1git(1) 2====== 3 4NAME 5---- 6git - the stupid content tracker 7 8 9SYNOPSIS 10-------- 11[verse] 12'git' [--version] [--exec-path[=<path>]] [--html-path] 13 [-p|--paginate|--no-pager] [--no-replace-objects] 14 [--bare] [--git-dir=<path>] [--work-tree=<path>] 15 [-c <name>=<value>] 16 [--help] <command> [<args>] 17 18DESCRIPTION 19----------- 20Git is a fast, scalable, distributed revision control system with an 21unusually rich command set that provides both high-level operations 22and full access to internals. 23 24See linkgit:gittutorial[7] to get started, then see 25link:everyday.html[Everyday Git] for a useful minimum set of commands, and 26"man git-commandname" for documentation of each command. CVS users may 27also want to read linkgit:gitcvs-migration[7]. See 28the link:user-manual.html[Git User's Manual] for a more in-depth 29introduction. 30 31The '<command>' is either a name of a Git command (see below) or an alias 32as defined in the configuration file (see linkgit:git-config[1]). 33 34Formatted and hyperlinked version of the latest git 35documentation can be viewed at 36`http://www.kernel.org/pub/software/scm/git/docs/`. 37 38ifdef::stalenotes[] 39[NOTE] 40============ 41 42You are reading the documentation for the latest (possibly 43unreleased) version of git, that is available from 'master' 44branch of the `git.git` repository. 45Documentation for older releases are available here: 46 47* link:v1.7.3.5/git.html[documentation for release 1.7.3.5] 48 49* release notes for 50 link:RelNotes/1.7.3.5.txt[1.7.3.5], 51 link:RelNotes/1.7.3.4.txt[1.7.3.4], 52 link:RelNotes/1.7.3.3.txt[1.7.3.3], 53 link:RelNotes/1.7.3.2.txt[1.7.3.2], 54 link:RelNotes/1.7.3.1.txt[1.7.3.1], 55 link:RelNotes/1.7.3.txt[1.7.3]. 56 57* link:v1.7.2.5/git.html[documentation for release 1.7.2.5] 58 59* release notes for 60 link:RelNotes/1.7.2.5.txt[1.7.2.5], 61 link:RelNotes/1.7.2.4.txt[1.7.2.4], 62 link:RelNotes/1.7.2.3.txt[1.7.2.3], 63 link:RelNotes/1.7.2.2.txt[1.7.2.2], 64 link:RelNotes/1.7.2.1.txt[1.7.2.1], 65 link:RelNotes/1.7.2.txt[1.7.2]. 66 67* link:v1.7.1.4/git.html[documentation for release 1.7.1.4] 68 69* release notes for 70 link:RelNotes/1.7.1.4.txt[1.7.1.4], 71 link:RelNotes/1.7.1.3.txt[1.7.1.3], 72 link:RelNotes/1.7.1.2.txt[1.7.1.2], 73 link:RelNotes/1.7.1.1.txt[1.7.1.1], 74 link:RelNotes/1.7.1.txt[1.7.1]. 75 76* link:v1.7.0.9/git.html[documentation for release 1.7.0.9] 77 78* release notes for 79 link:RelNotes/1.7.0.9.txt[1.7.0.9], 80 link:RelNotes/1.7.0.8.txt[1.7.0.8], 81 link:RelNotes/1.7.0.7.txt[1.7.0.7], 82 link:RelNotes/1.7.0.6.txt[1.7.0.6], 83 link:RelNotes/1.7.0.5.txt[1.7.0.5], 84 link:RelNotes/1.7.0.4.txt[1.7.0.4], 85 link:RelNotes/1.7.0.3.txt[1.7.0.3], 86 link:RelNotes/1.7.0.2.txt[1.7.0.2], 87 link:RelNotes/1.7.0.1.txt[1.7.0.1], 88 link:RelNotes/1.7.0.txt[1.7.0]. 89 90* link:v1.6.6.3/git.html[documentation for release 1.6.6.3] 91 92* release notes for 93 link:RelNotes/1.6.6.3.txt[1.6.6.3], 94 link:RelNotes/1.6.6.2.txt[1.6.6.2], 95 link:RelNotes/1.6.6.1.txt[1.6.6.1], 96 link:RelNotes/1.6.6.txt[1.6.6]. 97 98* link:v1.6.5.9/git.html[documentation for release 1.6.5.9] 99 100* release notes for 101 link:RelNotes/1.6.5.9.txt[1.6.5.9], 102 link:RelNotes/1.6.5.8.txt[1.6.5.8], 103 link:RelNotes/1.6.5.7.txt[1.6.5.7], 104 link:RelNotes/1.6.5.6.txt[1.6.5.6], 105 link:RelNotes/1.6.5.5.txt[1.6.5.5], 106 link:RelNotes/1.6.5.4.txt[1.6.5.4], 107 link:RelNotes/1.6.5.3.txt[1.6.5.3], 108 link:RelNotes/1.6.5.2.txt[1.6.5.2], 109 link:RelNotes/1.6.5.1.txt[1.6.5.1], 110 link:RelNotes/1.6.5.txt[1.6.5]. 111 112* link:v1.6.4.5/git.html[documentation for release 1.6.4.5] 113 114* release notes for 115 link:RelNotes/1.6.4.5.txt[1.6.4.5], 116 link:RelNotes/1.6.4.4.txt[1.6.4.4], 117 link:RelNotes/1.6.4.3.txt[1.6.4.3], 118 link:RelNotes/1.6.4.2.txt[1.6.4.2], 119 link:RelNotes/1.6.4.1.txt[1.6.4.1], 120 link:RelNotes/1.6.4.txt[1.6.4]. 