.8],
297 link:RelNotes/1.5.3.7.txt[1.5.3.7],
298 link:RelNotes/1.5.3.6.txt[1.5.3.6],
299 link:RelNotes/1.5.3.5.txt[1.5.3.5],
300 link:RelNotes/1.5.3.4.txt[1.5.3.4],
301 link:RelNotes/1.5.3.3.txt[1.5.3.3],
302 link:RelNotes/1.5.3.2.txt[1.5.3.2],
303 link:RelNotes/1.5.3.1.txt[1.5.3.1],
304 link:RelNotes/1.5.3.txt[1.5.3].
305
306 * link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
307
308 * release notes for
309 link:RelNotes/1.5.2.5.txt[1.5.2.5],
310 link:RelNotes/1.5.2.4.txt[1.5.2.4],
311 link:RelNotes/1.5.2.3.txt[1.5.2.3],
312 link:RelNotes/1.5.2.2.txt[1.5.2.2],
313 link:RelNotes/1.5.2.1.txt[1.5.2.1],
314 link:RelNotes/1.5.2.txt[1.5.2].
315
316 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
317
318 * release notes for
319 link:RelNotes/1.5.1.6.txt[1.5.1.6],
320 link:RelNotes/1.5.1.5.txt[1.5.1.5],
321 link:RelNotes/1.5.1.4.txt[1.5.1.4],
322 link:RelNotes/1.5.1.3.txt[1.5.1.3],
323 link:RelNotes/1.5.1.2.txt[1.5.1.2],
324 link:RelNotes/1.5.1.1.txt[1.5.1.1],
325 link:RelNotes/1.5.1.txt[1.5.1].
326
327 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
328
329 * release notes for
330 link:RelNotes/1.5.0.7.txt[1.5.0.7],
331 link:RelNotes/1.5.0.6.txt[1.5.0.6],
332 link:RelNotes/1.5.0.5.txt[1.5.0.5],
333 link:RelNotes/1.5.0.3.txt[1.5.0.3],
334 link:RelNotes/1.5.0.2.txt[1.5.0.2],
335 link:RelNotes/1.5.0.1.txt[1.5.0.1],
336 link:RelNotes/1.5.0.txt[1.5.0].
337
338 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
339 link:v1.3.3/git.html[1.3.3],
340 link:v1.2.6/git.html[1.2.6],
341 link:v1.0.13/git.html[1.0.13].
342
343 ============
344
345 endif::stalenotes[]
346
347 OPTIONS
348 -------
349 --version::
350 Prints the git suite version that the 'git' program came from.
351
352 --help::
353 Prints the synopsis and a list of the most commonly used
354 commands. If the option '--all' or '-a' is given then all
355 available commands are printed. If a git command is named this
356 option will bring up the manual page for that command.
357 +
358 Other options are available to control how the manual page is
359 displayed. See linkgit:git-help[1] for more information,
360 because `git --help ...` is converted internally into `git
361 help ...`.
362
363 -c <name>=<value>::
364 Pass a configuration parameter to the command. The value
365 given will override values from configuration files.
366 The <name> is expected in the same format as listed by
367 'git config' (subkeys separated by dots).
368
369 --exec-path[=<path>]::
370 Path to wherever your core git programs are installed.
371 This can also be controlled by setting the GIT_EXEC_PATH
372 environment variable. If no path is given, 'git' will print
373 the current setting and then exit.
374
375 --html-path::
376 Print the path, without trailing slash, where git's HTML
377 documentation is installed and exit.
378
379 --man-path::
380 Print the manpath (see `man(1)`) for the man pages for
381 this version of git and exit.
382
383 --info-path::
384 Print the path where the Info files documenting this
385 version of git are installed and exit.
386
387 -p::
388 --paginate::
389 Pipe all output into 'less' (or if set, $PAGER) if standard
390 output is a terminal. This overrides the `pager.<cmd>`
391 configuration options (see the "Configuration Mechanism" section
392 below).
393
394 --no-pager::
395 Do not pipe git output into a pager.
396
397 --git-dir=<path>::
398 Set the path to the repository. This can also be controlled by
399 setting the GIT_DIR environment variable. It can be an absolute
400 path or relative path to current working directory.
