Merge branch 'maint'
[git/git.git] / Documentation / git.txt
1 git(7)
2 ======
3
4 NAME
5 ----
6 git - the stupid content tracker
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git' [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate]
13 [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE]
14 [--help] COMMAND [ARGS]
15
16 DESCRIPTION
17 -----------
18 Git is a fast, scalable, distributed revision control system with an
19 unusually rich command set that provides both high-level operations
20 and full access to internals.
21
22 See this link:tutorial.html[tutorial] to get started, then see
23 link:everyday.html[Everyday Git] for a useful minimum set of commands, and
24 "man git-commandname" for documentation of each command. CVS users may
25 also want to read link:cvs-migration.html[CVS migration]. See
26 link:user-manual.html[Git User's Manual] for a more in-depth
27 introduction.
28
29 The COMMAND is either a name of a Git command (see below) or an alias
30 as defined in the configuration file (see gitlink:git-config[1]).
31
32 Formatted and hyperlinked version of the latest git
33 documentation can be viewed at
34 `http://www.kernel.org/pub/software/scm/git/docs/`.
35
36 ifdef::stalenotes[]
37 [NOTE]
38 ============
39
40 You are reading the documentation for the latest (possibly
41 unreleased) version of git, that is available from 'master'
42 branch of the `git.git` repository.
43 Documentation for older releases are available here:
44
45 * link:v1.5.2.3/git.html[documentation for release 1.5.2.3]
46
47 * release notes for
48 link:RelNotes-1.5.2.3.txt[1.5.2.3],
49 link:RelNotes-1.5.2.2.txt[1.5.2.2],
50 link:RelNotes-1.5.2.1.txt[1.5.2.1],
51 link:RelNotes-1.5.2.txt[1.5.2].
52
53 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
54
55 * release notes for
56 link:RelNotes-1.5.1.6.txt[1.5.1.6],
57 link:RelNotes-1.5.1.5.txt[1.5.1.5],
58 link:RelNotes-1.5.1.4.txt[1.5.1.4],
59 link:RelNotes-1.5.1.3.txt[1.5.1.3],
60 link:RelNotes-1.5.1.2.txt[1.5.1.2],
61 link:RelNotes-1.5.1.1.txt[1.5.1.1],
62 link:RelNotes-1.5.1.txt[1.5.1].
63
64 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
65
66 * release notes for
67 link:RelNotes-1.5.0.7.txt[1.5.0.7],
68 link:RelNotes-1.5.0.6.txt[1.5.0.6],
69 link:RelNotes-1.5.0.5.txt[1.5.0.5],
70 link:RelNotes-1.5.0.3.txt[1.5.0.3],
71 link:RelNotes-1.5.0.2.txt[1.5.0.2],
72 link:RelNotes-1.5.0.1.txt[1.5.0.1],
73 link:RelNotes-1.5.0.txt[1.5.0].
74
75 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
76 link:v1.3.3/git.html[1.3.3],
77 link:v1.2.6/git.html[1.2.6],
78 link:v1.0.13/git.html[1.0.13].
79
80 ============
81
82 endif::stalenotes[]
83
84 OPTIONS
85 -------
86 --version::
87 Prints the git suite version that the 'git' program came from.
88
89 --help::
90 Prints the synopsis and a list of the most commonly used
91 commands. If a git command is named this option will bring up
92 the man-page for that command. If the option '--all' or '-a' is
93 given then all available commands are printed.
94
95 --exec-path::
96 Path to wherever your core git programs are installed.
97 This can also be controlled by setting the GIT_EXEC_PATH
98 environment variable. If no path is given 'git' will print
99 the current setting and then exit.
100
101 -p|--paginate::
102 Pipe all output into 'less' (or if set, $PAGER).
103
104 --git-dir=<path>::
105 Set the path to the repository. This can also be controlled by
106 setting the GIT_DIR environment variable.
107
108 --work-tree=<path>::
109 Set the path to the working tree. The value will not be
110 used in combination with repositories found automatically in
111 a .git directory (i.e. $GIT_DIR is not set).
112 This can also be controlled by setting the GIT_WORK_TREE
113 environment variable and the core.worktree configuration
114 variable.
115
116 --bare::
117 Same as --git-dir=`pwd`.
118
119 FURTHER DOCUMENTATION
120 ---------------------
121
122 See the references above to get started using git. The following is
123 probably more detail than necessary for a first-time user.
124
125 The <<Discussion,Discussion>> section below and the
126 link:core-tutorial.html[Core tutorial] both provide introductions to the
127 underlying git architecture.
128
129 See also the link:howto-index.html[howto] documents for some useful
130 examples.
131
132 GIT COMMANDS
133 ------------
134
135 We divide git into high level ("porcelain") commands and low level
136 ("plumbing") commands.
137
138 High-level commands (porcelain)
139 -------------------------------
140
141 We separate the porcelain commands into the main commands and some
142 ancillary user utilities.