121 122* link:v1.6.3.4/git.html[documentation for release 1.6.3.4] 123 124* release notes for 125 link:RelNotes/1.6.3.4.txt[1.6.3.4], 126 link:RelNotes/1.6.3.3.txt[1.6.3.3], 127 link:RelNotes/1.6.3.2.txt[1.6.3.2], 128 link:RelNotes/1.6.3.1.txt[1.6.3.1], 129 link:RelNotes/1.6.3.txt[1.6.3]. 130 131* release notes for 132 link:RelNotes/1.6.2.5.txt[1.6.2.5], 133 link:RelNotes/1.6.2.4.txt[1.6.2.4], 134 link:RelNotes/1.6.2.3.txt[1.6.2.3], 135 link:RelNotes/1.6.2.2.txt[1.6.2.2], 136 link:RelNotes/1.6.2.1.txt[1.6.2.1], 137 link:RelNotes/1.6.2.txt[1.6.2]. 138 139* link:v1.6.1.3/git.html[documentation for release 1.6.1.3] 140 141* release notes for 142 link:RelNotes/1.6.1.3.txt[1.6.1.3], 143 link:RelNotes/1.6.1.2.txt[1.6.1.2], 144 link:RelNotes/1.6.1.1.txt[1.6.1.1], 145 link:RelNotes/1.6.1.txt[1.6.1]. 146 147* link:v1.6.0.6/git.html[documentation for release 1.6.0.6] 148 149* release notes for 150 link:RelNotes/1.6.0.6.txt[1.6.0.6], 151 link:RelNotes/1.6.0.5.txt[1.6.0.5], 152 link:RelNotes/1.6.0.4.txt[1.6.0.4], 153 link:RelNotes/1.6.0.3.txt[1.6.0.3], 154 link:RelNotes/1.6.0.2.txt[1.6.0.2], 155 link:RelNotes/1.6.0.1.txt[1.6.0.1], 156 link:RelNotes/1.6.0.txt[1.6.0]. 157 158* link:v1.5.6.6/git.html[documentation for release 1.5.6.6] 159 160* release notes for 161 link:RelNotes/1.5.6.6.txt[1.5.6.6], 162 link:RelNotes/1.5.6.5.txt[1.5.6.5], 163 link:RelNotes/1.5.6.4.txt[1.5.6.4], 164 link:RelNotes/1.5.6.3.txt[1.5.6.3], 165 link:RelNotes/1.5.6.2.txt[1.5.6.2], 166 link:RelNotes/1.5.6.1.txt[1.5.6.1], 167 link:RelNotes/1.5.6.txt[1.5.6]. 168 169* link:v1.5.5.6/git.html[documentation for release 1.5.5.6] 170 171* release notes for 172 link:RelNotes/1.5.5.6.txt[1.5.5.6], 173 link:RelNotes/1.5.5.5.txt[1.5.5.5], 174 link:RelNotes/1.5.5.4.txt[1.5.5.4], 175 link:RelNotes/1.5.5.3.txt[1.5.5.3], 176 link:RelNotes/1.5.5.2.txt[1.5.5.2], 177 link:RelNotes/1.5.5.1.txt[1.5.5.1], 178 link:RelNotes/1.5.5.txt[1.5.5]. 179 180* link:v1.5.4.7/git.html[documentation for release 1.5.4.7] 181 182* release notes for 183 link:RelNotes/1.5.4.7.txt[1.5.4.7], 184 link:RelNotes/1.5.4.6.txt[1.5.4.6], 185 link:RelNotes/1.5.4.5.txt[1.5.4.5], 186 link:RelNotes/1.5.4.4.txt[1.5.4.4], 187 link:RelNotes/1.5.4.3.txt[1.5.4.3], 188 link:RelNotes/1.5.4.2.txt[1.5.4.2], 189 link:RelNotes/1.5.4.1.txt[1.5.4.1], 190 link:RelNotes/1.5.4.txt[1.5.4]. 191 192* link:v1.5.3.8/git.html[documentation for release 1.5.3.8] 193 194* release notes for 195 link:RelNotes/1.5.3.8.txt[1.5.3.8], 196 link:RelNotes/1.5.3.7.txt[1.5.3.7], 197 link:RelNotes/1.5.3.6.txt[1.5.3.6], 198 link:RelNotes/1.5.3.5.txt[1.5.3.5], 199 link:RelNotes/1.5.3.4.txt[1.5.3.4], 200 link:RelNotes/1.5.3.3.txt[1.5.3.3], 201 link:RelNotes/1.5.3.2.txt[1.5.3.2], 202 link:RelNotes/1.5.3.1.txt[1.5.3.1], 203 link:RelNotes/1.5.3.txt[1.5.3]. 204 205* link:v1.5.2.5/git.html[documentation for release 1.5.2.5] 206 207* release notes for 208 link:RelNotes/1.5.2.5.txt[1.5.2.5], 209 link:RelNotes/1.5.2.4.txt[1.5.2.4], 210 link:RelNotes/1.5.2.3.txt[1.5.2.3], 211 link:RelNotes/1.5.2.2.txt[1.5.2.2], 212 link:RelNotes/1.5.2.1.txt[1.5.2.1], 213 link:RelNotes/1.5.2.txt[1.5.2]. 214 215* link:v1.5.1.6/git.html[documentation for release 1.5.1.6] 216 217* release notes for 218 link:RelNotes/1.5.1.6.txt[1.5.1.6], 219 link:RelNotes/1.5.1.5.txt[1.5.1.5], 220 link:RelNotes/1.5.1.4.txt[1.5.1.4], 221 link:RelNotes/1.5.1.3.txt[1.5.1.3], 222 link:RelNotes/1.5.1.2.txt[1.5.1.2], 223 link:RelNotes/1.5.1.1.txt[1.5.1.1], 224 link:RelNotes/1.5.1.txt[1.5.1]. 225 226* link:v1.5.0.7/git.html[documentation for release 1.5.0.7] 227 228* release notes for 229 link:RelNotes/1.5.0.7.txt[1.5.0.7], 230 link:RelNotes/1.5.0.6.txt[1.5.0.6], 231 link:RelNotes/1.5.0.5.txt[1.5.0.5], 232 link:RelNotes/1.5.0.3.txt[1.5.0.3], 233 link:RelNotes/1.5.0.2.txt[1.5.0.2], 234 link:RelNotes/1.5.0.1.txt[1.5.0.1], 235 link:RelNotes/1.5.0.txt[1.5.0]. 