Documentation/git.txt

   1 git(1)
   2 ======
   3
   4 NAME
   5 ----
   6 git - the stupid content tracker
   7
   8
   9 SYNOPSIS
  10 --------
  11 [verse]
  12 'git' [--version] [--help] [-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     <command> [<args>]
  17
  18 DESCRIPTION
  19 -----------
  20 Git is a fast, scalable, distributed revision control system with an
  21 unusually rich command set that provides both high-level operations
  22 and full access to internals.
  23
  24 See linkgit:gittutorial[7] to get started, then see
  25 link:everyday.html[Everyday Git] for a useful minimum set of commands, and
  26 "man git-commandname" for documentation of each command.  CVS users may
  27 also want to read linkgit:gitcvs-migration[7].  See
  28 the link:user-manual.html[Git User's Manual] for a more in-depth
  29 introduction.
  30
  31 The '<command>' is either a name of a Git command (see below) or an alias
  32 as defined in the configuration file (see linkgit:git-config[1]).
  33
  34 Formatted and hyperlinked version of the latest git
  35 documentation can be viewed at
  36 `http://www.kernel.org/pub/software/scm/git/docs/`.
  37
  38 ifdef::stalenotes[]
  39 [NOTE]
  40 ============
  41
  42 You are reading the documentation for the latest (possibly
  43 unreleased) version of git, that is available from 'master'
  44 branch of the `git.git` repository.
  45 Documentation for older releases are available here:
  46
  47 * link:v1.7.9.4/git.html[documentation for release 1.7.9.4]
  48
  49 * release notes for
  50   link:RelNotes/1.7.9.4.txt[1.7.9.4],
  51   link:RelNotes/1.7.9.3.txt[1.7.9.3],
  52   link:RelNotes/1.7.9.2.txt[1.7.9.2],
  53   link:RelNotes/1.7.9.1.txt[1.7.9.1],
  54   link:RelNotes/1.7.9.txt[1.7.9].
  55
  56 * link:v1.7.8.4/git.html[documentation for release 1.7.8.4]
  57
  58 * release notes for
  59   link:RelNotes/1.7.8.4.txt[1.7.8.4],
  60   link:RelNotes/1.7.8.3.txt[1.7.8.3],
  61   link:RelNotes/1.7.8.2.txt[1.7.8.2],
  62   link:RelNotes/1.7.8.1.txt[1.7.8.1],
  63   link:RelNotes/1.7.8.txt[1.7.8].
  64
  65 * link:v1.7.7.6/git.html[documentation for release 1.7.7.6]
  66
  67 * release notes for
  68   link:RelNotes/1.7.7.6.txt[1.7.7.6],
  69   link:RelNotes/1.7.7.5.txt[1.7.7.5],
  70   link:RelNotes/1.7.7.4.txt[1.7.7.4],
  71   link:RelNotes/1.7.7.3.txt[1.7.7.3],
  72   link:RelNotes/1.7.7.2.txt[1.7.7.2],
  73   link:RelNotes/1.7.7.1.txt[1.7.7.1],
  74   link:RelNotes/1.7.7.txt[1.7.7].
  75
  76 * link:v1.7.6.6/git.html[documentation for release 1.7.6.6]
  77
  78 * release notes for
  79   link:RelNotes/1.7.6.6.txt[1.7.6.6],
  80   link:RelNotes/1.7.6.5.txt[1.7.6.5],
  81   link:RelNotes/1.7.6.4.txt[1.7.6.4],
  82   link:RelNotes/1.7.6.3.txt[1.7.6.3],
  83   link:RelNotes/1.7.6.2.txt[1.7.6.2],
  84   link:RelNotes/1.7.6.1.txt[1.7.6.1],
  85   link:RelNotes/1.7.6.txt[1.7.6].
  86
  87 * link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
  88
  89 * release notes for
  90   link:RelNotes/1.7.5.4.txt[1.7.5.4],
  91   link:RelNotes/1.7.5.3.txt[1.7.5.3],
  92   link:RelNotes/1.7.5.2.txt[1.7.5.2],
  93   link:RelNotes/1.7.5.1.txt[1.7.5.1],
  94   link:RelNotes/1.7.5.txt[1.7.5].
