]> git.ipfire.org Git - thirdparty/git.git/blame - Documentation/git.txt
Documentation/git.txt: GIT 1.6.2.2 has been out for a while
[thirdparty/git.git] / Documentation / git.txt
CommitLineData
9e1f0a85 1git(1)
2cf565c5 2======
2cf565c5
DG
3
4NAME
5----
6git - the stupid content tracker
7
8
9SYNOPSIS
10--------
8b70004b 11[verse]
89a56bfb 12'git' [--version] [--exec-path[=GIT_EXEC_PATH]] [--html-path]
463a849d 13 [-p|--paginate|--no-pager]
892c41b9
ML
14 [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE]
15 [--help] COMMAND [ARGS]
2cf565c5
DG
16
17DESCRIPTION
18-----------
23091e95
BF
19Git is a fast, scalable, distributed revision control system with an
20unusually rich command set that provides both high-level operations
21and full access to internals.
22
6998e4db 23See linkgit:gittutorial[7] to get started, then see
23091e95
BF
24link:everyday.html[Everyday Git] for a useful minimum set of commands, and
25"man git-commandname" for documentation of each command. CVS users may
6998e4db
JN
26also want to read linkgit:gitcvs-migration[7]. See
27the link:user-manual.html[Git User's Manual] for a more in-depth
a1dc34fa 28introduction.
cb22bc44 29
4514ad4f 30The COMMAND is either a name of a Git command (see below) or an alias
5162e697 31as defined in the configuration file (see linkgit:git-config[1]).
4514ad4f 32
34b604af
JA
33Formatted and hyperlinked version of the latest git
34documentation can be viewed at
35`http://www.kernel.org/pub/software/scm/git/docs/`.
36
26cfcfbf
JH
37ifdef::stalenotes[]
38[NOTE]
39============
26cfcfbf 40
2ff3f61a
JH
41You are reading the documentation for the latest (possibly
42unreleased) version of git, that is available from 'master'
43branch of the `git.git` repository.
44Documentation for older releases are available here:
43a8e4fe 45
54a47493 46* link:v1.6.2.2/git.html[documentation for release 1.6.2.2]
a95148de
JH
47
48* release notes for
54a47493 49 link:RelNotes-1.6.2.2.txt[1.6.2.2],
de769780 50 link:RelNotes-1.6.2.1.txt[1.6.2.1],
a95148de
JH
51 link:RelNotes-1.6.2.txt[1.6.2].
52
621f1b4b 53* link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
8104ebfe
JH
54
55* release notes for
621f1b4b
JH
56 link:RelNotes-1.6.1.3.txt[1.6.1.3],
57 link:RelNotes-1.6.1.2.txt[1.6.1.2],
c42b1ad9 58 link:RelNotes-1.6.1.1.txt[1.6.1.1],
8104ebfe
JH
59 link:RelNotes-1.6.1.txt[1.6.1].
60
efe05b01 61* link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
ea02eef0
JH
62
63* release notes for
efe05b01 64 link:RelNotes-1.6.0.6.txt[1.6.0.6],
f371d3ea 65 link:RelNotes-1.6.0.5.txt[1.6.0.5],
171d7661
JH
66 link:RelNotes-1.6.0.4.txt[1.6.0.4],
67 link:RelNotes-1.6.0.3.txt[1.6.0.3],
97a7a82f
JH
68 link:RelNotes-1.6.0.2.txt[1.6.0.2],
69 link:RelNotes-1.6.0.1.txt[1.6.0.1],
ea02eef0
JH
70 link:RelNotes-1.6.0.txt[1.6.0].