236 237* documentation for release link:v1.4.4.4/git.html[1.4.4.4], 238 link:v1.3.3/git.html[1.3.3], 239 link:v1.2.6/git.html[1.2.6], 240 link:v1.0.13/git.html[1.0.13]. 241 242============ 243 244endif::stalenotes[] 245 246OPTIONS 247------- 248--version:: 249 Prints the git suite version that the 'git' program came from. 250 251--help:: 252 Prints the synopsis and a list of the most commonly used 253 commands. If the option '--all' or '-a' is given then all 254 available commands are printed. If a git command is named this 255 option will bring up the manual page for that command. 256+ 257Other options are available to control how the manual page is 258displayed. See linkgit:git-help[1] for more information, 259because `git --help ...` is converted internally into `git 260help ...`. 261 262-c <name>=<value>:: 263 Pass a configuration parameter to the command. The value 264 given will override values from configuration files. 265 The <name> is expected in the same format as listed by 266 'git config' (subkeys separated by dots). 267 268--exec-path[=<path>]:: 269 Path to wherever your core git programs are installed. 270 This can also be controlled by setting the GIT_EXEC_PATH 271 environment variable. If no path is given, 'git' will print 272 the current setting and then exit. 273 274--html-path:: 275 Print the path to wherever your git HTML documentation is installed 276 and exit. 277 278-p:: 279--paginate:: 280 Pipe all output into 'less' (or if set, $PAGER) if standard 281 output is a terminal. This overrides the `pager.<cmd>` 282 configuration options (see the "Configuration Mechanism" section 283 below). 284 285--no-pager:: 286 Do not pipe git output into a pager. 287 288--git-dir=<path>:: 289 Set the path to the repository. This can also be controlled by 290 setting the GIT_DIR environment variable. It can be an absolute 291 path or relative path to current working directory. 292 293--work-tree=<path>:: 294 Set the path to the working tree. It can be an absolute path 295 or a path relative to the current working directory. 296 This can also be controlled by setting the GIT_WORK_TREE 297 environment variable and the core.worktree configuration 298 variable (see core.worktree in linkgit:git-config[1] for a 299 more detailed discussion). 300 301--bare:: 302 Treat the repository as a bare repository. If GIT_DIR 303 environment is not set, it is set to the current working 304 directory. 305 306--no-replace-objects:: 307 Do not use replacement refs to replace git objects. See 308 linkgit:git-replace[1] for more information. 309 310 311FURTHER DOCUMENTATION 312--------------------- 313 314See the references above to get started using git. The following is 315probably more detail than necessary for a first-time user. 316 317The link:user-manual.html#git-concepts[git concepts chapter of the 318user-manual] and linkgit:gitcore-tutorial[7] both provide 319introductions to the underlying git architecture. 320 321See linkgit:gitworkflows[7] for an overview of recommended workflows. 322 323See also the link:howto-index.html[howto] documents for some useful 324examples. 325 326The internals are documented in the 327link:technical/api-index.html[GIT API documentation]. 328 329GIT COMMANDS 330------------ 331 332We divide git into high level ("porcelain") commands and low level 333("plumbing") commands. 334 335High-level commands (porcelain) 336------------------------------- 337 338We separate the porcelain commands into the main commands and some 339ancillary user utilities. 