  95
  96 * link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
  97
  98 * release notes for
  99   link:RelNotes/1.7.4.5.txt[1.7.4.5],
 100   link:RelNotes/1.7.4.4.txt[1.7.4.4],
 101   link:RelNotes/1.7.4.3.txt[1.7.4.3],
 102   link:RelNotes/1.7.4.2.txt[1.7.4.2],
 103   link:RelNotes/1.7.4.1.txt[1.7.4.1],
 104   link:RelNotes/1.7.4.txt[1.7.4].
 105
 106 * link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
 107
 108 * release notes for
 109   link:RelNotes/1.7.3.5.txt[1.7.3.5],
 110   link:RelNotes/1.7.3.4.txt[1.7.3.4],
 111   link:RelNotes/1.7.3.3.txt[1.7.3.3],
 112   link:RelNotes/1.7.3.2.txt[1.7.3.2],
 113   link:RelNotes/1.7.3.1.txt[1.7.3.1],
 114   link:RelNotes/1.7.3.txt[1.7.3].
 115
 116 * link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
 117
 118 * release notes for
 119   link:RelNotes/1.7.2.5.txt[1.7.2.5],
 120   link:RelNotes/1.7.2.4.txt[1.7.2.4],
 121   link:RelNotes/1.7.2.3.txt[1.7.2.3],
 122   link:RelNotes/1.7.2.2.txt[1.7.2.2],
 123   link:RelNotes/1.7.2.1.txt[1.7.2.1],
 124   link:RelNotes/1.7.2.txt[1.7.2].
 125
 126 * link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
 127
 128 * release notes for
 129   link:RelNotes/1.7.1.4.txt[1.7.1.4],
 130   link:RelNotes/1.7.1.3.txt[1.7.1.3],
 131   link:RelNotes/1.7.1.2.txt[1.7.1.2],
 132   link:RelNotes/1.7.1.1.txt[1.7.1.1],
 133   link:RelNotes/1.7.1.txt[1.7.1].
 134
 135 * link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
 136
 137 * release notes for
 138   link:RelNotes/1.7.0.9.txt[1.7.0.9],
 139   link:RelNotes/1.7.0.8.txt[1.7.0.8],
 140   link:RelNotes/1.7.0.7.txt[1.7.0.7],
 141   link:RelNotes/1.7.0.6.txt[1.7.0.6],
 142   link:RelNotes/1.7.0.5.txt[1.7.0.5],
 143   link:RelNotes/1.7.0.4.txt[1.7.0.4],
 144   link:RelNotes/1.7.0.3.txt[1.7.0.3],
 145   link:RelNotes/1.7.0.2.txt[1.7.0.2],
 146   link:RelNotes/1.7.0.1.txt[1.7.0.1],
 147   link:RelNotes/1.7.0.txt[1.7.0].
 148
 149 * link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
 150
 151 * release notes for
 152   link:RelNotes/1.6.6.3.txt[1.6.6.3],
 153   link:RelNotes/1.6.6.2.txt[1.6.6.2],
 154   link:RelNotes/1.6.6.1.txt[1.6.6.1],
 155   link:RelNotes/1.6.6.txt[1.6.6].
 156
 157 * link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
 158
 159 * release notes for
 160   link:RelNotes/1.6.5.9.txt[1.6.5.9],
 161   link:RelNotes/1.6.5.8.txt[1.6.5.8],
 162   link:RelNotes/1.6.5.7.txt[1.6.5.7],
 163   link:RelNotes/1.6.5.6.txt[1.6.5.6],
 164   link:RelNotes/1.6.5.5.txt[1.6.5.5],
 165   link:RelNotes/1.6.5.4.txt[1.6.5.4],
 166   link:RelNotes/1.6.5.3.txt[1.6.5.3],
 167   link:RelNotes/1.6.5.2.txt[1.6.5.2],
 168   link:RelNotes/1.6.5.1.txt[1.6.5.1],
 169   link:RelNotes/1.6.5.txt[1.6.5].
 170
 171 * link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
 172
 173 * release notes for
 174   link:RelNotes/1.6.4.5.txt[1.6.4.5],
 175   link:RelNotes/1.6.4.4.txt[1.6.4.4],
 176   link:RelNotes/1.6.4.3.txt[1.6.4.3],
 177   link:RelNotes/1.6.4.2.txt[1.6.4.2],
 178   link:RelNotes/1.6.4.1.txt[1.6.4.1],
 179   link:RelNotes/1.6.4.txt[1.6.4].