71
efe05b01 72* link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
e449f105
JH
73
74* release notes for
efe05b01 75 link:RelNotes-1.5.6.6.txt[1.5.6.6],
781c1834 76 link:RelNotes-1.5.6.5.txt[1.5.6.5],
09651dd8
JH
77 link:RelNotes-1.5.6.4.txt[1.5.6.4],
78 link:RelNotes-1.5.6.3.txt[1.5.6.3],
79 link:RelNotes-1.5.6.2.txt[1.5.6.2],
80 link:RelNotes-1.5.6.1.txt[1.5.6.1],
e636106c 81 link:RelNotes-1.5.6.txt[1.5.6].
e449f105 82
efe05b01 83* link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
1d2375dd
JH
84
85* release notes for
efe05b01
JH
86 link:RelNotes-1.5.5.6.txt[1.5.5.6],
87 link:RelNotes-1.5.5.5.txt[1.5.5.5],
7064ca51 88 link:RelNotes-1.5.5.4.txt[1.5.5.4],
28bc3022 89 link:RelNotes-1.5.5.3.txt[1.5.5.3],
2d3922dc 90 link:RelNotes-1.5.5.2.txt[1.5.5.2],
66aaa2fc 91 link:RelNotes-1.5.5.1.txt[1.5.5.1],
1d2375dd
JH
92 link:RelNotes-1.5.5.txt[1.5.5].
93
efe05b01 94* link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
6ce8e44a
JH
95
96* release notes for
efe05b01
JH
97 link:RelNotes-1.5.4.7.txt[1.5.4.7],
98 link:RelNotes-1.5.4.6.txt[1.5.4.6],
803d5158 99 link:RelNotes-1.5.4.5.txt[1.5.4.5],
ad416ed4 100 link:RelNotes-1.5.4.4.txt[1.5.4.4],
923d44ae 101 link:RelNotes-1.5.4.3.txt[1.5.4.3],
cf5c51ef 102 link:RelNotes-1.5.4.2.txt[1.5.4.2],
ecb879f8 103 link:RelNotes-1.5.4.1.txt[1.5.4.1],
6ce8e44a
JH
104 link:RelNotes-1.5.4.txt[1.5.4].
105
e708af6e 106* link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
5587cac2
JH
107
108* release notes for
e708af6e 109 link:RelNotes-1.5.3.8.txt[1.5.3.8],
b52e985a 110 link:RelNotes-1.5.3.7.txt[1.5.3.7],
4a44b9ea 111 link:RelNotes-1.5.3.6.txt[1.5.3.6],
afc05f9f 112 link:RelNotes-1.5.3.5.txt[1.5.3.5],
58ba4f6a 113 link:RelNotes-1.5.3.4.txt[1.5.3.4],
326df26d 114 link:RelNotes-1.5.3.3.txt[1.5.3.3],
077d6f72 115 link:RelNotes-1.5.3.2.txt[1.5.3.2],
8d863c98
JH
116 link:RelNotes-1.5.3.1.txt[1.5.3.1],
117 link:RelNotes-1.5.3.txt[1.5.3].
b6e4db6a 118
e636106c
JH
119* link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
120
aba170cd 121* release notes for
da899deb 122 link:RelNotes-1.5.2.5.txt[1.5.2.5],
baafd6e7 123 link:RelNotes-1.5.2.4.txt[1.5.2.4],
444649e5 124 link:RelNotes-1.5.2.3.txt[1.5.2.3],
3e48af38
JH
125 link:RelNotes-1.5.2.2.txt[1.5.2.2],
126 link:RelNotes-1.5.2.1.txt[1.5.2.1],
aba170cd
JH
127 link:RelNotes-1.5.2.txt[1.5.2].
128
129* link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
130
131* release notes for
132 link:RelNotes-1.5.1.6.txt[1.5.1.6],
133 link:RelNotes-1.5.1.5.txt[1.5.1.5],
2ff3f61a
JH
134 link:RelNotes-1.5.1.4.txt[1.5.1.4],
135 link:RelNotes-1.5.1.3.txt[1.5.1.3],
136 link:RelNotes-1.5.1.2.txt[1.5.1.2],
137 link:RelNotes-1.5.1.1.txt[1.5.1.1],
138 link:RelNotes-1.5.1.txt[1.5.1].