401
402 --work-tree=<path>::
403 Set the path to the working tree. It can be an absolute path
404 or a path relative to the current working directory.
405 This can also be controlled by setting the GIT_WORK_TREE
406 environment variable and the core.worktree configuration
407 variable (see core.worktree in linkgit:git-config[1] for a
408 more detailed discussion).
409
410 --namespace=<path>::
411 Set the git namespace. See linkgit:gitnamespaces[7] for more
412 details. Equivalent to setting the `GIT_NAMESPACE` environment
413 variable.
414
415 --bare::
416 Treat the repository as a bare repository. If GIT_DIR
417 environment is not set, it is set to the current working
418 directory.
419
420 --no-replace-objects::
421 Do not use replacement refs to replace git objects. See
422 linkgit:git-replace[1] for more information.
423
424
425 GIT COMMANDS
426 ------------
427
428 We divide git into high level ("porcelain") commands and low level
429 ("plumbing") commands.
430
431 High-level commands (porcelain)
432 -------------------------------
433
434 We separate the porcelain commands into the main commands and some
435 ancillary user utilities.
436
437 Main porcelain commands
438 ~~~~~~~~~~~~~~~~~~~~~~~
439
440 include::cmds-mainporcelain.txt[]
441
442 Ancillary Commands
443 ~~~~~~~~~~~~~~~~~~
444 Manipulators:
445
446 include::cmds-ancillarymanipulators.txt[]
447
448 Interrogators:
449
450 include::cmds-ancillaryinterrogators.txt[]
451
452
453 Interacting with Others
454 ~~~~~~~~~~~~~~~~~~~~~~~
455
456 These commands are to interact with foreign SCM and with other
457 people via patch over e-mail.
458
459 include::cmds-foreignscminterface.txt[]
460
461
462 Low-level commands (plumbing)
463 -----------------------------
464
465 Although git includes its
466 own porcelain layer, its low-level commands are sufficient to support
467 development of alternative porcelains. Developers of such porcelains
468 might start by reading about linkgit:git-update-index[1] and
469 linkgit:git-read-tree[1].
470
471 The interface (input, output, set of options and the semantics)
472 to these low-level commands are meant to be a lot more stable
473 than Porcelain level commands, because these commands are
474 primarily for scripted use. The interface to Porcelain commands
475 on the other hand are subject to change in order to improve the
476 end user experience.
477
478 The following description divides
479 the low-level commands into commands that manipulate objects (in
480 the repository, index, and working tree), commands that interrogate and
481 compare objects, and commands that move objects and references between
482 repositories.
483
484
485 Manipulation commands
486 ~~~~~~~~~~~~~~~~~~~~~
487
488 include::cmds-plumbingmanipulators.txt[]
489
490
491 Interrogation commands
492 ~~~~~~~~~~~~~~~~~~~~~~
493
494 include::cmds-plumbinginterrogators.txt[]
495
496 In general, the interrogate commands do not touch the files in
497 the working tree.
498
499
500 Synching repositories
501 ~~~~~~~~~~~~~~~~~~~~~
502
503 include::cmds-synchingrepositories.txt[]
504
505 The following are helper commands used by the above; end users
506 typically do not use them directly.
507
508 include::cmds-synchelpers.txt[]
509
510
511 Internal helper commands
512 ~~~~~~~~~~~~~~~~~~~~~~~~
513
514 These are internal helper commands used by other commands; end
515 users typically do not use them directly.
516
517 include::cmds-purehelpers.txt[]
518
519
520 Configuration Mechanism
521 -----------------------
522
523 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
524 is used to hold per-repository configuration options. It is a
525 simple text file modeled after `.ini` format familiar to some
526 people. Here is an example:
527
528 ------------
529 #
530 # A '#' or ';' character indicates a comment.
531 #
532
533 ; core variables
534 [core]
535 ; Don't trust file modes
536 filemode = false
537
538 ; user identity
539 [user]
540 name = "Junio C Hamano"
541 email = "junkio@twinsun.com"
542
543 ------------
544
545 Various commands read from the configuration file and adjust
546 their operation accordingly. See linkgit:git-config[1] for a
547 list.