 180
 181 * link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
 182
 183 * release notes for
 184   link:RelNotes/1.6.3.4.txt[1.6.3.4],
 185   link:RelNotes/1.6.3.3.txt[1.6.3.3],
 186   link:RelNotes/1.6.3.2.txt[1.6.3.2],
 187   link:RelNotes/1.6.3.1.txt[1.6.3.1],
 188   link:RelNotes/1.6.3.txt[1.6.3].
 189
 190 * release notes for
 191   link:RelNotes/1.6.2.5.txt[1.6.2.5],
 192   link:RelNotes/1.6.2.4.txt[1.6.2.4],
 193   link:RelNotes/1.6.2.3.txt[1.6.2.3],
 194   link:RelNotes/1.6.2.2.txt[1.6.2.2],
 195   link:RelNotes/1.6.2.1.txt[1.6.2.1],
 196   link:RelNotes/1.6.2.txt[1.6.2].
 197
 198 * link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
 199
 200 * release notes for
 201   link:RelNotes/1.6.1.3.txt[1.6.1.3],
 202   link:RelNotes/1.6.1.2.txt[1.6.1.2],
 203   link:RelNotes/1.6.1.1.txt[1.6.1.1],
 204   link:RelNotes/1.6.1.txt[1.6.1].
 205
 206 * link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
 207
 208 * release notes for
 209   link:RelNotes/1.6.0.6.txt[1.6.0.6],
 210   link:RelNotes/1.6.0.5.txt[1.6.0.5],
 211   link:RelNotes/1.6.0.4.txt[1.6.0.4],
 212   link:RelNotes/1.6.0.3.txt[1.6.0.3],
 213   link:RelNotes/1.6.0.2.txt[1.6.0.2],
 214   link:RelNotes/1.6.0.1.txt[1.6.0.1],
 215   link:RelNotes/1.6.0.txt[1.6.0].
 216
 217 * link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
 218
 219 * release notes for
 220   link:RelNotes/1.5.6.6.txt[1.5.6.6],
 221   link:RelNotes/1.5.6.5.txt[1.5.6.5],
 222   link:RelNotes/1.5.6.4.txt[1.5.6.4],
 223   link:RelNotes/1.5.6.3.txt[1.5.6.3],
 224   link:RelNotes/1.5.6.2.txt[1.5.6.2],
 225   link:RelNotes/1.5.6.1.txt[1.5.6.1],
 226   link:RelNotes/1.5.6.txt[1.5.6].
 227
 228 * link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
 229
 230 * release notes for
 231   link:RelNotes/1.5.5.6.txt[1.5.5.6],
 232   link:RelNotes/1.5.5.5.txt[1.5.5.5],
 233   link:RelNotes/1.5.5.4.txt[1.5.5.4],
 234   link:RelNotes/1.5.5.3.txt[1.5.5.3],
 235   link:RelNotes/1.5.5.2.txt[1.5.5.2],
 236   link:RelNotes/1.5.5.1.txt[1.5.5.1],
 237   link:RelNotes/1.5.5.txt[1.5.5].
 238
 239 * link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
 240
 241 * release notes for
 242   link:RelNotes/1.5.4.7.txt[1.5.4.7],
 243   link:RelNotes/1.5.4.6.txt[1.5.4.6],
 244   link:RelNotes/1.5.4.5.txt[1.5.4.5],
 245   link:RelNotes/1.5.4.4.txt[1.5.4.4],
 246   link:RelNotes/1.5.4.3.txt[1.5.4.3],
 247   link:RelNotes/1.5.4.2.txt[1.5.4.2],
 248   link:RelNotes/1.5.4.1.txt[1.5.4.1],
 249   link:RelNotes/1.5.4.txt[1.5.4].
 250
 251 * link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
 252
 253 * release notes for
 254   link:RelNotes/1.5.3.8.txt[1.5.3.8],
 255   link:RelNotes/1.5.3.7.txt[1.5.3.7],
 256   link:RelNotes/1.5.3.6.txt[1.5.3.6],
 257   link:RelNotes/1.5.3.5.txt[1.5.3.5],
 258   link:RelNotes/1.5.3.4.txt[1.5.3.4],
 259   link:RelNotes/1.5.3.3.txt[1.5.3.3],
 260   link:RelNotes/1.5.3.2.txt[1.5.3.2],
 261   link:RelNotes/1.5.3.1.txt[1.5.3.1],
 262   link:RelNotes/1.5.3.txt[1.5.3].