139
140* link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
141
aba170cd
JH
142* release notes for
143 link:RelNotes-1.5.0.7.txt[1.5.0.7],
2ff3f61a
JH
144 link:RelNotes-1.5.0.6.txt[1.5.0.6],
145 link:RelNotes-1.5.0.5.txt[1.5.0.5],
146 link:RelNotes-1.5.0.3.txt[1.5.0.3],
147 link:RelNotes-1.5.0.2.txt[1.5.0.2],
148 link:RelNotes-1.5.0.1.txt[1.5.0.1],
149 link:RelNotes-1.5.0.txt[1.5.0].
150
151* documentation for release link:v1.4.4.4/git.html[1.4.4.4],
152 link:v1.3.3/git.html[1.3.3],
153 link:v1.2.6/git.html[1.2.6],
154 link:v1.0.13/git.html[1.0.13].
26cfcfbf
JH
155
156============
157
158endif::stalenotes[]
159
cb22bc44
AE
160OPTIONS
161-------
162--version::
a87cd02c 163 Prints the git suite version that the 'git' program came from.
cb22bc44
AE
164
165--help::
a87cd02c 166 Prints the synopsis and a list of the most commonly used
0f6f195b
CC
167 commands. If the option '--all' or '-a' is given then all
168 available commands are printed. If a git command is named this
169 option will bring up the manual page for that command.
45533d26
CC
170+
171Other options are available to control how the manual page is
5162e697 172displayed. See linkgit:git-help[1] for more information,
db5d6666
JN
173because `git --help ...` is converted internally into `git
174help ...`.
cb22bc44
AE
175
176--exec-path::
a87cd02c 177 Path to wherever your core git programs are installed.
cb22bc44 178 This can also be controlled by setting the GIT_EXEC_PATH
56992f76 179 environment variable. If no path is given, 'git' will print
cb22bc44
AE
180 the current setting and then exit.
181
89a56bfb
MH
182--html-path::
183 Print the path to wherever your git HTML documentation is installed
184 and exit.
185
3240240f
SB
186-p::
187--paginate::
6acbcb92
JS
188 Pipe all output into 'less' (or if set, $PAGER).
189
463a849d
MM
190--no-pager::
191 Do not pipe git output into a pager.
192
6acbcb92
JS
193--git-dir=<path>::
194 Set the path to the repository. This can also be controlled by
302cc11a
LY
195 setting the GIT_DIR environment variable. It can be an absolute
196 path or relative path to current working directory.
6acbcb92 197
892c41b9
ML
198--work-tree=<path>::
199 Set the path to the working tree. The value will not be
200 used in combination with repositories found automatically in
201 a .git directory (i.e. $GIT_DIR is not set).
202 This can also be controlled by setting the GIT_WORK_TREE
203 environment variable and the core.worktree configuration
302cc11a
LY
204 variable. It can be an absolute path or relative path to
205 the directory specified by --git-dir or GIT_DIR.
206 Note: If --git-dir or GIT_DIR are specified but none of
207 --work-tree, GIT_WORK_TREE and core.worktree is specified,
208 the current working directory is regarded as the top directory
209 of your working tree.
892c41b9 210
6acbcb92 211--bare::
9277d602
JH
212 Treat the repository as a bare repository. If GIT_DIR
213 environment is not set, it is set to the current working
214 directory.
215
9755afbd 216
23091e95
BF
217FURTHER DOCUMENTATION
218---------------------
9755afbd 219
23091e95
BF
220See the references above to get started using git. The following is
221probably more detail than necessary for a first-time user.
8db9307c 222
40dac517 223The link:user-manual.html#git-concepts[git concepts chapter of the
6998e4db 224user-manual] and linkgit:gitcore-tutorial[7] both provide
40dac517 225introductions to the underlying git architecture.
e6fc2346 226
23091e95
BF
227See also the link:howto-index.html[howto] documents for some useful
228examples.
9755afbd 229
6998e4db
JN
230The internals are documented in the
231link:technical/api-index.html[GIT API documentation].
530e741c 232
23091e95
BF
233GIT COMMANDS
234------------
9755afbd 235
23091e95
BF
236We divide git into high level ("porcelain") commands and low level
237("plumbing") commands.
