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