 263
 264 * link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
 265
 266 * release notes for
 267   link:RelNotes/1.5.2.5.txt[1.5.2.5],
 268   link:RelNotes/1.5.2.4.txt[1.5.2.4],
 269   link:RelNotes/1.5.2.3.txt[1.5.2.3],
 270   link:RelNotes/1.5.2.2.txt[1.5.2.2],
 271   link:RelNotes/1.5.2.1.txt[1.5.2.1],
 272   link:RelNotes/1.5.2.txt[1.5.2].
 273
 274 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
 275
 276 * release notes for
 277   link:RelNotes/1.5.1.6.txt[1.5.1.6],
 278   link:RelNotes/1.5.1.5.txt[1.5.1.5],
 279   link:RelNotes/1.5.1.4.txt[1.5.1.4],
 280   link:RelNotes/1.5.1.3.txt[1.5.1.3],
 281   link:RelNotes/1.5.1.2.txt[1.5.1.2],
 282   link:RelNotes/1.5.1.1.txt[1.5.1.1],
 283   link:RelNotes/1.5.1.txt[1.5.1].
 284
 285 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
 286
 287 * release notes for
 288   link:RelNotes/1.5.0.7.txt[1.5.0.7],
 289   link:RelNotes/1.5.0.6.txt[1.5.0.6],
 290   link:RelNotes/1.5.0.5.txt[1.5.0.5],
 291   link:RelNotes/1.5.0.3.txt[1.5.0.3],
 292   link:RelNotes/1.5.0.2.txt[1.5.0.2],
 293   link:RelNotes/1.5.0.1.txt[1.5.0.1],
 294   link:RelNotes/1.5.0.txt[1.5.0].
 295
 296 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 297   link:v1.3.3/git.html[1.3.3],
 298   link:v1.2.6/git.html[1.2.6],
 299   link:v1.0.13/git.html[1.0.13].
 300
 301 ============
 302
 303 endif::stalenotes[]
 304
 305 OPTIONS
 306 -------
 307 --version::
 308         Prints the git suite version that the 'git' program came from.
 309
 310 --help::
 311         Prints the synopsis and a list of the most commonly used
 312         commands. If the option '--all' or '-a' is given then all
 313         available commands are printed. If a git command is named this
 314         option will bring up the manual page for that command.
 315 +
 316 Other options are available to control how the manual page is
 317 displayed. See linkgit:git-help[1] for more information,
 318 because `git --help ...` is converted internally into `git
 319 help ...`.
 320
 321 -c <name>=<value>::
 322         Pass a configuration parameter to the command. The value
 323         given will override values from configuration files.
 324         The <name> is expected in the same format as listed by
 325         'git config' (subkeys separated by dots).
 326
 327 --exec-path[=<path>]::
 328         Path to wherever your core git programs are installed.
 329         This can also be controlled by setting the GIT_EXEC_PATH
 330         environment variable. If no path is given, 'git' will print
 331         the current setting and then exit.
 332
 333 --html-path::
 334         Print the path, without trailing slash, where git's HTML
 335         documentation is installed and exit.
 336
 337 --man-path::
 338         Print the manpath (see `man(1)`) for the man pages for
 339         this version of git and exit.
 340
 341 --info-path::
 342         Print the path where the Info files documenting this
 343         version of git are installed and exit.
 344
 345 -p::
 346 --paginate::
 347         Pipe all output into 'less' (or if set, $PAGER) if standard
 348         output is a terminal.  This overrides the `pager.<cmd>`
 349         configuration options (see the "Configuration Mechanism" section
 350         below).
 351
 352 --no-pager::
 353         Do not pipe git output into a pager.
 354
 355 --git-dir=<path>::
 356         Set the path to the repository. This can also be controlled by
 357         setting the GIT_DIR environment variable. It can be an absolute
 358         path or relative path to current working directory.
 359
 360 --work-tree=<path>::
 361         Set the path to the working tree. It can be an absolute path
 362         or a path relative to the current working directory.
 363         This can also be controlled by setting the GIT_WORK_TREE
 364         environment variable and the core.worktree configuration
 365         variable (see core.worktree in linkgit:git-config[1] for a
 366         more detailed discussion).
 367
 368 --namespace=<path>::
 369         Set the git namespace.  See linkgit:gitnamespaces[7] for more
 370         details.  Equivalent to setting the `GIT_NAMESPACE` environment
 371         variable.