8b15e2fb 238
23091e95
BF
239High-level commands (porcelain)
240-------------------------------
241
242We separate the porcelain commands into the main commands and some
243ancillary user utilities.
244
245Main porcelain commands
246~~~~~~~~~~~~~~~~~~~~~~~
905197de 247
377e8139 248include::cmds-mainporcelain.txt[]
e31bb3bb 249
90933efb 250Ancillary Commands
23091e95 251~~~~~~~~~~~~~~~~~~
2f2de9b4
JH
252Manipulators:
253
377e8139 254include::cmds-ancillarymanipulators.txt[]
204ee6a9 255
90933efb 256Interrogators:
204ee6a9 257
377e8139 258include::cmds-ancillaryinterrogators.txt[]
7fc9d69f 259
89bf2077
JH
260
261Interacting with Others
262~~~~~~~~~~~~~~~~~~~~~~~
263
264These commands are to interact with foreign SCM and with other
265people via patch over e-mail.
266
267include::cmds-foreignscminterface.txt[]
268
269
b1f33d62
RR
270Low-level commands (plumbing)
271-----------------------------
272
273Although git includes its
274own porcelain layer, its low-level commands are sufficient to support
275development of alternative porcelains. Developers of such porcelains
5162e697
DM
276might start by reading about linkgit:git-update-index[1] and
277linkgit:git-read-tree[1].
b1f33d62 278
89bf2077
JH
279The interface (input, output, set of options and the semantics)
280to these low-level commands are meant to be a lot more stable
281than Porcelain level commands, because these commands are
282primarily for scripted use. The interface to Porcelain commands
283on the other hand are subject to change in order to improve the
284end user experience.
285
286The following description divides
287the low-level commands into commands that manipulate objects (in
b1f33d62
RR
288the repository, index, and working tree), commands that interrogate and
289compare objects, and commands that move objects and references between
290repositories.
291
89bf2077 292
b1f33d62
RR
293Manipulation commands
294~~~~~~~~~~~~~~~~~~~~~
b1f33d62 295
377e8139 296include::cmds-plumbingmanipulators.txt[]
b1f33d62
RR
297
298
299Interrogation commands
300~~~~~~~~~~~~~~~~~~~~~~
301
377e8139 302include::cmds-plumbinginterrogators.txt[]
b1f33d62
RR
303
304In general, the interrogate commands do not touch the files in
305the working tree.
306
307
308Synching repositories
309~~~~~~~~~~~~~~~~~~~~~
310
377e8139 311include::cmds-synchingrepositories.txt[]
b1f33d62 312
89bf2077
JH
313The following are helper programs used by the above; end users
314typically do not use them directly.
315
316include::cmds-synchelpers.txt[]
317
318
319Internal helper commands
320~~~~~~~~~~~~~~~~~~~~~~~~
321
322These are internal helper commands used by other commands; end
323users typically do not use them directly.
324
325include::cmds-purehelpers.txt[]
326
b1f33d62 327
5773c9f2
JH
328Configuration Mechanism
329-----------------------
330
2fa090b6 331Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
5773c9f2 332is used to hold per-repository configuration options. It is a
addf88e4 333simple text file modeled after `.ini` format familiar to some
5773c9f2
JH
334people. Here is an example:
335
336------------
337#
2fa090b6 338# A '#' or ';' character indicates a comment.
5773c9f2
JH
339#
340
341; core variables
342[core]
343 ; Don't trust file modes
344 filemode = false
345
346; user identity
347[user]
348 name = "Junio C Hamano"
349 email = "junkio@twinsun.com"
350
351------------
352
353Various commands read from the configuration file and adjust
354their operation accordingly.
355
356
6c84e2e0 357Identifier Terminology
2cf565c5
DG
358----------------------
359<object>::
2fa090b6 360 Indicates the object name for any type of object.
2cf565c5
DG
361
362<blob>::
2fa090b6 363 Indicates a blob object name.
2cf565c5
DG
364
365<tree>::
2fa090b6 366 Indicates a tree object name.