548
549
550 Identifier Terminology
551 ----------------------
552 <object>::
553 Indicates the object name for any type of object.
554
555 <blob>::
556 Indicates a blob object name.
557
558 <tree>::
559 Indicates a tree object name.
560
561 <commit>::
562 Indicates a commit object name.
563
564 <tree-ish>::
565 Indicates a tree, commit or tag object name. A
566 command that takes a <tree-ish> argument ultimately wants to
567 operate on a <tree> object but automatically dereferences
568 <commit> and <tag> objects that point at a <tree>.
569
570 <commit-ish>::
571 Indicates a commit or tag object name. A
572 command that takes a <commit-ish> argument ultimately wants to
573 operate on a <commit> object but automatically dereferences
574 <tag> objects that point at a <commit>.
575
576 <type>::
577 Indicates that an object type is required.
578 Currently one of: `blob`, `tree`, `commit`, or `tag`.
579
580 <file>::
581 Indicates a filename - almost always relative to the
582 root of the tree structure `GIT_INDEX_FILE` describes.
583
584 Symbolic Identifiers
585 --------------------
586 Any git command accepting any <object> can also use the following
587 symbolic notation:
588
589 HEAD::
590 indicates the head of the current branch.
591
592 <tag>::
593 a valid tag 'name'
594 (i.e. a `refs/tags/<tag>` reference).
595
596 <head>::
597 a valid head 'name'
598 (i.e. a `refs/heads/<head>` reference).
599
600 For a more complete list of ways to spell object names, see
601 "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
602
603
604 File/Directory Structure
605 ------------------------
606
607 Please see the linkgit:gitrepository-layout[5] document.
608
609 Read linkgit:githooks[5] for more details about each hook.
610
611 Higher level SCMs may provide and manage additional information in the
612 `$GIT_DIR`.
613
614
615 Terminology
616 -----------
617 Please see linkgit:gitglossary[7].
618
619
620 Environment Variables
621 ---------------------
622 Various git commands use the following environment variables:
623
624 The git Repository
625 ~~~~~~~~~~~~~~~~~~
626 These environment variables apply to 'all' core git commands. Nb: it
627 is worth noting that they may be used/overridden by SCMS sitting above
628 git so take care if using Cogito etc.
629
630 'GIT_INDEX_FILE'::
631 This environment allows the specification of an alternate
632 index file. If not specified, the default of `$GIT_DIR/index`
633 is used.
634
635 'GIT_OBJECT_DIRECTORY'::
636 If the object storage directory is specified via this
637 environment variable then the sha1 directories are created
638 underneath - otherwise the default `$GIT_DIR/objects`
639 directory is used.
640
641 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
642 Due to the immutable nature of git objects, old objects can be
643 archived into shared, read-only directories. This variable
644 specifies a ":" separated (on Windows ";" separated) list
645 of git object directories which can be used to search for git
646 objects. New objects will not be written to these directories.
647
648 'GIT_DIR'::
649 If the 'GIT_DIR' environment variable is set then it
650 specifies a path to use instead of the default `.git`
651 for the base of the repository.
652
653 'GIT_WORK_TREE'::
654 Set the path to the working tree. The value will not be
655 used in combination with repositories found automatically in
656 a .git directory (i.e. $GIT_DIR is not set).
657 This can also be controlled by the '--work-tree' command line
658 option and the core.worktree configuration variable.
659
660 'GIT_NAMESPACE'::
661 Set the git namespace; see linkgit:gitnamespaces[7] for details.
662 The '--namespace' command-line option also sets this value.
663
664 'GIT_CEILING_DIRECTORIES'::
665 This should be a colon-separated list of absolute paths.
666 If set, it is a list of directories that git should not chdir
667 up into while looking for a repository directory.
668 It will not exclude the current working directory or
669 a GIT_DIR set on the command line or in the environment.
670 (Useful for excluding slow-loading network directories.)