 372
 373 --bare::
 374         Treat the repository as a bare repository.  If GIT_DIR
 375         environment is not set, it is set to the current working
 376         directory.
 377
 378 --no-replace-objects::
 379         Do not use replacement refs to replace git objects. See
 380         linkgit:git-replace[1] for more information.
 381
 382
 383 FURTHER DOCUMENTATION
 384 ---------------------
 385
 386 See the references above to get started using git.  The following is
 387 probably more detail than necessary for a first-time user.
 388
 389 The link:user-manual.html#git-concepts[git concepts chapter of the
 390 user-manual] and linkgit:gitcore-tutorial[7] both provide
 391 introductions to the underlying git architecture.
 392
 393 See linkgit:gitworkflows[7] for an overview of recommended workflows.
 394
 395 See also the link:howto-index.html[howto] documents for some useful
 396 examples.
 397
 398 The internals are documented in the
 399 link:technical/api-index.html[GIT API documentation].
 400
 401 GIT COMMANDS
 402 ------------
 403
 404 We divide git into high level ("porcelain") commands and low level
 405 ("plumbing") commands.
 406
 407 High-level commands (porcelain)
 408 -------------------------------
 409
 410 We separate the porcelain commands into the main commands and some
 411 ancillary user utilities.
 412
 413 Main porcelain commands
 414 ~~~~~~~~~~~~~~~~~~~~~~~
 415
 416 include::cmds-mainporcelain.txt[]
 417
 418 Ancillary Commands
 419 ~~~~~~~~~~~~~~~~~~
 420 Manipulators:
 421
 422 include::cmds-ancillarymanipulators.txt[]
 423
 424 Interrogators:
 425
 426 include::cmds-ancillaryinterrogators.txt[]
 427
 428
 429 Interacting with Others
 430 ~~~~~~~~~~~~~~~~~~~~~~~
 431
 432 These commands are to interact with foreign SCM and with other
 433 people via patch over e-mail.
 434
 435 include::cmds-foreignscminterface.txt[]
 436
 437
 438 Low-level commands (plumbing)
 439 -----------------------------
 440
 441 Although git includes its
 442 own porcelain layer, its low-level commands are sufficient to support
 443 development of alternative porcelains.  Developers of such porcelains
 444 might start by reading about linkgit:git-update-index[1] and
 445 linkgit:git-read-tree[1].
 446
 447 The interface (input, output, set of options and the semantics)
 448 to these low-level commands are meant to be a lot more stable
 449 than Porcelain level commands, because these commands are
 450 primarily for scripted use.  The interface to Porcelain commands
 451 on the other hand are subject to change in order to improve the
 452 end user experience.
 453
 454 The following description divides
 455 the low-level commands into commands that manipulate objects (in
 456 the repository, index, and working tree), commands that interrogate and
 457 compare objects, and commands that move objects and references between
 458 repositories.
 459
 460
 461 Manipulation commands
 462 ~~~~~~~~~~~~~~~~~~~~~
 463
 464 include::cmds-plumbingmanipulators.txt[]
 465
 466
 467 Interrogation commands
 468 ~~~~~~~~~~~~~~~~~~~~~~
 469
 470 include::cmds-plumbinginterrogators.txt[]
 471
 472 In general, the interrogate commands do not touch the files in
 473 the working tree.
 474
 475
 476 Synching repositories
 477 ~~~~~~~~~~~~~~~~~~~~~
 478
 479 include::cmds-synchingrepositories.txt[]
 480
 481 The following are helper commands used by the above; end users
 482 typically do not use them directly.
 483
 484 include::cmds-synchelpers.txt[]
 485
 486
 487 Internal helper commands
 488 ~~~~~~~~~~~~~~~~~~~~~~~~
 489
 490 These are internal helper commands used by other commands; end
 491 users typically do not use them directly.
 492
 493 include::cmds-purehelpers.txt[]
 494
 495
 496 Configuration Mechanism
 497 -----------------------
 498
 499 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 500 is used to hold per-repository configuration options.  It is a
 501 simple text file modeled after `.ini` format familiar to some
 502 people.  Here is an example:
 503
 504 ------------
 505 #
 506 # A '#' or ';' character indicates a comment.
