GIT 1.6.0
[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] [--exec-path[=GIT_EXEC_PATH]]
13 [-p|--paginate|--no-pager]
14 [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE]
15 [--help] COMMAND [ARGS]
16
17 DESCRIPTION
18 -----------
19 Git is a fast, scalable, distributed revision control system with an
20 unusually rich command set that provides both high-level operations
21 and full access to internals.
22
23 See linkgit:gittutorial[7] to get started, then see
24 link:everyday.html[Everyday Git] for a useful minimum set of commands, and
25 "man git-commandname" for documentation of each command. CVS users may
26 also want to read linkgit:gitcvs-migration[7]. See
27 the link:user-manual.html[Git User's Manual] for a more in-depth
28 introduction.
29
30 The COMMAND is either a name of a Git command (see below) or an alias
31 as defined in the configuration file (see linkgit:git-config[1]).
32
33 Formatted and hyperlinked version of the latest git
34 documentation can be viewed at
35 `http://www.kernel.org/pub/software/scm/git/docs/`.
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:v1.6.0/git.html[documentation for release 1.6.0]
47
48 * release notes for
49 link:RelNotes-1.6.0.txt[1.6.0].
50
51 * link:v1.5.6.5/git.html[documentation for release 1.5.6.5]
52
53 * release notes for
54 link:RelNotes-1.5.6.5.txt[1.5.6.5],
55 link:RelNotes-1.5.6.4.txt[1.5.6.4],
56 link:RelNotes-1.5.6.3.txt[1.5.6.3],
57 link:RelNotes-1.5.6.2.txt[1.5.6.2],
58 link:RelNotes-1.5.6.1.txt[1.5.6.1],
59 link:RelNotes-1.5.6.txt[1.5.6].
60
61 * link:v1.5.5.4/git.html[documentation for release 1.5.5.4]
62
63 * release notes for
64 link:RelNotes-1.5.5.4.txt[1.5.5.4],
65 link:RelNotes-1.5.5.3.txt[1.5.5.3],
66 link:RelNotes-1.5.5.2.txt[1.5.5.2],
67 link:RelNotes-1.5.5.1.txt[1.5.5.1],
68 link:RelNotes-1.5.5.txt[1.5.5].
69
70 * link:v1.5.4.5/git.html[documentation for release 1.5.4.5]
71
72 * release notes for
73 link:RelNotes-1.5.4.5.txt[1.5.4.5],
74 link:RelNotes-1.5.4.4.txt[1.5.4.4],
75 link:RelNotes-1.5.4.3.txt[1.5.4.3],
76 link:RelNotes-1.5.4.2.txt[1.5.4.2],
77 link:RelNotes-1.5.4.1.txt[1.5.4.1],
78 link:RelNotes-1.5.4.txt[1.5.4].
79
80 * link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
81
82 * release notes for
83 link:RelNotes-1.5.3.8.txt[1.5.3.8],
84 link:RelNotes-1.5.3.7.txt[1.5.3.7],
85 link:RelNotes-1.5.3.6.txt[1.5.3.6],
86 link:RelNotes-1.5.3.5.txt[1.5.3.5],
87 link:RelNotes-1.5.3.4.txt[1.5.3.4],
88 link:RelNotes-1.5.3.3.txt[1.5.3.3],
89 link:RelNotes-1.5.3.2.txt[1.5.3.2],
90 link:RelNotes-1.5.3.1.txt[1.5.3.1],
91 link:RelNotes-1.5.3.txt[1.5.3].
92
93 * link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
94
95 * release notes for
96 link:RelNotes-1.5.2.5.txt[1.5.2.5],
97 link:RelNotes-1.5.2.4.txt[1.5.2.4],
98 link:RelNotes-1.5.2.3.txt[1.5.2.3],
99 link:RelNotes-1.5.2.2.txt[1.5.2.2],
100 link:RelNotes-1.5.2.1.txt[1.5.2.1],
101 link:RelNotes-1.5.2.txt[1.5.2].
102
103 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
104
105 * release notes for
106 link:RelNotes-1.5.1.6.txt[1.5.1.6],
107 link:RelNotes-1.5.1.5.txt[1.5.1.5],
108 link:RelNotes-1.5.1.4.txt[1.5.1.4],
109 link:RelNotes-1.5.1.3.txt[1.5.1.3],
110 link:RelNotes-1.5.1.2.txt[1.5.1.2],
111 link:RelNotes-1.5.1.1.txt[1.5.1.1],
112 link:RelNotes-1.5.1.txt[1.5.1].