143
144 Main porcelain commands
145 ~~~~~~~~~~~~~~~~~~~~~~~
146
147 include::cmds-mainporcelain.txt[]
148
149 Ancillary Commands
150 ~~~~~~~~~~~~~~~~~~
151 Manipulators:
152
153 include::cmds-ancillarymanipulators.txt[]
154
155 Interrogators:
156
157 include::cmds-ancillaryinterrogators.txt[]
158
159
160 Interacting with Others
161 ~~~~~~~~~~~~~~~~~~~~~~~
162
163 These commands are to interact with foreign SCM and with other
164 people via patch over e-mail.
165
166 include::cmds-foreignscminterface.txt[]
167
168
169 Low-level commands (plumbing)
170 -----------------------------
171
172 Although git includes its
173 own porcelain layer, its low-level commands are sufficient to support
174 development of alternative porcelains. Developers of such porcelains
175 might start by reading about gitlink:git-update-index[1] and
176 gitlink:git-read-tree[1].
177
178 The interface (input, output, set of options and the semantics)
179 to these low-level commands are meant to be a lot more stable
180 than Porcelain level commands, because these commands are
181 primarily for scripted use. The interface to Porcelain commands
182 on the other hand are subject to change in order to improve the
183 end user experience.
184
185 The following description divides
186 the low-level commands into commands that manipulate objects (in
187 the repository, index, and working tree), commands that interrogate and
188 compare objects, and commands that move objects and references between
189 repositories.
190
191
192 Manipulation commands
193 ~~~~~~~~~~~~~~~~~~~~~
194
195 include::cmds-plumbingmanipulators.txt[]
196
197
198 Interrogation commands
199 ~~~~~~~~~~~~~~~~~~~~~~
200
201 include::cmds-plumbinginterrogators.txt[]
202
203 In general, the interrogate commands do not touch the files in
204 the working tree.
205
206
207 Synching repositories
208 ~~~~~~~~~~~~~~~~~~~~~
209
210 include::cmds-synchingrepositories.txt[]
211
212 The following are helper programs used by the above; end users
213 typically do not use them directly.
214
215 include::cmds-synchelpers.txt[]
216
217
218 Internal helper commands
219 ~~~~~~~~~~~~~~~~~~~~~~~~
220
221 These are internal helper commands used by other commands; end
222 users typically do not use them directly.
223
224 include::cmds-purehelpers.txt[]
225
226
227 Configuration Mechanism
228 -----------------------
229
230 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
231 is used to hold per-repository configuration options. It is a
232 simple text file modeled after `.ini` format familiar to some
233 people. Here is an example:
234
235 ------------
236 #
237 # A '#' or ';' character indicates a comment.
238 #
239
240 ; core variables
241 [core]
242 ; Don't trust file modes
243 filemode = false
244
245 ; user identity
246 [user]
247 name = "Junio C Hamano"
248 email = "junkio@twinsun.com"
249
250 ------------
251
252 Various commands read from the configuration file and adjust
253 their operation accordingly.
254
255
256 Identifier Terminology
257 ----------------------
258 <object>::
259 Indicates the object name for any type of object.
260
261 <blob>::
262 Indicates a blob object name.
263
264 <tree>::
265 Indicates a tree object name.
266
267 <commit>::
268 Indicates a commit object name.
269
270 <tree-ish>::
271 Indicates a tree, commit or tag object name. A
272 command that takes a <tree-ish> argument ultimately wants to
273 operate on a <tree> object but automatically dereferences
274 <commit> and <tag> objects that point at a <tree>.
275
276 <commit-ish>::
277 Indicates a commit or tag object name. A
278 command that takes a <commit-ish> argument ultimately wants to
279 operate on a <commit> object but automatically dereferences
280 <tag> objects that point at a <commit>.
281
282 <type>::
283 Indicates that an object type is required.
284 Currently one of: `blob`, `tree`, `commit`, or `tag`.
285
286 <file>::
287 Indicates a filename - almost always relative to the
288 root of the tree structure `GIT_INDEX_FILE` describes.
289
290 Symbolic Identifiers
291 --------------------
292 Any git command accepting any <object> can also use the following
293 symbolic notation:
294
295 HEAD::
296 indicates the head of the current branch (i.e. the
297 contents of `$GIT_DIR/HEAD`).
298
299 <tag>::
300 a valid tag 'name'
301 (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`).
302
303 <head>::
304 a valid head 'name'
305 (i.e. the contents of `$GIT_DIR/refs/heads/<head>`).
306
307 For a more complete list of ways to spell object names, see
308 "SPECIFYING REVISIONS" section in gitlink:git-rev-parse[1].
309
310
311 File/Directory Structure
312 ------------------------
313
314 Please see link:repository-layout.html[repository layout] document.
315
316 Read link:hooks.html[hooks] for more details about each hook.
317
318 Higher level SCMs may provide and manage additional information in the
319 `$GIT_DIR`.
