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1git(1)
2======
3
4NAME
5----
6git - the stupid content tracker
7
8
9SYNOPSIS
10--------
11[verse]
12'git' [-v | --version] [-h | --help] [-C <path>] [-c <name>=<value>]
13 [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
14 [-p|--paginate|-P|--no-pager] [--no-replace-objects] [--bare]
15 [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
16 [--super-prefix=<path>] [--config-env=<name>=<envvar>]
17 <command> [<args>]
18
19DESCRIPTION
20-----------
21Git is a fast, scalable, distributed revision control system with an
22unusually rich command set that provides both high-level operations
23and full access to internals.
24
25See linkgit:gittutorial[7] to get started, then see
26linkgit:giteveryday[7] for a useful minimum set of
27commands. The link:user-manual.html[Git User's Manual] has a more
28in-depth introduction.
29
30After you mastered the basic concepts, you can come back to this
31page to learn what commands Git offers. You can learn more about
32individual Git commands with "git help command". linkgit:gitcli[7]
33manual page gives you an overview of the command-line command syntax.
34
35A formatted and hyperlinked copy of the latest Git documentation
36can be viewed at https://git.github.io/htmldocs/git.html
37or https://git-scm.com/docs.
38
39
40OPTIONS
41-------
42-v::
43--version::
44 Prints the Git suite version that the 'git' program came from.
45+
46This option is internally converted to `git version ...` and accepts
47the same options as the linkgit:git-version[1] command. If `--help` is
48also given, it takes precedence over `--version`.
49
50-h::
51--help::
52 Prints the synopsis and a list of the most commonly used
53 commands. If the option `--all` or `-a` is given then all
54 available commands are printed. If a Git command is named this
55 option will bring up the manual page for that command.
56+
57Other options are available to control how the manual page is
58displayed. See linkgit:git-help[1] for more information,
59because `git --help ...` is converted internally into `git
60help ...`.
61
62-C <path>::
63 Run as if git was started in '<path>' instead of the current working
64 directory. When multiple `-C` options are given, each subsequent
65 non-absolute `-C <path>` is interpreted relative to the preceding `-C
66 <path>`. If '<path>' is present but empty, e.g. `-C ""`, then the
67 current working directory is left unchanged.
68+
69This option affects options that expect path name like `--git-dir` and
70`--work-tree` in that their interpretations of the path names would be
71made relative to the working directory caused by the `-C` option. For
72example the following invocations are equivalent:
73
74 git --git-dir=a.git --work-tree=b -C c status
75 git --git-dir=c/a.git --work-tree=c/b status
76
77-c <name>=<value>::
78 Pass a configuration parameter to the command. The value
79 given will override values from configuration files.
80 The <name> is expected in the same format as listed by
81 'git config' (subkeys separated by dots).
82+
83Note that omitting the `=` in `git -c foo.bar ...` is allowed and sets
84`foo.bar` to the boolean true value (just like `[foo]bar` would in a
85config file). Including the equals but with an empty value (like `git -c
86foo.bar= ...`) sets `foo.bar` to the empty string which `git config
87--type=bool` will convert to `false`.
88
89--config-env=<name>=<envvar>::
90 Like `-c <name>=<value>`, give configuration variable
91 '<name>' a value, where <envvar> is the name of an
92 environment variable from which to retrieve the value. Unlike
93 `-c` there is no shortcut for directly setting the value to an
94 empty string, instead the environment variable itself must be
95 set to the empty string. It is an error if the `<envvar>` does not exist
96 in the environment. `<envvar>` may not contain an equals sign
97 to avoid ambiguity with `<name>` containing one.
98+
99This is useful for cases where you want to pass transitory
100configuration options to git, but are doing so on OS's where
101other processes might be able to read your cmdline
102(e.g. `/proc/self/cmdline`), but not your environ
103(e.g. `/proc/self/environ`). That behavior is the default on
104Linux, but may not be on your system.
105+
106Note that this might add security for variables such as
107`http.extraHeader` where the sensitive information is part of
108the value, but not e.g. `url.<base>.insteadOf` where the
109sensitive information can be part of the key.
110
111--exec-path[=<path>]::
112 Path to wherever your core Git programs are installed.
113 This can also be controlled by setting the GIT_EXEC_PATH
114 environment variable. If no path is given, 'git' will print
115 the current setting and then exit.
116
117--html-path::
118 Print the path, without trailing slash, where Git's HTML
119 documentation is installed and exit.
120
121--man-path::
122 Print the manpath (see `man(1)`) for the man pages for
123 this version of Git and exit.
124
125--info-path::
126 Print the path where the Info files documenting this
127 version of Git are installed and exit.
128
129-p::
130--paginate::
131 Pipe all output into 'less' (or if set, $PAGER) if standard
132 output is a terminal. This overrides the `pager.<cmd>`
133 configuration options (see the "Configuration Mechanism" section
134 below).
135
136-P::
137--no-pager::
138 Do not pipe Git output into a pager.
139
140--git-dir=<path>::
141 Set the path to the repository (".git" directory). This can also be
142 controlled by setting the `GIT_DIR` environment variable. It can be
143 an absolute path or relative path to current working directory.