113
114 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
115
116 * release notes for
117 link:RelNotes-1.5.0.7.txt[1.5.0.7],
118 link:RelNotes-1.5.0.6.txt[1.5.0.6],
119 link:RelNotes-1.5.0.5.txt[1.5.0.5],
120 link:RelNotes-1.5.0.3.txt[1.5.0.3],
121 link:RelNotes-1.5.0.2.txt[1.5.0.2],
122 link:RelNotes-1.5.0.1.txt[1.5.0.1],
123 link:RelNotes-1.5.0.txt[1.5.0].
124
125 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
126 link:v1.3.3/git.html[1.3.3],
127 link:v1.2.6/git.html[1.2.6],
128 link:v1.0.13/git.html[1.0.13].
129
130 ============
131
132 endif::stalenotes[]
133
134 OPTIONS
135 -------
136 --version::
137 Prints the git suite version that the 'git' program came from.
138
139 --help::
140 Prints the synopsis and a list of the most commonly used
141 commands. If the option '--all' or '-a' is given then all
142 available commands are printed. If a git command is named this
143 option will bring up the manual page for that command.
144 +
145 Other options are available to control how the manual page is
146 displayed. See linkgit:git-help[1] for more information,
147 because `git --help ...` is converted internally into `git
148 help ...`.
149
150 --exec-path::
151 Path to wherever your core git programs are installed.
152 This can also be controlled by setting the GIT_EXEC_PATH
153 environment variable. If no path is given, 'git' will print
154 the current setting and then exit.
155
156 -p::
157 --paginate::
158 Pipe all output into 'less' (or if set, $PAGER).
159
160 --no-pager::
161 Do not pipe git output into a pager.
162
163 --git-dir=<path>::
164 Set the path to the repository. This can also be controlled by
165 setting the GIT_DIR environment variable. It can be an absolute
166 path or relative path to current working directory.
167
168 --work-tree=<path>::
169 Set the path to the working tree. The value will not be
170 used in combination with repositories found automatically in
171 a .git directory (i.e. $GIT_DIR is not set).
172 This can also be controlled by setting the GIT_WORK_TREE
173 environment variable and the core.worktree configuration
174 variable. It can be an absolute path or relative path to
175 the directory specified by --git-dir or GIT_DIR.
176 Note: If --git-dir or GIT_DIR are specified but none of
177 --work-tree, GIT_WORK_TREE and core.worktree is specified,
178 the current working directory is regarded as the top directory
179 of your working tree.
180
181 --bare::
182 Treat the repository as a bare repository. If GIT_DIR
183 environment is not set, it is set to the current working
184 directory.
185
186
187 FURTHER DOCUMENTATION
188 ---------------------
189
190 See the references above to get started using git. The following is
191 probably more detail than necessary for a first-time user.
192
193 The link:user-manual.html#git-concepts[git concepts chapter of the
194 user-manual] and linkgit:gitcore-tutorial[7] both provide
195 introductions to the underlying git architecture.
196
197 See also the link:howto-index.html[howto] documents for some useful
198 examples.
199
200 The internals are documented in the
201 link:technical/api-index.html[GIT API documentation].
202
203 GIT COMMANDS
204 ------------
205
206 We divide git into high level ("porcelain") commands and low level
207 ("plumbing") commands.
208
209 High-level commands (porcelain)
210 -------------------------------
211
212 We separate the porcelain commands into the main commands and some
213 ancillary user utilities.
214
215 Main porcelain commands
216 ~~~~~~~~~~~~~~~~~~~~~~~
217
218 include::cmds-mainporcelain.txt[]
219
220 Ancillary Commands
221 ~~~~~~~~~~~~~~~~~~
222 Manipulators:
223
224 include::cmds-ancillarymanipulators.txt[]
225
226 Interrogators:
227
228 include::cmds-ancillaryinterrogators.txt[]
229
230
231 Interacting with Others
232 ~~~~~~~~~~~~~~~~~~~~~~~
233
234 These commands are to interact with foreign SCM and with other
235 people via patch over e-mail.