2cf565c5
DG
367
368<commit>::
2fa090b6 369 Indicates a commit object name.
2cf565c5
DG
370
371<tree-ish>::
2fa090b6 372 Indicates a tree, commit or tag object name. A
6c84e2e0
DG
373 command that takes a <tree-ish> argument ultimately wants to
374 operate on a <tree> object but automatically dereferences
375 <commit> and <tag> objects that point at a <tree>.
2cf565c5 376
043d7605
TT
377<commit-ish>::
378 Indicates a commit or tag object name. A
379 command that takes a <commit-ish> argument ultimately wants to
380 operate on a <commit> object but automatically dereferences
381 <tag> objects that point at a <commit>.
382
2cf565c5
DG
383<type>::
384 Indicates that an object type is required.
2fa090b6 385 Currently one of: `blob`, `tree`, `commit`, or `tag`.
2cf565c5
DG
386
387<file>::
2fa090b6
JH
388 Indicates a filename - almost always relative to the
389 root of the tree structure `GIT_INDEX_FILE` describes.
2cf565c5 390
c1bdacf9
DG
391Symbolic Identifiers
392--------------------
90933efb 393Any git command accepting any <object> can also use the following
6c84e2e0 394symbolic notation:
c1bdacf9
DG
395
396HEAD::
2fa090b6
JH
397 indicates the head of the current branch (i.e. the
398 contents of `$GIT_DIR/HEAD`).
399
c1bdacf9 400<tag>::
2fa090b6
JH
401 a valid tag 'name'
402 (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`).
403
c1bdacf9 404<head>::
2fa090b6
JH
405 a valid head 'name'
406 (i.e. the contents of `$GIT_DIR/refs/heads/<head>`).
407
d47107d8 408For a more complete list of ways to spell object names, see
5162e697 409"SPECIFYING REVISIONS" section in linkgit:git-rev-parse[1].
d47107d8 410
c1bdacf9
DG
411
412File/Directory Structure
413------------------------
c1bdacf9 414
6998e4db 415Please see the linkgit:gitrepository-layout[5] document.
c1bdacf9 416
6998e4db 417Read linkgit:githooks[5] for more details about each hook.
6250ad1e 418
c1bdacf9 419Higher level SCMs may provide and manage additional information in the
2fa090b6 420`$GIT_DIR`.
c1bdacf9 421
a1d4aa74 422
2cf565c5
DG
423Terminology
424-----------
6998e4db 425Please see linkgit:gitglossary[7].
2cf565c5
DG
426
427
428Environment Variables
429---------------------
430Various git commands use the following environment variables:
431
c1bdacf9
DG
432The git Repository
433~~~~~~~~~~~~~~~~~~
434These environment variables apply to 'all' core git commands. Nb: it
435is worth noting that they may be used/overridden by SCMS sitting above
2fa090b6 436git so take care if using Cogito etc.
c1bdacf9
DG
437
438'GIT_INDEX_FILE'::
439 This environment allows the specification of an alternate
5f3aa197
LS
440 index file. If not specified, the default of `$GIT_DIR/index`
441 is used.
c1bdacf9
DG
442
443'GIT_OBJECT_DIRECTORY'::
444 If the object storage directory is specified via this
445 environment variable then the sha1 directories are created
446 underneath - otherwise the default `$GIT_DIR/objects`
447 directory is used.
448
449'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
450 Due to the immutable nature of git objects, old objects can be
451 archived into shared, read-only directories. This variable
80ba074f
JS
452 specifies a ":" separated (on Windows ";" separated) list
453 of git object directories which can be used to search for git
454 objects. New objects will not be written to these directories.
c1bdacf9
DG
455
456'GIT_DIR'::
2fa090b6
JH
457 If the 'GIT_DIR' environment variable is set then it
458 specifies a path to use instead of the default `.git`
459 for the base of the repository.
c1bdacf9 460
892c41b9
ML
461'GIT_WORK_TREE'::
462 Set the path to the working tree. The value will not be
463 used in combination with repositories found automatically in
464 a .git directory (i.e. $GIT_DIR is not set).