671
672 'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
673 When run in a directory that does not have ".git" repository
674 directory, git tries to find such a directory in the parent
675 directories to find the top of the working tree, but by default it
676 does not cross filesystem boundaries. This environment variable
677 can be set to true to tell git not to stop at filesystem
678 boundaries. Like 'GIT_CEILING_DIRECTORIES', this will not affect
679 an explicit repository directory set via 'GIT_DIR' or on the
680 command line.
681
682 git Commits
683 ~~~~~~~~~~~
684 'GIT_AUTHOR_NAME'::
685 'GIT_AUTHOR_EMAIL'::
686 'GIT_AUTHOR_DATE'::
687 'GIT_COMMITTER_NAME'::
688 'GIT_COMMITTER_EMAIL'::
689 'GIT_COMMITTER_DATE'::
690 'EMAIL'::
691 see linkgit:git-commit-tree[1]
692
693 git Diffs
694 ~~~~~~~~~
695 'GIT_DIFF_OPTS'::
696 Only valid setting is "--unified=??" or "-u??" to set the
697 number of context lines shown when a unified diff is created.
698 This takes precedence over any "-U" or "--unified" option
699 value passed on the git diff command line.
700
701 'GIT_EXTERNAL_DIFF'::
702 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
703 program named by it is called, instead of the diff invocation
704 described above. For a path that is added, removed, or modified,
705 'GIT_EXTERNAL_DIFF' is called with 7 parameters:
706
707 path old-file old-hex old-mode new-file new-hex new-mode
708 +
709 where:
710
711 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
712 contents of <old|new>,
713 <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
714 <old|new>-mode:: are the octal representation of the file modes.
715 +
716 The file parameters can point at the user's working file
717 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
718 when a new file is added), or a temporary file (e.g. `old-file` in the
719 index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
720 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
721 +
722 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
723 parameter, <path>.
724
725 other
726 ~~~~~
727 'GIT_MERGE_VERBOSITY'::
728 A number controlling the amount of output shown by
729 the recursive merge strategy. Overrides merge.verbosity.
730 See linkgit:git-merge[1]
731
732 'GIT_PAGER'::
733 This environment variable overrides `$PAGER`. If it is set
734 to an empty string or to the value "cat", git will not launch
735 a pager. See also the `core.pager` option in
736 linkgit:git-config[1].
737
738 'GIT_EDITOR'::
739 This environment variable overrides `$EDITOR` and `$VISUAL`.
740 It is used by several git commands when, on interactive mode,
741 an editor is to be launched. See also linkgit:git-var[1]
742 and the `core.editor` option in linkgit:git-config[1].
743
744 'GIT_SSH'::
745 If this environment variable is set then 'git fetch'
746 and 'git push' will use this command instead
747 of 'ssh' when they need to connect to a remote system.
748 The '$GIT_SSH' command will be given exactly two arguments:
749 the 'username@host' (or just 'host') from the URL and the
750 shell command to execute on that remote system.
751 +
752 To pass options to the program that you want to list in GIT_SSH
753 you will need to wrap the program and options into a shell script,
754 then set GIT_SSH to refer to the shell script.
755 +
756 Usually it is easier to configure any desired options through your
757 personal `.ssh/config` file. Please consult your ssh documentation
758 for further details.
759
760 'GIT_ASKPASS'::
761 If this environment variable is set, then git commands which need to
762 acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
763 will call this program with a suitable prompt as command line argument
764 and read the password from its STDOUT. See also the 'core.askpass'
765 option in linkgit:git-config[1].
766
767 'GIT_FLUSH'::
768 If this environment variable is set to "1", then commands such
769 as 'git blame' (in incremental mode), 'git rev-list', 'git log',
770 and 'git whatchanged' will force a flush of the output stream
771 after each commit-oriented record have been flushed. If this
772 variable is set to "0", the output of these commands will be done
773 using completely buffered I/O. If this environment variable is
774 not set, git will choose buffered or record-oriented flushing
775 based on whether stdout appears to be redirected to a file or not.
776
777 'GIT_TRACE'::
778 If this variable is set to "1", "2" or "true" (comparison
779 is case insensitive), git will print `trace:` messages on
780 stderr telling about alias expansion, built-in command
781 execution and external command execution.