 507 #
 508
 509 ; core variables
 510 [core]
 511         ; Don't trust file modes
 512         filemode = false
 513
 514 ; user identity
 515 [user]
 516         name = "Junio C Hamano"
 517         email = "junkio@twinsun.com"
 518
 519 ------------
 520
 521 Various commands read from the configuration file and adjust
 522 their operation accordingly.  See linkgit:git-config[1] for a
 523 list.
 524
 525
 526 Identifier Terminology
 527 ----------------------
 528 <object>::
 529         Indicates the object name for any type of object.
 530
 531 <blob>::
 532         Indicates a blob object name.
 533
 534 <tree>::
 535         Indicates a tree object name.
 536
 537 <commit>::
 538         Indicates a commit object name.
 539
 540 <tree-ish>::
 541         Indicates a tree, commit or tag object name.  A
 542         command that takes a <tree-ish> argument ultimately wants to
 543         operate on a <tree> object but automatically dereferences
 544         <commit> and <tag> objects that point at a <tree>.
 545
 546 <commit-ish>::
 547         Indicates a commit or tag object name.  A
 548         command that takes a <commit-ish> argument ultimately wants to
 549         operate on a <commit> object but automatically dereferences
 550         <tag> objects that point at a <commit>.
 551
 552 <type>::
 553         Indicates that an object type is required.
 554         Currently one of: `blob`, `tree`, `commit`, or `tag`.
 555
 556 <file>::
 557         Indicates a filename - almost always relative to the
 558         root of the tree structure `GIT_INDEX_FILE` describes.
 559
 560 Symbolic Identifiers
 561 --------------------
 562 Any git command accepting any <object> can also use the following
 563 symbolic notation:
 564
 565 HEAD::
 566         indicates the head of the current branch.
 567
 568 <tag>::
 569         a valid tag 'name'
 570         (i.e. a `refs/tags/<tag>` reference).
 571
 572 <head>::
 573         a valid head 'name'
 574         (i.e. a `refs/heads/<head>` reference).
 575
 576 For a more complete list of ways to spell object names, see
 577 "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
 578
 579
 580 File/Directory Structure
 581 ------------------------
 582
 583 Please see the linkgit:gitrepository-layout[5] document.
 584
 585 Read linkgit:githooks[5] for more details about each hook.
 586
 587 Higher level SCMs may provide and manage additional information in the
 588 `$GIT_DIR`.
 589
 590
 591 Terminology
 592 -----------
 593 Please see linkgit:gitglossary[7].
 594
 595
 596 Environment Variables
 597 ---------------------
 598 Various git commands use the following environment variables:
 599
 600 The git Repository
 601 ~~~~~~~~~~~~~~~~~~
 602 These environment variables apply to 'all' core git commands. Nb: it
 603 is worth noting that they may be used/overridden by SCMS sitting above
 604 git so take care if using Cogito etc.
 605
 606 'GIT_INDEX_FILE'::
 607         This environment allows the specification of an alternate
 608         index file. If not specified, the default of `$GIT_DIR/index`
 609         is used.
 610
 611 'GIT_OBJECT_DIRECTORY'::
 612         If the object storage directory is specified via this
 613         environment variable then the sha1 directories are created
 614         underneath - otherwise the default `$GIT_DIR/objects`
 615         directory is used.
 616
 617 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 618         Due to the immutable nature of git objects, old objects can be
 619         archived into shared, read-only directories. This variable
 620         specifies a ":" separated (on Windows ";" separated) list
 621         of git object directories which can be used to search for git
 622         objects. New objects will not be written to these directories.
 623
 624 'GIT_DIR'::
 625         If the 'GIT_DIR' environment variable is set then it
 626         specifies a path to use instead of the default `.git`
 627         for the base of the repository.
 628
 629 'GIT_WORK_TREE'::
 630         Set the path to the working tree.  The value will not be
 631         used in combination with repositories found automatically in
 632         a .git directory (i.e. $GIT_DIR is not set).
 633         This can also be controlled by the '--work-tree' command line
 634         option and the core.worktree configuration variable.
 635
 636 'GIT_NAMESPACE'::
 637         Set the git namespace; see linkgit:gitnamespaces[7] for details.
 638         The '--namespace' command-line option also sets this value.
 639
 640 'GIT_CEILING_DIRECTORIES'::
 641         This should be a colon-separated list of absolute paths.
 642         If set, it is a list of directories that git should not chdir
 643         up into while looking for a repository directory.
 644         It will not exclude the current working directory or
 645         a GIT_DIR set on the command line or in the environment.