465 This can also be controlled by the '--work-tree' command line
466 option and the core.worktree configuration variable.
467
0454dd93
DR
468'GIT_CEILING_DIRECTORIES'::
469 This should be a colon-separated list of absolute paths.
470 If set, it is a list of directories that git should not chdir
471 up into while looking for a repository directory.
472 It will not exclude the current working directory or
473 a GIT_DIR set on the command line or in the environment.
474 (Useful for excluding slow-loading network directories.)
475
c1bdacf9
DG
476git Commits
477~~~~~~~~~~~
478'GIT_AUTHOR_NAME'::
479'GIT_AUTHOR_EMAIL'::
480'GIT_AUTHOR_DATE'::
481'GIT_COMMITTER_NAME'::
482'GIT_COMMITTER_EMAIL'::
4e58bf97 483'GIT_COMMITTER_DATE'::
28a94f88 484'EMAIL'::
5162e697 485 see linkgit:git-commit-tree[1]
c1bdacf9
DG
486
487git Diffs
488~~~~~~~~~
d81ed1b5 489'GIT_DIFF_OPTS'::
fde97d8a
SE
490 Only valid setting is "--unified=??" or "-u??" to set the
491 number of context lines shown when a unified diff is created.
492 This takes precedence over any "-U" or "--unified" option
493 value passed on the git diff command line.
494
d81ed1b5 495'GIT_EXTERNAL_DIFF'::
fde97d8a
SE
496 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
497 program named by it is called, instead of the diff invocation
498 described above. For a path that is added, removed, or modified,
499 'GIT_EXTERNAL_DIFF' is called with 7 parameters:
500
501 path old-file old-hex old-mode new-file new-hex new-mode
502+
503where:
504
505 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
506 contents of <old|new>,
507 <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
508 <old|new>-mode:: are the octal representation of the file modes.
509
510+
511The file parameters can point at the user's working file
512(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
513when a new file is added), or a temporary file (e.g. `old-file` in the
514index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
515temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
516+
517For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
518parameter, <path>.
2cf565c5 519
575ba9d6
ML
520other
521~~~~~
dbddb714
JN
522'GIT_MERGE_VERBOSITY'::
523 A number controlling the amount of output shown by
524 the recursive merge strategy. Overrides merge.verbosity.
5162e697 525 See linkgit:git-merge[1]
dbddb714 526
c27d205a 527'GIT_PAGER'::
a7738c77
SG
528 This environment variable overrides `$PAGER`. If it is set
529 to an empty string or to the value "cat", git will not launch
ab54cd6c
JN
530 a pager. See also the `core.pager` option in
531 linkgit:git-config[1].
c27d205a 532
d5538b41 533'GIT_SSH'::
ba020ef5
JN
534 If this environment variable is set then 'git-fetch'
535 and 'git-push' will use this command instead
2fd02c92 536 of 'ssh' when they need to connect to a remote system.
483bc4f0 537 The '$GIT_SSH' command will be given exactly two arguments:
d5538b41
SP
538 the 'username@host' (or just 'host') from the URL and the
539 shell command to execute on that remote system.
540+
541To pass options to the program that you want to list in GIT_SSH
542you will need to wrap the program and options into a shell script,
543then set GIT_SSH to refer to the shell script.
544+
545Usually it is easier to configure any desired options through your
546personal `.ssh/config` file. Please consult your ssh documentation
547for further details.
548
06f59e9f
TT
549'GIT_FLUSH'::
550 If this environment variable is set to "1", then commands such
ba020ef5
JN
551 as 'git-blame' (in incremental mode), 'git-rev-list', 'git-log',
552 and 'git-whatchanged' will force a flush of the output stream
06f59e9f
TT
553 after each commit-oriented record have been flushed. If this
554 variable is set to "0", the output of these commands will be done
555 using completely buffered I/O. If this environment variable is
556 not set, git will choose buffered or record-oriented flushing
557 based on whether stdout appears to be redirected to a file or not.