236
237 include::cmds-foreignscminterface.txt[]
238
239
240 Low-level commands (plumbing)
241 -----------------------------
242
243 Although git includes its
244 own porcelain layer, its low-level commands are sufficient to support
245 development of alternative porcelains. Developers of such porcelains
246 might start by reading about linkgit:git-update-index[1] and
247 linkgit:git-read-tree[1].
248
249 The interface (input, output, set of options and the semantics)
250 to these low-level commands are meant to be a lot more stable
251 than Porcelain level commands, because these commands are
252 primarily for scripted use. The interface to Porcelain commands
253 on the other hand are subject to change in order to improve the
254 end user experience.
255
256 The following description divides
257 the low-level commands into commands that manipulate objects (in
258 the repository, index, and working tree), commands that interrogate and
259 compare objects, and commands that move objects and references between
260 repositories.
261
262
263 Manipulation commands
264 ~~~~~~~~~~~~~~~~~~~~~
265
266 include::cmds-plumbingmanipulators.txt[]
267
268
269 Interrogation commands
270 ~~~~~~~~~~~~~~~~~~~~~~
271
272 include::cmds-plumbinginterrogators.txt[]
273
274 In general, the interrogate commands do not touch the files in
275 the working tree.
276
277
278 Synching repositories
279 ~~~~~~~~~~~~~~~~~~~~~
280
281 include::cmds-synchingrepositories.txt[]
282
283 The following are helper programs used by the above; end users
284 typically do not use them directly.
285
286 include::cmds-synchelpers.txt[]
287
288
289 Internal helper commands
290 ~~~~~~~~~~~~~~~~~~~~~~~~
291
292 These are internal helper commands used by other commands; end
293 users typically do not use them directly.
294
295 include::cmds-purehelpers.txt[]
296
297
298 Configuration Mechanism
299 -----------------------
300
301 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
302 is used to hold per-repository configuration options. It is a
303 simple text file modeled after `.ini` format familiar to some
304 people. Here is an example:
305
306 ------------
307 #
308 # A '#' or ';' character indicates a comment.
309 #
310
311 ; core variables
312 [core]
313 ; Don't trust file modes
314 filemode = false
315
316 ; user identity
317 [user]
318 name = "Junio C Hamano"
319 email = "junkio@twinsun.com"
320
321 ------------
322
323 Various commands read from the configuration file and adjust
324 their operation accordingly.
325
326
327 Identifier Terminology
328 ----------------------
329 <object>::
330 Indicates the object name for any type of object.
331
332 <blob>::
333 Indicates a blob object name.
334
335 <tree>::
336 Indicates a tree object name.
337
338 <commit>::
339 Indicates a commit object name.
340
341 <tree-ish>::
342 Indicates a tree, commit or tag object name. A
343 command that takes a <tree-ish> argument ultimately wants to
344 operate on a <tree> object but automatically dereferences
345 <commit> and <tag> objects that point at a <tree>.
346
347 <commit-ish>::
348 Indicates a commit or tag object name. A
349 command that takes a <commit-ish> argument ultimately wants to
350 operate on a <commit> object but automatically dereferences
351 <tag> objects that point at a <commit>.
352
353 <type>::
354 Indicates that an object type is required.
355 Currently one of: `blob`, `tree`, `commit`, or `tag`.
356
357 <file>::
358 Indicates a filename - almost always relative to the
359 root of the tree structure `GIT_INDEX_FILE` describes.
360
361 Symbolic Identifiers
362 --------------------
363 Any git command accepting any <object> can also use the following
364 symbolic notation:
365
366 HEAD::
367 indicates the head of the current branch (i.e. the
368 contents of `$GIT_DIR/HEAD`).
369
370 <tag>::
371 a valid tag 'name'
372 (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`).
373
374 <head>::
375 a valid head 'name'
376 (i.e. the contents of `$GIT_DIR/refs/heads/<head>`).
377
378 For a more complete list of ways to spell object names, see
379 "SPECIFYING REVISIONS" section in linkgit:git-rev-parse[1].
380
381
382 File/Directory Structure
383 ------------------------
384
385 Please see the linkgit:gitrepository-layout[5] document.
386
387 Read linkgit:githooks[5] for more details about each hook.
388
389 Higher level SCMs may provide and manage additional information in the
390 `$GIT_DIR`.