144+
145Specifying the location of the ".git" directory using this
146option (or `GIT_DIR` environment variable) turns off the
147repository discovery that tries to find a directory with
148".git" subdirectory (which is how the repository and the
149top-level of the working tree are discovered), and tells Git
150that you are at the top level of the working tree. If you
151are not at the top-level directory of the working tree, you
152should tell Git where the top-level of the working tree is,
153with the `--work-tree=<path>` option (or `GIT_WORK_TREE`
154environment variable)
155+
156If you just want to run git as if it was started in `<path>` then use
157`git -C <path>`.
158
159--work-tree=<path>::
160 Set the path to the working tree. It can be an absolute path
161 or a path relative to the current working directory.
162 This can also be controlled by setting the GIT_WORK_TREE
163 environment variable and the core.worktree configuration
164 variable (see core.worktree in linkgit:git-config[1] for a
165 more detailed discussion).
166
167--namespace=<path>::
168 Set the Git namespace. See linkgit:gitnamespaces[7] for more
169 details. Equivalent to setting the `GIT_NAMESPACE` environment
170 variable.
171
172--super-prefix=<path>::
173 Currently for internal use only. Set a prefix which gives a path from
174 above a repository down to its root. One use is to give submodules
175 context about the superproject that invoked it.
176
177--bare::
178 Treat the repository as a bare repository. If GIT_DIR
179 environment is not set, it is set to the current working
180 directory.
181
182--no-replace-objects::
183 Do not use replacement refs to replace Git objects. See
184 linkgit:git-replace[1] for more information.
185
186--literal-pathspecs::
187 Treat pathspecs literally (i.e. no globbing, no pathspec magic).
188 This is equivalent to setting the `GIT_LITERAL_PATHSPECS` environment
189 variable to `1`.
190
191--glob-pathspecs::
192 Add "glob" magic to all pathspec. This is equivalent to setting
193 the `GIT_GLOB_PATHSPECS` environment variable to `1`. Disabling
194 globbing on individual pathspecs can be done using pathspec
195 magic ":(literal)"
196
197--noglob-pathspecs::
198 Add "literal" magic to all pathspec. This is equivalent to setting
199 the `GIT_NOGLOB_PATHSPECS` environment variable to `1`. Enabling
200 globbing on individual pathspecs can be done using pathspec
201 magic ":(glob)"
202
203--icase-pathspecs::
204 Add "icase" magic to all pathspec. This is equivalent to setting
205 the `GIT_ICASE_PATHSPECS` environment variable to `1`.
206
207--no-optional-locks::
208 Do not perform optional operations that require locks. This is
209 equivalent to setting the `GIT_OPTIONAL_LOCKS` to `0`.
210
211--list-cmds=group[,group...]::
212 List commands by group. This is an internal/experimental
213 option and may change or be removed in the future. Supported
214 groups are: builtins, parseopt (builtin commands that use
215 parse-options), main (all commands in libexec directory),
216 others (all other commands in `$PATH` that have git- prefix),
217 list-<category> (see categories in command-list.txt),
218 nohelpers (exclude helper commands), alias and config
219 (retrieve command list from config variable completion.commands)
220
221GIT COMMANDS
222------------
223
224We divide Git into high level ("porcelain") commands and low level
225("plumbing") commands.
226
227High-level commands (porcelain)
228-------------------------------
229
230We separate the porcelain commands into the main commands and some
231ancillary user utilities.
232
233Main porcelain commands
234~~~~~~~~~~~~~~~~~~~~~~~
235
236include::cmds-mainporcelain.txt[]
237
238Ancillary Commands
239~~~~~~~~~~~~~~~~~~
240Manipulators:
241
242include::cmds-ancillarymanipulators.txt[]
243
244Interrogators:
245
246include::cmds-ancillaryinterrogators.txt[]
247
248
249Interacting with Others
250~~~~~~~~~~~~~~~~~~~~~~~
251
252These commands are to interact with foreign SCM and with other
253people via patch over e-mail.
254
255include::cmds-foreignscminterface.txt[]
256
257Reset, restore and revert
258~~~~~~~~~~~~~~~~~~~~~~~~~
259There are three commands with similar names: `git reset`,
260`git restore` and `git revert`.
261
262* linkgit:git-revert[1] is about making a new commit that reverts the
263 changes made by other commits.
264
265* linkgit:git-restore[1] is about restoring files in the working tree
266 from either the index or another commit. This command does not
267 update your branch. The command can also be used to restore files in
268 the index from another commit.
269
270* linkgit:git-reset[1] is about updating your branch, moving the tip
271 in order to add or remove commits from the branch. This operation
272 changes the commit history.
273+
274`git reset` can also be used to restore the index, overlapping with
275`git restore`.
276
277
278Low-level commands (plumbing)
279-----------------------------
280
281Although Git includes its
282own porcelain layer, its low-level commands are sufficient to support
283development of alternative porcelains. Developers of such porcelains
284might start by reading about linkgit:git-update-index[1] and
285linkgit:git-read-tree[1].