340 341Main porcelain commands 342~~~~~~~~~~~~~~~~~~~~~~~ 343 344include::cmds-mainporcelain.txt[] 345 346Ancillary Commands 347~~~~~~~~~~~~~~~~~~ 348Manipulators: 349 350include::cmds-ancillarymanipulators.txt[] 351 352Interrogators: 353 354include::cmds-ancillaryinterrogators.txt[] 355 356 357Interacting with Others 358~~~~~~~~~~~~~~~~~~~~~~~ 359 360These commands are to interact with foreign SCM and with other 361people via patch over e-mail. 362 363include::cmds-foreignscminterface.txt[] 364 365 366Low-level commands (plumbing) 367----------------------------- 368 369Although git includes its 370own porcelain layer, its low-level commands are sufficient to support 371development of alternative porcelains. Developers of such porcelains 372might start by reading about linkgit:git-update-index[1] and 373linkgit:git-read-tree[1]. 374 375The interface (input, output, set of options and the semantics) 376to these low-level commands are meant to be a lot more stable 377than Porcelain level commands, because these commands are 378primarily for scripted use. The interface to Porcelain commands 379on the other hand are subject to change in order to improve the 380end user experience. 381 382The following description divides 383the low-level commands into commands that manipulate objects (in 384the repository, index, and working tree), commands that interrogate and 385compare objects, and commands that move objects and references between 386repositories. 387 388 389Manipulation commands 390~~~~~~~~~~~~~~~~~~~~~ 391 392include::cmds-plumbingmanipulators.txt[] 393 394 395Interrogation commands 396~~~~~~~~~~~~~~~~~~~~~~ 397 398include::cmds-plumbinginterrogators.txt[] 399 400In general, the interrogate commands do not touch the files in 401the working tree. 402 403 404Synching repositories 405~~~~~~~~~~~~~~~~~~~~~ 406 407include::cmds-synchingrepositories.txt[] 408 409The following are helper commands used by the above; end users 410typically do not use them directly. 411 412include::cmds-synchelpers.txt[] 413 414 415Internal helper commands 416~~~~~~~~~~~~~~~~~~~~~~~~ 417 418These are internal helper commands used by other commands; end 419users typically do not use them directly. 420 421include::cmds-purehelpers.txt[] 422 423 424Configuration Mechanism 425----------------------- 426 427Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file 428is used to hold per-repository configuration options. It is a 429simple text file modeled after `.ini` format familiar to some 430people. Here is an example: 431 432------------ 433# 434# A '#' or ';' character indicates a comment. 435# 436 437; core variables 438[core] 439 ; Don't trust file modes 440 filemode = false 441 442; user identity 443[user] 444 name = "Junio C Hamano" 445 email = "junkio@twinsun.com" 446 447------------ 448 449Various commands read from the configuration file and adjust 450their operation accordingly. See linkgit:git-config[1] for a 451list. 452 453 454Identifier Terminology 455---------------------- 456<object>:: 457 Indicates the object name for any type of object. 458 459<blob>:: 460 Indicates a blob object name. 461 462<tree>:: 463 Indicates a tree object name. 464 465<commit>:: 466 Indicates a commit object name. 467 468<tree-ish>:: 469 Indicates a tree, commit or tag object name. A 470 command that takes a <tree-ish> argument ultimately wants to 471 operate on a <tree> object but automatically dereferences 472 <commit> and <tag> objects that point at a <tree>. 473 474<commit-ish>:: 475 Indicates a commit or tag object name. A 476 command that takes a <commit-ish> argument ultimately wants to 477 operate on a <commit> object but automatically dereferences 478 <tag> objects that point at a <commit>. 479 480<type>:: 481 Indicates that an object type is required. 482 Currently one of: `blob`, `tree`, `commit`, or `tag`. 483 484<file>:: 485 Indicates a filename - almost always relative to the 486 root of the tree structure `GIT_INDEX_FILE` describes. 