391
392
393 Terminology
394 -----------
395 Please see linkgit:gitglossary[7].
396
397
398 Environment Variables
399 ---------------------
400 Various git commands use the following environment variables:
401
402 The git Repository
403 ~~~~~~~~~~~~~~~~~~
404 These environment variables apply to 'all' core git commands. Nb: it
405 is worth noting that they may be used/overridden by SCMS sitting above
406 git so take care if using Cogito etc.
407
408 'GIT_INDEX_FILE'::
409 This environment allows the specification of an alternate
410 index file. If not specified, the default of `$GIT_DIR/index`
411 is used.
412
413 'GIT_OBJECT_DIRECTORY'::
414 If the object storage directory is specified via this
415 environment variable then the sha1 directories are created
416 underneath - otherwise the default `$GIT_DIR/objects`
417 directory is used.
418
419 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
420 Due to the immutable nature of git objects, old objects can be
421 archived into shared, read-only directories. This variable
422 specifies a ":" separated (on Windows ";" separated) list
423 of git object directories which can be used to search for git
424 objects. New objects will not be written to these directories.
425
426 'GIT_DIR'::
427 If the 'GIT_DIR' environment variable is set then it
428 specifies a path to use instead of the default `.git`
429 for the base of the repository.
430
431 'GIT_WORK_TREE'::
432 Set the path to the working tree. The value will not be
433 used in combination with repositories found automatically in
434 a .git directory (i.e. $GIT_DIR is not set).
435 This can also be controlled by the '--work-tree' command line
436 option and the core.worktree configuration variable.
437
438 'GIT_CEILING_DIRECTORIES'::
439 This should be a colon-separated list of absolute paths.
440 If set, it is a list of directories that git should not chdir
441 up into while looking for a repository directory.
442 It will not exclude the current working directory or
443 a GIT_DIR set on the command line or in the environment.
444 (Useful for excluding slow-loading network directories.)
445
446 git Commits
447 ~~~~~~~~~~~
448 'GIT_AUTHOR_NAME'::
449 'GIT_AUTHOR_EMAIL'::
450 'GIT_AUTHOR_DATE'::
451 'GIT_COMMITTER_NAME'::
452 'GIT_COMMITTER_EMAIL'::
453 'GIT_COMMITTER_DATE'::
454 'EMAIL'::
455 see linkgit:git-commit-tree[1]
456
457 git Diffs
458 ~~~~~~~~~
459 'GIT_DIFF_OPTS'::
460 Only valid setting is "--unified=??" or "-u??" to set the
461 number of context lines shown when a unified diff is created.
462 This takes precedence over any "-U" or "--unified" option
463 value passed on the git diff command line.
464
465 'GIT_EXTERNAL_DIFF'::
466 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
467 program named by it is called, instead of the diff invocation
468 described above. For a path that is added, removed, or modified,
469 'GIT_EXTERNAL_DIFF' is called with 7 parameters:
470
471 path old-file old-hex old-mode new-file new-hex new-mode
472 +
473 where:
474
475 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
476 contents of <old|new>,
477 <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
478 <old|new>-mode:: are the octal representation of the file modes.
479
480 +
481 The file parameters can point at the user's working file
482 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
483 when a new file is added), or a temporary file (e.g. `old-file` in the
484 index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
485 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
486 +
487 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
488 parameter, <path>.
489
490 other
491 ~~~~~
492 'GIT_MERGE_VERBOSITY'::
493 A number controlling the amount of output shown by
494 the recursive merge strategy. Overrides merge.verbosity.
495 See linkgit:git-merge[1]
496
497 'GIT_PAGER'::
498 This environment variable overrides `$PAGER`. If it is set
499 to an empty string or to the value "cat", git will not launch
500 a pager.
501
502 'GIT_SSH'::
503 If this environment variable is set then 'git-fetch'
504 and 'git-push' will use this command instead
505 of 'ssh' when they need to connect to a remote system.
506 The '$GIT_SSH' command will be given exactly two arguments:
507 the 'username@host' (or just 'host') from the URL and the
508 shell command to execute on that remote system.
509 +
510 To pass options to the program that you want to list in GIT_SSH
511 you will need to wrap the program and options into a shell script,
512 then set GIT_SSH to refer to the shell script.