286
287The interface (input, output, set of options and the semantics)
288to these low-level commands are meant to be a lot more stable
289than Porcelain level commands, because these commands are
290primarily for scripted use. The interface to Porcelain commands
291on the other hand are subject to change in order to improve the
292end user experience.
293
294The following description divides
295the low-level commands into commands that manipulate objects (in
296the repository, index, and working tree), commands that interrogate and
297compare objects, and commands that move objects and references between
298repositories.
299
300
301Manipulation commands
302~~~~~~~~~~~~~~~~~~~~~
303
304include::cmds-plumbingmanipulators.txt[]
305
306
307Interrogation commands
308~~~~~~~~~~~~~~~~~~~~~~
309
310include::cmds-plumbinginterrogators.txt[]
311
312In general, the interrogate commands do not touch the files in
313the working tree.
314
315
316Syncing repositories
317~~~~~~~~~~~~~~~~~~~~
318
319include::cmds-synchingrepositories.txt[]
320
321The following are helper commands used by the above; end users
322typically do not use them directly.
323
324include::cmds-synchelpers.txt[]
325
326
327Internal helper commands
328~~~~~~~~~~~~~~~~~~~~~~~~
329
330These are internal helper commands used by other commands; end
331users typically do not use them directly.
332
333include::cmds-purehelpers.txt[]
334
335Guides
336------
337
338The following documentation pages are guides about Git concepts.
339
340include::cmds-guide.txt[]
341
342
343Configuration Mechanism
344-----------------------
345
346Git uses a simple text format to store customizations that are per
347repository and are per user. Such a configuration file may look
348like this:
349
350------------
351#
352# A '#' or ';' character indicates a comment.
353#
354
355; core variables
356[core]
357 ; Don't trust file modes
358 filemode = false
359
360; user identity
361[user]
362 name = "Junio C Hamano"
363 email = "gitster@pobox.com"
364
365------------
366
367Various commands read from the configuration file and adjust
368their operation accordingly. See linkgit:git-config[1] for a
369list and more details about the configuration mechanism.
370
371
372Identifier Terminology
373----------------------
374<object>::
375 Indicates the object name for any type of object.
376
377<blob>::
378 Indicates a blob object name.
379
380<tree>::
381 Indicates a tree object name.
382
383<commit>::
384 Indicates a commit object name.
385
386<tree-ish>::
387 Indicates a tree, commit or tag object name. A
388 command that takes a <tree-ish> argument ultimately wants to
389 operate on a <tree> object but automatically dereferences
390 <commit> and <tag> objects that point at a <tree>.
391
392<commit-ish>::
393 Indicates a commit or tag object name. A
394 command that takes a <commit-ish> argument ultimately wants to
395 operate on a <commit> object but automatically dereferences
396 <tag> objects that point at a <commit>.
397
398<type>::
399 Indicates that an object type is required.
400 Currently one of: `blob`, `tree`, `commit`, or `tag`.
401
402<file>::
403 Indicates a filename - almost always relative to the
404 root of the tree structure `GIT_INDEX_FILE` describes.
405
406Symbolic Identifiers
407--------------------
408Any Git command accepting any <object> can also use the following
409symbolic notation:
410
411HEAD::
412 indicates the head of the current branch.
413
414<tag>::
415 a valid tag 'name'
416 (i.e. a `refs/tags/<tag>` reference).
417
418<head>::
419 a valid head 'name'
420 (i.e. a `refs/heads/<head>` reference).
421
422For a more complete list of ways to spell object names, see
423"SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
424
425
426File/Directory Structure
427------------------------
428
429Please see the linkgit:gitrepository-layout[5] document.
430
431Read linkgit:githooks[5] for more details about each hook.
432
433Higher level SCMs may provide and manage additional information in the
434`$GIT_DIR`.
435
436
437Terminology
438-----------
439Please see linkgit:gitglossary[7].
440
441
442Environment Variables
443---------------------
444Various Git commands pay attention to environment variables and change
445their behavior. The environment variables marked as "Boolean" take
446their values the same way as Boolean valued configuration variables, e.g.
447"true", "yes", "on" and positive numbers are taken as "yes".
448
449Here are the variables:
450
451The Git Repository
452~~~~~~~~~~~~~~~~~~
453These environment variables apply to 'all' core Git commands. Nb: it
454is worth noting that they may be used/overridden by SCMS sitting above
455Git so take care if using a foreign front-end.
456
457`GIT_INDEX_FILE`::
458 This environment variable specifies an alternate
459 index file. If not specified, the default of `$GIT_DIR/index`
460 is used.
461
462`GIT_INDEX_VERSION`::
463 This environment variable specifies what index version is used
464 when writing the index file out. It won't affect existing index
465 files. By default index file version 2 or 3 is used. See
466 linkgit:git-update-index[1] for more information.
467
468`GIT_OBJECT_DIRECTORY`::
469 If the object storage directory is specified via this
470 environment variable then the sha1 directories are created
471 underneath - otherwise the default `$GIT_DIR/objects`
472 directory is used.
473
474`GIT_ALTERNATE_OBJECT_DIRECTORIES`::
475 Due to the immutable nature of Git objects, old objects can be
476 archived into shared, read-only directories. This variable
477 specifies a ":" separated (on Windows ";" separated) list
478 of Git object directories which can be used to search for Git
479 objects. New objects will not be written to these directories.