487 488Symbolic Identifiers 489-------------------- 490Any git command accepting any <object> can also use the following 491symbolic notation: 492 493HEAD:: 494 indicates the head of the current branch (i.e. the 495 contents of `$GIT_DIR/HEAD`). 496 497<tag>:: 498 a valid tag 'name' 499 (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`). 500 501<head>:: 502 a valid head 'name' 503 (i.e. the contents of `$GIT_DIR/refs/heads/<head>`). 504 505For a more complete list of ways to spell object names, see 506"SPECIFYING REVISIONS" section in linkgit:gitrevisions[7]. 507 508 509File/Directory Structure 510------------------------ 511 512Please see the linkgit:gitrepository-layout[5] document. 513 514Read linkgit:githooks[5] for more details about each hook. 515 516Higher level SCMs may provide and manage additional information in the 517`$GIT_DIR`. 518 519 520Terminology 521----------- 522Please see linkgit:gitglossary[7]. 523 524 525Environment Variables 526--------------------- 527Various git commands use the following environment variables: 528 529The git Repository 530~~~~~~~~~~~~~~~~~~ 531These environment variables apply to 'all' core git commands. Nb: it 532is worth noting that they may be used/overridden by SCMS sitting above 533git so take care if using Cogito etc. 534 535'GIT_INDEX_FILE':: 536 This environment allows the specification of an alternate 537 index file. If not specified, the default of `$GIT_DIR/index` 538 is used. 539 540'GIT_OBJECT_DIRECTORY':: 541 If the object storage directory is specified via this 542 environment variable then the sha1 directories are created 543 underneath - otherwise the default `$GIT_DIR/objects` 544 directory is used. 545 546'GIT_ALTERNATE_OBJECT_DIRECTORIES':: 547 Due to the immutable nature of git objects, old objects can be 548 archived into shared, read-only directories. This variable 549 specifies a ":" separated (on Windows ";" separated) list 550 of git object directories which can be used to search for git 551 objects. New objects will not be written to these directories. 552 553'GIT_DIR':: 554 If the 'GIT_DIR' environment variable is set then it 555 specifies a path to use instead of the default `.git` 556 for the base of the repository. 557 558'GIT_WORK_TREE':: 559 Set the path to the working tree. The value will not be 560 used in combination with repositories found automatically in 561 a .git directory (i.e. $GIT_DIR is not set). 562 This can also be controlled by the '--work-tree' command line 563 option and the core.worktree configuration variable. 564 565'GIT_CEILING_DIRECTORIES':: 566 This should be a colon-separated list of absolute paths. 567 If set, it is a list of directories that git should not chdir 568 up into while looking for a repository directory. 569 It will not exclude the current working directory or 570 a GIT_DIR set on the command line or in the environment. 571 (Useful for excluding slow-loading network directories.) 572 573'GIT_DISCOVERY_ACROSS_FILESYSTEM':: 574 When run in a directory that does not have ".git" repository 575 directory, git tries to find such a directory in the parent 576 directories to find the top of the working tree, but by default it 577 does not cross filesystem boundaries. This environment variable 578 can be set to true to tell git not to stop at filesystem 579 boundaries. Like 'GIT_CEILING_DIRECTORIES', this will not affect 580 an explicit repository directory set via 'GIT_DIR' or on the 581 command line. 582 583git Commits 584~~~~~~~~~~~ 585'GIT_AUTHOR_NAME':: 586'GIT_AUTHOR_EMAIL':: 587'GIT_AUTHOR_DATE':: 588'GIT_COMMITTER_NAME':: 589'GIT_COMMITTER_EMAIL':: 590'GIT_COMMITTER_DATE':: 591'EMAIL':: 592 see linkgit:git-commit-tree[1] 593 594git Diffs 595~~~~~~~~~ 596'GIT_DIFF_OPTS':: 597 Only valid setting is "--unified=??" or "-u??" to set the 598 number of context lines shown when a unified diff is created. 