513 +
514 Usually it is easier to configure any desired options through your
515 personal `.ssh/config` file. Please consult your ssh documentation
516 for further details.
517
518 'GIT_FLUSH'::
519 If this environment variable is set to "1", then commands such
520 as 'git-blame' (in incremental mode), 'git-rev-list', 'git-log',
521 and 'git-whatchanged' will force a flush of the output stream
522 after each commit-oriented record have been flushed. If this
523 variable is set to "0", the output of these commands will be done
524 using completely buffered I/O. If this environment variable is
525 not set, git will choose buffered or record-oriented flushing
526 based on whether stdout appears to be redirected to a file or not.
527
528 'GIT_TRACE'::
529 If this variable is set to "1", "2" or "true" (comparison
530 is case insensitive), git will print `trace:` messages on
531 stderr telling about alias expansion, built-in command
532 execution and external command execution.
533 If this variable is set to an integer value greater than 1
534 and lower than 10 (strictly) then git will interpret this
535 value as an open file descriptor and will try to write the
536 trace messages into this file descriptor.
537 Alternatively, if this variable is set to an absolute path
538 (starting with a '/' character), git will interpret this
539 as a file path and will try to write the trace messages
540 into it.
541
542 Discussion[[Discussion]]
543 ------------------------
544
545 More detail on the following is available from the
546 link:user-manual.html#git-concepts[git concepts chapter of the
547 user-manual] and linkgit:gitcore-tutorial[7].
548
549 A git project normally consists of a working directory with a ".git"
550 subdirectory at the top level. The .git directory contains, among other
551 things, a compressed object database representing the complete history
552 of the project, an "index" file which links that history to the current
553 contents of the working tree, and named pointers into that history such
554 as tags and branch heads.
555
556 The object database contains objects of three main types: blobs, which
557 hold file data; trees, which point to blobs and other trees to build up
558 directory hierarchies; and commits, which each reference a single tree
559 and some number of parent commits.
560
561 The commit, equivalent to what other systems call a "changeset" or
562 "version", represents a step in the project's history, and each parent
563 represents an immediately preceding step. Commits with more than one
564 parent represent merges of independent lines of development.
565
566 All objects are named by the SHA1 hash of their contents, normally
567 written as a string of 40 hex digits. Such names are globally unique.
568 The entire history leading up to a commit can be vouched for by signing
569 just that commit. A fourth object type, the tag, is provided for this
570 purpose.
571
572 When first created, objects are stored in individual files, but for
573 efficiency may later be compressed together into "pack files".
574
575 Named pointers called refs mark interesting points in history. A ref
576 may contain the SHA1 name of an object or the name of another ref. Refs
577 with names beginning `ref/head/` contain the SHA1 name of the most
578 recent commit (or "head") of a branch under development. SHA1 names of
579 tags of interest are stored under `ref/tags/`. A special ref named
580 `HEAD` contains the name of the currently checked-out branch.
581
582 The index file is initialized with a list of all paths and, for each
583 path, a blob object and a set of attributes. The blob object represents
584 the contents of the file as of the head of the current branch. The
585 attributes (last modified time, size, etc.) are taken from the
586 corresponding file in the working tree. Subsequent changes to the
587 working tree can be found by comparing these attributes. The index may
588 be updated with new content, and new commits may be created from the
589 content stored in the index.
590
591 The index is also capable of storing multiple entries (called "stages")
592 for a given pathname. These stages are used to hold the various
593 unmerged version of a file when a merge is in progress.
594
595 Authors
596 -------
597 * git's founding father is Linus Torvalds <torvalds@osdl.org>.
598 * The current git nurse is Junio C Hamano <gitster@pobox.com>.
599 * The git potty was written by Andreas Ericsson <ae@op5.se>.
600 * General upbringing is handled by the git-list <git@vger.kernel.org>.
601
602 Documentation
603 --------------
604 The documentation for git suite was started by David Greaves
605 <david@dgreaves.com>, and later enhanced greatly by the
606 contributors on the git-list <git@vger.kernel.org>.
607
608 SEE ALSO
609 --------
610 linkgit:gittutorial[7], linkgit:gittutorial-2[7],
611 link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
612 linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
613 linkgit:gitcli[7], link:user-manual.html[The Git User's Manual]
614
615 GIT
616 ---
617 Part of the linkgit:git[1] suite