480+
481Entries that begin with `"` (double-quote) will be interpreted
482as C-style quoted paths, removing leading and trailing
483double-quotes and respecting backslash escapes. E.g., the value
484`"path-with-\"-and-:-in-it":vanilla-path` has two paths:
485`path-with-"-and-:-in-it` and `vanilla-path`.
486
487`GIT_DIR`::
488 If the `GIT_DIR` environment variable is set then it
489 specifies a path to use instead of the default `.git`
490 for the base of the repository.
491 The `--git-dir` command-line option also sets this value.
492
493`GIT_WORK_TREE`::
494 Set the path to the root of the working tree.
495 This can also be controlled by the `--work-tree` command-line
496 option and the core.worktree configuration variable.
497
498`GIT_NAMESPACE`::
499 Set the Git namespace; see linkgit:gitnamespaces[7] for details.
500 The `--namespace` command-line option also sets this value.
501
502`GIT_CEILING_DIRECTORIES`::
503 This should be a colon-separated list of absolute paths. If
504 set, it is a list of directories that Git should not chdir up
505 into while looking for a repository directory (useful for
506 excluding slow-loading network directories). It will not
507 exclude the current working directory or a GIT_DIR set on the
508 command line or in the environment. Normally, Git has to read
509 the entries in this list and resolve any symlink that
510 might be present in order to compare them with the current
511 directory. However, if even this access is slow, you
512 can add an empty entry to the list to tell Git that the
513 subsequent entries are not symlinks and needn't be resolved;
514 e.g.,
515 `GIT_CEILING_DIRECTORIES=/maybe/symlink::/very/slow/non/symlink`.
516
517`GIT_DISCOVERY_ACROSS_FILESYSTEM`::
518 When run in a directory that does not have ".git" repository
519 directory, Git tries to find such a directory in the parent
520 directories to find the top of the working tree, but by default it
521 does not cross filesystem boundaries. This Boolean environment variable
522 can be set to true to tell Git not to stop at filesystem
523 boundaries. Like `GIT_CEILING_DIRECTORIES`, this will not affect
524 an explicit repository directory set via `GIT_DIR` or on the
525 command line.
526
527`GIT_COMMON_DIR`::
528 If this variable is set to a path, non-worktree files that are
529 normally in $GIT_DIR will be taken from this path
530 instead. Worktree-specific files such as HEAD or index are
531 taken from $GIT_DIR. See linkgit:gitrepository-layout[5] and
532 linkgit:git-worktree[1] for
533 details. This variable has lower precedence than other path
534 variables such as GIT_INDEX_FILE, GIT_OBJECT_DIRECTORY...
535
536`GIT_DEFAULT_HASH`::
537 If this variable is set, the default hash algorithm for new
538 repositories will be set to this value. This value is currently
539 ignored when cloning; the setting of the remote repository
540 is used instead. The default is "sha1". THIS VARIABLE IS
541 EXPERIMENTAL! See `--object-format` in linkgit:git-init[1].
542
543Git Commits
544~~~~~~~~~~~
545`GIT_AUTHOR_NAME`::
546 The human-readable name used in the author identity when creating commit or
547 tag objects, or when writing reflogs. Overrides the `user.name` and
548 `author.name` configuration settings.
549
550`GIT_AUTHOR_EMAIL`::
551 The email address used in the author identity when creating commit or
552 tag objects, or when writing reflogs. Overrides the `user.email` and
553 `author.email` configuration settings.
554
555`GIT_AUTHOR_DATE`::
556 The date used for the author identity when creating commit or tag objects, or
557 when writing reflogs. See linkgit:git-commit[1] for valid formats.
558
559`GIT_COMMITTER_NAME`::
560 The human-readable name used in the committer identity when creating commit or
561 tag objects, or when writing reflogs. Overrides the `user.name` and
562 `committer.name` configuration settings.
563
564`GIT_COMMITTER_EMAIL`::
565 The email address used in the author identity when creating commit or
566 tag objects, or when writing reflogs. Overrides the `user.email` and
567 `committer.email` configuration settings.
568
569`GIT_COMMITTER_DATE`::
570 The date used for the committer identity when creating commit or tag objects, or
571 when writing reflogs. See linkgit:git-commit[1] for valid formats.
572
573`EMAIL`::
574 The email address used in the author and committer identities if no other
575 relevant environment variable or configuration setting has been set.
576
577Git Diffs
578~~~~~~~~~
579`GIT_DIFF_OPTS`::
580 Only valid setting is "--unified=??" or "-u??" to set the
581 number of context lines shown when a unified diff is created.
582 This takes precedence over any "-U" or "--unified" option
583 value passed on the Git diff command line.
584
585`GIT_EXTERNAL_DIFF`::
586 When the environment variable `GIT_EXTERNAL_DIFF` is set, the
587 program named by it is called to generate diffs, and Git
588 does not use its builtin diff machinery.