599 This takes precedence over any "-U" or "--unified" option 600 value passed on the git diff command line. 601 602'GIT_EXTERNAL_DIFF':: 603 When the environment variable 'GIT_EXTERNAL_DIFF' is set, the 604 program named by it is called, instead of the diff invocation 605 described above. For a path that is added, removed, or modified, 606 'GIT_EXTERNAL_DIFF' is called with 7 parameters: 607 608 path old-file old-hex old-mode new-file new-hex new-mode 609+ 610where: 611 612 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the 613 contents of <old|new>, 614 <old|new>-hex:: are the 40-hexdigit SHA1 hashes, 615 <old|new>-mode:: are the octal representation of the file modes. 616 617+ 618The file parameters can point at the user's working file 619(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file` 620when a new file is added), or a temporary file (e.g. `old-file` in the 621index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the 622temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits. 623+ 624For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1 625parameter, <path>. 626 627other 628~~~~~ 629'GIT_MERGE_VERBOSITY':: 630 A number controlling the amount of output shown by 631 the recursive merge strategy. Overrides merge.verbosity. 632 See linkgit:git-merge[1] 633 634'GIT_PAGER':: 635 This environment variable overrides `$PAGER`. If it is set 636 to an empty string or to the value "cat", git will not launch 637 a pager. See also the `core.pager` option in 638 linkgit:git-config[1]. 639 640'GIT_SSH':: 641 If this environment variable is set then 'git fetch' 642 and 'git push' will use this command instead 643 of 'ssh' when they need to connect to a remote system. 644 The '$GIT_SSH' command will be given exactly two arguments: 645 the 'username@host' (or just 'host') from the URL and the 646 shell command to execute on that remote system. 647+ 648To pass options to the program that you want to list in GIT_SSH 649you will need to wrap the program and options into a shell script, 650then set GIT_SSH to refer to the shell script. 651+ 652Usually it is easier to configure any desired options through your 653personal `.ssh/config` file. Please consult your ssh documentation 654for further details. 655 656'GIT_ASKPASS':: 657 If this environment variable is set, then git commands which need to 658 acquire passwords or passphrases (e.g. for HTTP or IMAP authentication) 659 will call this program with a suitable prompt as command line argument 660 and read the password from its STDOUT. See also the 'core.askpass' 661 option in linkgit:git-config[1]. 662 663'GIT_FLUSH':: 664 If this environment variable is set to "1", then commands such 665 as 'git blame' (in incremental mode), 'git rev-list', 'git log', 666 and 'git whatchanged' will force a flush of the output stream 667 after each commit-oriented record have been flushed. If this 668 variable is set to "0", the output of these commands will be done 669 using completely buffered I/O. If this environment variable is 670 not set, git will choose buffered or record-oriented flushing 671 based on whether stdout appears to be redirected to a file or not. 672 673'GIT_TRACE':: 674 If this variable is set to "1", "2" or "true" (comparison 675 is case insensitive), git will print `trace:` messages on 676 stderr telling about alias expansion, built-in command 677 execution and external command execution. 678 If this variable is set to an integer value greater than 1 679 and lower than 10 (strictly) then git will interpret this 680 value as an open file descriptor and will try to write the 681 trace messages into this file descriptor. 682 Alternatively, if this variable is set to an absolute path 683 (starting with a '/' character), git will interpret this 684 as a file path and will try to write the trace messages 685 into it. 686 687Discussion[[Discussion]] 688------------------------ 689 690More detail on the following is available from the 691link:user-manual.html#git-concepts[git concepts chapter of the 692user-manual] and linkgit:gitcore-tutorial[7]. 