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