589 For a path that is added, removed, or modified,
590 `GIT_EXTERNAL_DIFF` is called with 7 parameters:
591
592 path old-file old-hex old-mode new-file new-hex new-mode
593+
594where:
595
596 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
597 contents of <old|new>,
598 <old|new>-hex:: are the 40-hexdigit SHA-1 hashes,
599 <old|new>-mode:: are the octal representation of the file modes.
600+
601The file parameters can point at the user's working file
602(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
603when a new file is added), or a temporary file (e.g. `old-file` in the
604index). `GIT_EXTERNAL_DIFF` should not worry about unlinking the
605temporary file --- it is removed when `GIT_EXTERNAL_DIFF` exits.
606+
607For a path that is unmerged, `GIT_EXTERNAL_DIFF` is called with 1
608parameter, <path>.
609+
610For each path `GIT_EXTERNAL_DIFF` is called, two environment variables,
611`GIT_DIFF_PATH_COUNTER` and `GIT_DIFF_PATH_TOTAL` are set.
612
613`GIT_DIFF_PATH_COUNTER`::
614 A 1-based counter incremented by one for every path.
615
616`GIT_DIFF_PATH_TOTAL`::
617 The total number of paths.
618
619other
620~~~~~
621`GIT_MERGE_VERBOSITY`::
622 A number controlling the amount of output shown by
623 the recursive merge strategy. Overrides merge.verbosity.
624 See linkgit:git-merge[1]
625
626`GIT_PAGER`::
627 This environment variable overrides `$PAGER`. If it is set
628 to an empty string or to the value "cat", Git will not launch
629 a pager. See also the `core.pager` option in
630 linkgit:git-config[1].
631
632`GIT_PROGRESS_DELAY`::
633 A number controlling how many seconds to delay before showing
634 optional progress indicators. Defaults to 2.
635
636`GIT_EDITOR`::
637 This environment variable overrides `$EDITOR` and `$VISUAL`.
638 It is used by several Git commands when, on interactive mode,
639 an editor is to be launched. See also linkgit:git-var[1]
640 and the `core.editor` option in linkgit:git-config[1].
641
642`GIT_SEQUENCE_EDITOR`::
643 This environment variable overrides the configured Git editor
644 when editing the todo list of an interactive rebase. See also
645 linkgit:git-rebase[1] and the `sequence.editor` option in
646 linkgit:git-config[1].
647
648`GIT_SSH`::
649`GIT_SSH_COMMAND`::
650 If either of these environment variables is set then 'git fetch'
651 and 'git push' will use the specified command instead of 'ssh'
652 when they need to connect to a remote system.
653 The command-line parameters passed to the configured command are
654 determined by the ssh variant. See `ssh.variant` option in
655 linkgit:git-config[1] for details.
656+
657`$GIT_SSH_COMMAND` takes precedence over `$GIT_SSH`, and is interpreted
658by the shell, which allows additional arguments to be included.
659`$GIT_SSH` on the other hand must be just the path to a program
660(which can be a wrapper shell script, if additional arguments are
661needed).
662+
663Usually it is easier to configure any desired options through your
664personal `.ssh/config` file. Please consult your ssh documentation
665for further details.
666
667`GIT_SSH_VARIANT`::
668 If this environment variable is set, it overrides Git's autodetection
669 whether `GIT_SSH`/`GIT_SSH_COMMAND`/`core.sshCommand` refer to OpenSSH,
670 plink or tortoiseplink. This variable overrides the config setting
671 `ssh.variant` that serves the same purpose.
672
673`GIT_SSL_NO_VERIFY`::
674 Setting and exporting this environment variable to any value
675 tells Git not to verify the SSL certificate when fetching or
676 pushing over HTTPS.
677
678`GIT_ASKPASS`::
679 If this environment variable is set, then Git commands which need to
680 acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
681 will call this program with a suitable prompt as command-line argument
682 and read the password from its STDOUT. See also the `core.askPass`
683 option in linkgit:git-config[1].
684
685`GIT_TERMINAL_PROMPT`::
686 If this Boolean environment variable is set to false, git will not prompt
687 on the terminal (e.g., when asking for HTTP authentication).
688
689`GIT_CONFIG_GLOBAL`::
690`GIT_CONFIG_SYSTEM`::
691 Take the configuration from the given files instead from global or
692 system-level configuration files. If `GIT_CONFIG_SYSTEM` is set, the
693 system config file defined at build time (usually `/etc/gitconfig`)
694 will not be read. Likewise, if `GIT_CONFIG_GLOBAL` is set, neither
695 `$HOME/.gitconfig` nor `$XDG_CONFIG_HOME/git/config` will be read. Can
696 be set to `/dev/null` to skip reading configuration files of the
697 respective level.
698
699`GIT_CONFIG_NOSYSTEM`::
700 Whether to skip reading settings from the system-wide
701 `$(prefix)/etc/gitconfig` file. This Boolean environment variable can
702 be used along with `$HOME` and `$XDG_CONFIG_HOME` to create a
703 predictable environment for a picky script, or you can set it
704 to true to temporarily avoid using a buggy `/etc/gitconfig` file while
705 waiting for someone with sufficient permissions to fix it.