693 694A git project normally consists of a working directory with a ".git" 695subdirectory at the top level. The .git directory contains, among other 696things, a compressed object database representing the complete history 697of the project, an "index" file which links that history to the current 698contents of the working tree, and named pointers into that history such 699as tags and branch heads. 700 701The object database contains objects of three main types: blobs, which 702hold file data; trees, which point to blobs and other trees to build up 703directory hierarchies; and commits, which each reference a single tree 704and some number of parent commits. 705 706The commit, equivalent to what other systems call a "changeset" or 707"version", represents a step in the project's history, and each parent 708represents an immediately preceding step. Commits with more than one 709parent represent merges of independent lines of development. 710 711All objects are named by the SHA1 hash of their contents, normally 712written as a string of 40 hex digits. Such names are globally unique. 713The entire history leading up to a commit can be vouched for by signing 714just that commit. A fourth object type, the tag, is provided for this 715purpose. 716 717When first created, objects are stored in individual files, but for 718efficiency may later be compressed together into "pack files". 719 720Named pointers called refs mark interesting points in history. A ref 721may contain the SHA1 name of an object or the name of another ref. Refs 722with names beginning `ref/head/` contain the SHA1 name of the most 723recent commit (or "head") of a branch under development. SHA1 names of 724tags of interest are stored under `ref/tags/`. A special ref named 725`HEAD` contains the name of the currently checked-out branch. 726 727The index file is initialized with a list of all paths and, for each 728path, a blob object and a set of attributes. The blob object represents 729the contents of the file as of the head of the current branch. The 730attributes (last modified time, size, etc.) are taken from the 731corresponding file in the working tree. Subsequent changes to the 732working tree can be found by comparing these attributes. The index may 733be updated with new content, and new commits may be created from the 734content stored in the index. 735 736The index is also capable of storing multiple entries (called "stages") 737for a given pathname. These stages are used to hold the various 738unmerged version of a file when a merge is in progress. 739 740Authors 741------- 742* git's founding father is Linus Torvalds <torvalds@osdl.org>. 743* The current git nurse is Junio C Hamano <gitster@pobox.com>. 744* The git potty was written by Andreas Ericsson <ae@op5.se>. 745* General upbringing is handled by the git-list <git@vger.kernel.org>. 746 747Documentation 748-------------- 749The documentation for git suite was started by David Greaves 750<david@dgreaves.com>, and later enhanced greatly by the 751contributors on the git-list <git@vger.kernel.org>. 752 753Reporting Bugs 754-------------- 755 756Report bugs to the Git mailing list <git@vger.kernel.org> where the 757development and maintenance is primarily done. You do not have to be 758subscribed to the list to send a message there. 759 760SEE ALSO 761-------- 762linkgit:gittutorial[7], linkgit:gittutorial-2[7], 763link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7], 764linkgit:gitglossary[7], linkgit:gitcore-tutorial[7], 765linkgit:gitcli[7], link:user-manual.html[The Git User's Manual], 766linkgit:gitworkflows[7] 767 768GIT 769--- 770Part of the linkgit:git[1] suite