558
575ba9d6 559'GIT_TRACE'::
2886bdb1
CC
560 If this variable is set to "1", "2" or "true" (comparison
561 is case insensitive), git will print `trace:` messages on
575ba9d6
ML
562 stderr telling about alias expansion, built-in command
563 execution and external command execution.
2886bdb1
CC
564 If this variable is set to an integer value greater than 1
565 and lower than 10 (strictly) then git will interpret this
566 value as an open file descriptor and will try to write the
567 trace messages into this file descriptor.
568 Alternatively, if this variable is set to an absolute path
569 (starting with a '/' character), git will interpret this
570 as a file path and will try to write the trace messages
571 into it.
575ba9d6 572
8db9307c
JH
573Discussion[[Discussion]]
574------------------------
40dac517
BF
575
576More detail on the following is available from the
577link:user-manual.html#git-concepts[git concepts chapter of the
6998e4db 578user-manual] and linkgit:gitcore-tutorial[7].
40dac517
BF
579
580A git project normally consists of a working directory with a ".git"
581subdirectory at the top level. The .git directory contains, among other
582things, a compressed object database representing the complete history
583of the project, an "index" file which links that history to the current
584contents of the working tree, and named pointers into that history such
585as tags and branch heads.
586
587The object database contains objects of three main types: blobs, which
588hold file data; trees, which point to blobs and other trees to build up
02ff6250 589directory hierarchies; and commits, which each reference a single tree
40dac517
BF
590and some number of parent commits.
591
592The commit, equivalent to what other systems call a "changeset" or
593"version", represents a step in the project's history, and each parent
594represents an immediately preceding step. Commits with more than one
595parent represent merges of independent lines of development.
596
597All objects are named by the SHA1 hash of their contents, normally
598written as a string of 40 hex digits. Such names are globally unique.
599The entire history leading up to a commit can be vouched for by signing
600just that commit. A fourth object type, the tag, is provided for this
601purpose.
602
603When first created, objects are stored in individual files, but for
604efficiency may later be compressed together into "pack files".
605
606Named pointers called refs mark interesting points in history. A ref
607may contain the SHA1 name of an object or the name of another ref. Refs
608with names beginning `ref/head/` contain the SHA1 name of the most
02ff6250 609recent commit (or "head") of a branch under development. SHA1 names of
40dac517
BF
610tags of interest are stored under `ref/tags/`. A special ref named
611`HEAD` contains the name of the currently checked-out branch.
612
613The index file is initialized with a list of all paths and, for each
614path, a blob object and a set of attributes. The blob object represents
615the contents of the file as of the head of the current branch. The
616attributes (last modified time, size, etc.) are taken from the
617corresponding file in the working tree. Subsequent changes to the
618working tree can be found by comparing these attributes. The index may
619be updated with new content, and new commits may be created from the
620content stored in the index.
621
622The index is also capable of storing multiple entries (called "stages")
623for a given pathname. These stages are used to hold the various
624unmerged version of a file when a merge is in progress.
6c84e2e0 625
cb22bc44
AE
626Authors
627-------
9755afbd 628* git's founding father is Linus Torvalds <torvalds@osdl.org>.
947ad2e1 629* The current git nurse is Junio C Hamano <gitster@pobox.com>.
0240e21a 630* The git potty was written by Andreas Ericsson <ae@op5.se>.
9755afbd 631* General upbringing is handled by the git-list <git@vger.kernel.org>.
2cf565c5
DG
632
633Documentation
634--------------
9755afbd
JH
635The documentation for git suite was started by David Greaves
636<david@dgreaves.com>, and later enhanced greatly by the
637contributors on the git-list <git@vger.kernel.org>.
2cf565c5 638
497c8331
CC
639SEE ALSO
640--------
641linkgit:gittutorial[7], linkgit:gittutorial-2[7],
5cbef01a 642link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
497c8331 643linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
dc493084 644linkgit:gitcli[7], link:user-manual.html[The Git User's Manual]
497c8331 645
2cf565c5
DG
646GIT
647---
9e1f0a85 648Part of the linkgit:git[1] suite