706
707`GIT_FLUSH`::
708// NEEDSWORK: make it into a usual Boolean environment variable
709 If this environment variable is set to "1", then commands such
710 as 'git blame' (in incremental mode), 'git rev-list', 'git log',
711 'git check-attr' and 'git check-ignore' will
712 force a flush of the output stream after each record have been
713 flushed. If this
714 variable is set to "0", the output of these commands will be done
715 using completely buffered I/O. If this environment variable is
716 not set, Git will choose buffered or record-oriented flushing
717 based on whether stdout appears to be redirected to a file or not.
718
719`GIT_TRACE`::
720 Enables general trace messages, e.g. alias expansion, built-in
721 command execution and external command execution.
722+
723If this variable is set to "1", "2" or "true" (comparison
724is case insensitive), trace messages will be printed to
725stderr.
726+
727If the variable is set to an integer value greater than 2
728and lower than 10 (strictly) then Git will interpret this
729value as an open file descriptor and will try to write the
730trace messages into this file descriptor.
731+
732Alternatively, if the variable is set to an absolute path
733(starting with a '/' character), Git will interpret this
734as a file path and will try to append the trace messages
735to it.
736+
737Unsetting the variable, or setting it to empty, "0" or
738"false" (case insensitive) disables trace messages.
739
740`GIT_TRACE_FSMONITOR`::
741 Enables trace messages for the filesystem monitor extension.
742 See `GIT_TRACE` for available trace output options.
743
744`GIT_TRACE_PACK_ACCESS`::
745 Enables trace messages for all accesses to any packs. For each
746 access, the pack file name and an offset in the pack is
747 recorded. This may be helpful for troubleshooting some
748 pack-related performance problems.
749 See `GIT_TRACE` for available trace output options.
750
751`GIT_TRACE_PACKET`::
752 Enables trace messages for all packets coming in or out of a
753 given program. This can help with debugging object negotiation
754 or other protocol issues. Tracing is turned off at a packet
755 starting with "PACK" (but see `GIT_TRACE_PACKFILE` below).
756 See `GIT_TRACE` for available trace output options.
757
758`GIT_TRACE_PACKFILE`::
759 Enables tracing of packfiles sent or received by a
760 given program. Unlike other trace output, this trace is
761 verbatim: no headers, and no quoting of binary data. You almost
762 certainly want to direct into a file (e.g.,
763 `GIT_TRACE_PACKFILE=/tmp/my.pack`) rather than displaying it on
764 the terminal or mixing it with other trace output.
765+
766Note that this is currently only implemented for the client side
767of clones and fetches.
768
769`GIT_TRACE_PERFORMANCE`::
770 Enables performance related trace messages, e.g. total execution
771 time of each Git command.
772 See `GIT_TRACE` for available trace output options.
773
774`GIT_TRACE_REFS`::
775 Enables trace messages for operations on the ref database.
776 See `GIT_TRACE` for available trace output options.
777
778`GIT_TRACE_SETUP`::
779 Enables trace messages printing the .git, working tree and current
780 working directory after Git has completed its setup phase.
781 See `GIT_TRACE` for available trace output options.
782
783`GIT_TRACE_SHALLOW`::
784 Enables trace messages that can help debugging fetching /
785 cloning of shallow repositories.
786 See `GIT_TRACE` for available trace output options.
787
788`GIT_TRACE_CURL`::
789 Enables a curl full trace dump of all incoming and outgoing data,
790 including descriptive information, of the git transport protocol.
791 This is similar to doing curl `--trace-ascii` on the command line.
792 See `GIT_TRACE` for available trace output options.
793
794`GIT_TRACE_CURL_NO_DATA`::
795 When a curl trace is enabled (see `GIT_TRACE_CURL` above), do not dump
796 data (that is, only dump info lines and headers).
797
798`GIT_TRACE2`::
799 Enables more detailed trace messages from the "trace2" library.
800 Output from `GIT_TRACE2` is a simple text-based format for human
801 readability.
802+
803If this variable is set to "1", "2" or "true" (comparison
804is case insensitive), trace messages will be printed to
805stderr.
806+
807If the variable is set to an integer value greater than 2
808and lower than 10 (strictly) then Git will interpret this
809value as an open file descriptor and will try to write the
810trace messages into this file descriptor.
811+
812Alternatively, if the variable is set to an absolute path
813(starting with a '/' character), Git will interpret this
814as a file path and will try to append the trace messages
815to it. If the path already exists and is a directory, the
816trace messages will be written to files (one per process)
817in that directory, named according to the last component
818of the SID and an optional counter (to avoid filename
819collisions).
820+
821In addition, if the variable is set to
822`af_unix:[<socket_type>:]<absolute-pathname>`, Git will try
823to open the path as a Unix Domain Socket. The socket type
824can be either `stream` or `dgram`.
825+
826Unsetting the variable, or setting it to empty, "0" or
827"false" (case insensitive) disables trace messages.
828+
829See link:technical/api-trace2.html[Trace2 documentation]
830for full details.
831
832
833`GIT_TRACE2_EVENT`::
834 This setting writes a JSON-based format that is suited for machine
835 interpretation.
836 See `GIT_TRACE2` for available trace output options and
837 link:technical/api-trace2.html[Trace2 documentation] for full details.