320
321
322 Terminology
323 -----------
324 Please see link:glossary.html[glossary] document.
325
326
327 Environment Variables
328 ---------------------
329 Various git commands use the following environment variables:
330
331 The git Repository
332 ~~~~~~~~~~~~~~~~~~
333 These environment variables apply to 'all' core git commands. Nb: it
334 is worth noting that they may be used/overridden by SCMS sitting above
335 git so take care if using Cogito etc.
336
337 'GIT_INDEX_FILE'::
338 This environment allows the specification of an alternate
339 index file. If not specified, the default of `$GIT_DIR/index`
340 is used.
341
342 'GIT_OBJECT_DIRECTORY'::
343 If the object storage directory is specified via this
344 environment variable then the sha1 directories are created
345 underneath - otherwise the default `$GIT_DIR/objects`
346 directory is used.
347
348 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
349 Due to the immutable nature of git objects, old objects can be
350 archived into shared, read-only directories. This variable
351 specifies a ":" separated list of git object directories which
352 can be used to search for git objects. New objects will not be
353 written to these directories.
354
355 'GIT_DIR'::
356 If the 'GIT_DIR' environment variable is set then it
357 specifies a path to use instead of the default `.git`
358 for the base of the repository.
359
360 'GIT_WORK_TREE'::
361 Set the path to the working tree. The value will not be
362 used in combination with repositories found automatically in
363 a .git directory (i.e. $GIT_DIR is not set).
364 This can also be controlled by the '--work-tree' command line
365 option and the core.worktree configuration variable.
366
367 git Commits
368 ~~~~~~~~~~~
369 'GIT_AUTHOR_NAME'::
370 'GIT_AUTHOR_EMAIL'::
371 'GIT_AUTHOR_DATE'::
372 'GIT_COMMITTER_NAME'::
373 'GIT_COMMITTER_EMAIL'::
374 'GIT_COMMITTER_DATE'::
375 'EMAIL'::
376 see gitlink:git-commit-tree[1]
377
378 git Diffs
379 ~~~~~~~~~
380 'GIT_DIFF_OPTS'::
381 Only valid setting is "--unified=??" or "-u??" to set the
382 number of context lines shown when a unified diff is created.
383 This takes precedence over any "-U" or "--unified" option
384 value passed on the git diff command line.
385
386 'GIT_EXTERNAL_DIFF'::
387 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
388 program named by it is called, instead of the diff invocation
389 described above. For a path that is added, removed, or modified,
390 'GIT_EXTERNAL_DIFF' is called with 7 parameters:
391
392 path old-file old-hex old-mode new-file new-hex new-mode
393 +
394 where:
395
396 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
397 contents of <old|new>,
398 <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
399 <old|new>-mode:: are the octal representation of the file modes.
400
401 +
402 The file parameters can point at the user's working file
403 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
404 when a new file is added), or a temporary file (e.g. `old-file` in the
405 index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
406 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
407 +
408 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
409 parameter, <path>.
410
411 other
412 ~~~~~
413 'GIT_PAGER'::
414 This environment variable overrides `$PAGER`.
415
416 'GIT_FLUSH'::
417 If this environment variable is set to "1", then commands such
418 as git-blame (in incremental mode), git-rev-list, git-log,
419 git-whatchanged, etc., will force a flush of the output stream
420 after each commit-oriented record have been flushed. If this
421 variable is set to "0", the output of these commands will be done
422 using completely buffered I/O. If this environment variable is
423 not set, git will choose buffered or record-oriented flushing
424 based on whether stdout appears to be redirected to a file or not.
425
426 'GIT_TRACE'::
427 If this variable is set to "1", "2" or "true" (comparison
428 is case insensitive), git will print `trace:` messages on
429 stderr telling about alias expansion, built-in command
430 execution and external command execution.
431 If this variable is set to an integer value greater than 1
432 and lower than 10 (strictly) then git will interpret this
433 value as an open file descriptor and will try to write the
434 trace messages into this file descriptor.
435 Alternatively, if this variable is set to an absolute path
436 (starting with a '/' character), git will interpret this
437 as a file path and will try to write the trace messages
438 into it.
439
440 Discussion[[Discussion]]
441 ------------------------
442 include::core-intro.txt[]
443
444 Authors
445 -------
446 * git's founding father is Linus Torvalds <torvalds@osdl.org>.
447 * The current git nurse is Junio C Hamano <junkio@cox.net>.
448 * The git potty was written by Andres Ericsson <ae@op5.se>.
449 * General upbringing is handled by the git-list <git@vger.kernel.org>.
450
451 Documentation
452 --------------
453 The documentation for git suite was started by David Greaves
454 <david@dgreaves.com>, and later enhanced greatly by the
455 contributors on the git-list <git@vger.kernel.org>.
456
457 GIT
458 ---
459 Part of the gitlink:git[7] suite