782 If this variable is set to an integer value greater than 1
783 and lower than 10 (strictly) then git will interpret this
784 value as an open file descriptor and will try to write the
785 trace messages into this file descriptor.
786 Alternatively, if this variable is set to an absolute path
787 (starting with a '/' character), git will interpret this
788 as a file path and will try to write the trace messages
789 into it.
790
791 Discussion[[Discussion]]
792 ------------------------
793
794 More detail on the following is available from the
795 link:user-manual.html#git-concepts[git concepts chapter of the
796 user-manual] and linkgit:gitcore-tutorial[7].
797
798 A git project normally consists of a working directory with a ".git"
799 subdirectory at the top level. The .git directory contains, among other
800 things, a compressed object database representing the complete history
801 of the project, an "index" file which links that history to the current
802 contents of the working tree, and named pointers into that history such
803 as tags and branch heads.
804
805 The object database contains objects of three main types: blobs, which
806 hold file data; trees, which point to blobs and other trees to build up
807 directory hierarchies; and commits, which each reference a single tree
808 and some number of parent commits.
809
810 The commit, equivalent to what other systems call a "changeset" or
811 "version", represents a step in the project's history, and each parent
812 represents an immediately preceding step. Commits with more than one
813 parent represent merges of independent lines of development.
814
815 All objects are named by the SHA1 hash of their contents, normally
816 written as a string of 40 hex digits. Such names are globally unique.
817 The entire history leading up to a commit can be vouched for by signing
818 just that commit. A fourth object type, the tag, is provided for this
819 purpose.
820
821 When first created, objects are stored in individual files, but for
822 efficiency may later be compressed together into "pack files".
823
824 Named pointers called refs mark interesting points in history. A ref
825 may contain the SHA1 name of an object or the name of another ref. Refs
826 with names beginning `ref/head/` contain the SHA1 name of the most
827 recent commit (or "head") of a branch under development. SHA1 names of
828 tags of interest are stored under `ref/tags/`. A special ref named
829 `HEAD` contains the name of the currently checked-out branch.
830
831 The index file is initialized with a list of all paths and, for each
832 path, a blob object and a set of attributes. The blob object represents
833 the contents of the file as of the head of the current branch. The
834 attributes (last modified time, size, etc.) are taken from the
835 corresponding file in the working tree. Subsequent changes to the
836 working tree can be found by comparing these attributes. The index may
837 be updated with new content, and new commits may be created from the
838 content stored in the index.
839
840 The index is also capable of storing multiple entries (called "stages")
841 for a given pathname. These stages are used to hold the various
842 unmerged version of a file when a merge is in progress.
843
844 FURTHER DOCUMENTATION
845 ---------------------
846
847 See the references in the "description" section to get started
848 using git. The following is probably more detail than necessary
849 for a first-time user.
850
851 The link:user-manual.html#git-concepts[git concepts chapter of the
852 user-manual] and linkgit:gitcore-tutorial[7] both provide
853 introductions to the underlying git architecture.
854
855 See linkgit:gitworkflows[7] for an overview of recommended workflows.
856
857 See also the link:howto-index.html[howto] documents for some useful
858 examples.
859
860 The internals are documented in the
861 link:technical/api-index.html[GIT API documentation].
862
863 Users migrating from CVS may also want to
864 read linkgit:gitcvs-migration[7].
865
866
867 Authors
868 -------
869 Git was started by Linus Torvalds, and is currently maintained by Junio
870 C Hamano. Numerous contributions have come from the git mailing list
871 <git@vger.kernel.org>. For a more complete list of contributors, see
872 http://git-scm.com/about. If you have a clone of git.git itself, the
873 output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
874 the authors for specific parts of the project.
875
876 Reporting Bugs
877 --------------
878
879 Report bugs to the Git mailing list <git@vger.kernel.org> where the
880 development and maintenance is primarily done. You do not have to be
881 subscribed to the list to send a message there.
882
883 SEE ALSO
884 --------
885 linkgit:gittutorial[7], linkgit:gittutorial-2[7],
886 link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
887 linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
888 linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
889 linkgit:gitworkflows[7]
890
891 GIT
892 ---
893 Part of the linkgit:git[1] suite