838
839`GIT_TRACE2_PERF`::
840 In addition to the text-based messages available in `GIT_TRACE2`, this
841 setting writes a column-based format for understanding nesting
842 regions.
843 See `GIT_TRACE2` for available trace output options and
844 link:technical/api-trace2.html[Trace2 documentation] for full details.
845
846`GIT_TRACE_REDACT`::
847 By default, when tracing is activated, Git redacts the values of
848 cookies, the "Authorization:" header, the "Proxy-Authorization:"
849 header and packfile URIs. Set this Boolean environment variable to false to prevent this
850 redaction.
851
852`GIT_LITERAL_PATHSPECS`::
853 Setting this Boolean environment variable to true will cause Git to treat all
854 pathspecs literally, rather than as glob patterns. For example,
855 running `GIT_LITERAL_PATHSPECS=1 git log -- '*.c'` will search
856 for commits that touch the path `*.c`, not any paths that the
857 glob `*.c` matches. You might want this if you are feeding
858 literal paths to Git (e.g., paths previously given to you by
859 `git ls-tree`, `--raw` diff output, etc).
860
861`GIT_GLOB_PATHSPECS`::
862 Setting this Boolean environment variable to true will cause Git to treat all
863 pathspecs as glob patterns (aka "glob" magic).
864
865`GIT_NOGLOB_PATHSPECS`::
866 Setting this Boolean environment variable to true will cause Git to treat all
867 pathspecs as literal (aka "literal" magic).
868
869`GIT_ICASE_PATHSPECS`::
870 Setting this Boolean environment variable to true will cause Git to treat all
871 pathspecs as case-insensitive.
872
873`GIT_REFLOG_ACTION`::
874 When a ref is updated, reflog entries are created to keep
875 track of the reason why the ref was updated (which is
876 typically the name of the high-level command that updated
877 the ref), in addition to the old and new values of the ref.
878 A scripted Porcelain command can use set_reflog_action
879 helper function in `git-sh-setup` to set its name to this
880 variable when it is invoked as the top level command by the
881 end user, to be recorded in the body of the reflog.
882
883`GIT_REF_PARANOIA`::
884 If this Boolean environment variable is set to false, ignore broken or badly named refs when iterating
885 over lists of refs. Normally Git will try to include any such
886 refs, which may cause some operations to fail. This is usually
887 preferable, as potentially destructive operations (e.g.,
888 linkgit:git-prune[1]) are better off aborting rather than
889 ignoring broken refs (and thus considering the history they
890 point to as not worth saving). The default value is `1` (i.e.,
891 be paranoid about detecting and aborting all operations). You
892 should not normally need to set this to `0`, but it may be
893 useful when trying to salvage data from a corrupted repository.
894
895`GIT_ALLOW_PROTOCOL`::
896 If set to a colon-separated list of protocols, behave as if
897 `protocol.allow` is set to `never`, and each of the listed
898 protocols has `protocol.<name>.allow` set to `always`
899 (overriding any existing configuration). See the description of
900 `protocol.allow` in linkgit:git-config[1] for more details.
901
902`GIT_PROTOCOL_FROM_USER`::
903 Set this Boolean environment variable to false to prevent protocols used by fetch/push/clone which are
904 configured to the `user` state. This is useful to restrict recursive
905 submodule initialization from an untrusted repository or for programs
906 which feed potentially-untrusted URLS to git commands. See
907 linkgit:git-config[1] for more details.
908
909`GIT_PROTOCOL`::
910 For internal use only. Used in handshaking the wire protocol.
911 Contains a colon ':' separated list of keys with optional values
912 'key[=value]'. Presence of unknown keys and values must be
913 ignored.
914+
915Note that servers may need to be configured to allow this variable to
916pass over some transports. It will be propagated automatically when
917accessing local repositories (i.e., `file://` or a filesystem path), as
918well as over the `git://` protocol. For git-over-http, it should work
919automatically in most configurations, but see the discussion in
920linkgit:git-http-backend[1]. For git-over-ssh, the ssh server may need
921to be configured to allow clients to pass this variable (e.g., by using
922`AcceptEnv GIT_PROTOCOL` with OpenSSH).
923+
924This configuration is optional. If the variable is not propagated, then
925clients will fall back to the original "v0" protocol (but may miss out
926on some performance improvements or features). This variable currently
927only affects clones and fetches; it is not yet used for pushes (but may
928be in the future).
929
930`GIT_OPTIONAL_LOCKS`::
931 If this Boolean environment variable is set to false, Git will complete any requested operation without
932 performing any optional sub-operations that require taking a lock.
933 For example, this will prevent `git status` from refreshing the
934 index as a side effect. This is useful for processes running in
935 the background which do not want to cause lock contention with
936 other operations on the repository. Defaults to `1`.
937
938`GIT_REDIRECT_STDIN`::
939`GIT_REDIRECT_STDOUT`::
940`GIT_REDIRECT_STDERR`::
941 Windows-only: allow redirecting the standard input/output/error
942 handles to paths specified by the environment variables. This is
943 particularly useful in multi-threaded applications where the
944 canonical way to pass standard handles via `CreateProcess()` is
945 not an option because it would require the handles to be marked
946 inheritable (and consequently *every* spawned process would
947 inherit them, possibly blocking regular Git operations). The
948 primary intended use case is to use named pipes for communication
949 (e.g. `\\.\pipe\my-git-stdin-123`).
950+
951Two special values are supported: `off` will simply close the
952corresponding standard handle, and if `GIT_REDIRECT_STDERR` is
953`2>&1`, standard error will be redirected to the same handle as
954standard output.
955
956`GIT_PRINT_SHA1_ELLIPSIS` (deprecated)::
957 If set to `yes`, print an ellipsis following an
958 (abbreviated) SHA-1 value. This affects indications of
959 detached HEADs (linkgit:git-checkout[1]) and the raw
960 diff output (linkgit:git-diff[1]). Printing an
961 ellipsis in the cases mentioned is no longer considered
962 adequate and support for it is likely to be removed in the
963 foreseeable future (along with the variable).
964
965Discussion[[Discussion]]
966------------------------
967
968More detail on the following is available from the
969link:user-manual.html#git-concepts[Git concepts chapter of the
970user-manual] and linkgit:gitcore-tutorial[7].
971
972A Git project normally consists of a working directory with a ".git"
973subdirectory at the top level. The .git directory contains, among other
974things, a compressed object database representing the complete history
975of the project, an "index" file which links that history to the current
976contents of the working tree, and named pointers into that history such
977as tags and branch heads.
978
979The object database contains objects of three main types: blobs, which
980hold file data; trees, which point to blobs and other trees to build up
981directory hierarchies; and commits, which each reference a single tree
982and some number of parent commits.
983
984The commit, equivalent to what other systems call a "changeset" or
985"version", represents a step in the project's history, and each parent
986represents an immediately preceding step. Commits with more than one
987parent represent merges of independent lines of development.
988
989All objects are named by the SHA-1 hash of their contents, normally
990written as a string of 40 hex digits. Such names are globally unique.
991The entire history leading up to a commit can be vouched for by signing
992just that commit. A fourth object type, the tag, is provided for this
993purpose.
994
995When first created, objects are stored in individual files, but for
996efficiency may later be compressed together into "pack files".
997
998Named pointers called refs mark interesting points in history. A ref
999may contain the SHA-1 name of an object or the name of another ref. Refs
1000with names beginning `ref/head/` contain the SHA-1 name of the most
1001recent commit (or "head") of a branch under development. SHA-1 names of
1002tags of interest are stored under `ref/tags/`. A special ref named
1003`HEAD` contains the name of the currently checked-out branch.
1004
1005The index file is initialized with a list of all paths and, for each
1006path, a blob object and a set of attributes. The blob object represents
1007the contents of the file as of the head of the current branch. The
1008attributes (last modified time, size, etc.) are taken from the
1009corresponding file in the working tree. Subsequent changes to the
1010working tree can be found by comparing these attributes. The index may
1011be updated with new content, and new commits may be created from the
1012content stored in the index.
1013
1014The index is also capable of storing multiple entries (called "stages")
1015for a given pathname. These stages are used to hold the various
1016unmerged version of a file when a merge is in progress.
1017
1018FURTHER DOCUMENTATION
1019---------------------
1020
1021See the references in the "description" section to get started
1022using Git. The following is probably more detail than necessary
1023for a first-time user.
1024
1025The link:user-manual.html#git-concepts[Git concepts chapter of the
1026user-manual] and linkgit:gitcore-tutorial[7] both provide
1027introductions to the underlying Git architecture.
1028
1029See linkgit:gitworkflows[7] for an overview of recommended workflows.
1030
1031See also the link:howto-index.html[howto] documents for some useful
1032examples.
1033
1034The internals are documented in the
1035link:technical/api-index.html[Git API documentation].
1036
1037Users migrating from CVS may also want to
1038read linkgit:gitcvs-migration[7].
1039
1040
1041Authors
1042-------
1043Git was started by Linus Torvalds, and is currently maintained by Junio
1044C Hamano. Numerous contributions have come from the Git mailing list
1045<git@vger.kernel.org>. http://www.openhub.net/p/git/contributors/summary
1046gives you a more complete list of contributors.
1047
1048If you have a clone of git.git itself, the
1049output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
1050the authors for specific parts of the project.
1051
1052Reporting Bugs
1053--------------
1054
1055Report bugs to the Git mailing list <git@vger.kernel.org> where the
1056development and maintenance is primarily done. You do not have to be
1057subscribed to the list to send a message there. See the list archive
1058at https://lore.kernel.org/git for previous bug reports and other
1059discussions.
1060
1061Issues which are security relevant should be disclosed privately to
1062the Git Security mailing list <git-security@googlegroups.com>.
1063
1064SEE ALSO
1065--------
1066linkgit:gittutorial[7], linkgit:gittutorial-2[7],
1067linkgit:giteveryday[7], linkgit:gitcvs-migration[7],
1068linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
1069linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
1070linkgit:gitworkflows[7]
1071
1072GIT
1073---
1074Part of the linkgit:git[1] suite