 646         (Useful for excluding slow-loading network directories.)
 647
 648 'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
 649         When run in a directory that does not have ".git" repository
 650         directory, git tries to find such a directory in the parent
 651         directories to find the top of the working tree, but by default it
 652         does not cross filesystem boundaries.  This environment variable
 653         can be set to true to tell git not to stop at filesystem
 654         boundaries.  Like 'GIT_CEILING_DIRECTORIES', this will not affect
 655         an explicit repository directory set via 'GIT_DIR' or on the
 656         command line.
 657
 658 git Commits
 659 ~~~~~~~~~~~
 660 'GIT_AUTHOR_NAME'::
 661 'GIT_AUTHOR_EMAIL'::
 662 'GIT_AUTHOR_DATE'::
 663 'GIT_COMMITTER_NAME'::
 664 'GIT_COMMITTER_EMAIL'::
 665 'GIT_COMMITTER_DATE'::
 666 'EMAIL'::
 667         see linkgit:git-commit-tree[1]
 668
 669 git Diffs
 670 ~~~~~~~~~
 671 'GIT_DIFF_OPTS'::
 672         Only valid setting is "--unified=??" or "-u??" to set the
 673         number of context lines shown when a unified diff is created.
 674         This takes precedence over any "-U" or "--unified" option
 675         value passed on the git diff command line.
 676
 677 'GIT_EXTERNAL_DIFF'::
 678         When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 679         program named by it is called, instead of the diff invocation
 680         described above.  For a path that is added, removed, or modified,
 681         'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 682
 683         path old-file old-hex old-mode new-file new-hex new-mode
 684 +
 685 where:
 686
 687         <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 688                          contents of <old|new>,
 689         <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 690         <old|new>-mode:: are the octal representation of the file modes.
 691 +
 692 The file parameters can point at the user's working file
 693 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 694 when a new file is added), or a temporary file (e.g. `old-file` in the
 695 index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 696 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 697 +
 698 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 699 parameter, <path>.
 700
 701 other
 702 ~~~~~
 703 'GIT_MERGE_VERBOSITY'::
 704         A number controlling the amount of output shown by
 705         the recursive merge strategy.  Overrides merge.verbosity.
 706         See linkgit:git-merge[1]
 707
 708 'GIT_PAGER'::
 709         This environment variable overrides `$PAGER`. If it is set
 710         to an empty string or to the value "cat", git will not launch
 711         a pager.  See also the `core.pager` option in
 712         linkgit:git-config[1].
 713
 714 'GIT_SSH'::
 715         If this environment variable is set then 'git fetch'
 716         and 'git push' will use this command instead
 717         of 'ssh' when they need to connect to a remote system.
 718         The '$GIT_SSH' command will be given exactly two arguments:
 719         the 'username@host' (or just 'host') from the URL and the
 720         shell command to execute on that remote system.
 721 +
 722 To pass options to the program that you want to list in GIT_SSH
 723 you will need to wrap the program and options into a shell script,
 724 then set GIT_SSH to refer to the shell script.
 725 +
 726 Usually it is easier to configure any desired options through your
 727 personal `.ssh/config` file.  Please consult your ssh documentation
 728 for further details.
 729
 730 'GIT_ASKPASS'::
 731         If this environment variable is set, then git commands which need to
 732         acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
 733         will call this program with a suitable prompt as command line argument
 734         and read the password from its STDOUT. See also the 'core.askpass'
 735         option in linkgit:git-config[1].
 736
 737 'GIT_FLUSH'::
 738         If this environment variable is set to "1", then commands such
 739         as 'git blame' (in incremental mode), 'git rev-list', 'git log',
 740         and 'git whatchanged' will force a flush of the output stream
 741         after each commit-oriented record have been flushed.   If this
 742         variable is set to "0", the output of these commands will be done
 743         using completely buffered I/O.   If this environment variable is
 744         not set, git will choose buffered or record-oriented flushing
 745         based on whether stdout appears to be redirected to a file or not.
 746
 747 'GIT_TRACE'::
 748         If this variable is set to "1", "2" or "true" (comparison
 749         is case insensitive), git will print `trace:` messages on
 750         stderr telling about alias expansion, built-in command
 751         execution and external command execution.
 752         If this variable is set to an integer value greater than 1
 753         and lower than 10 (strictly) then git will interpret this
 754         value as an open file descriptor and will try to write the
 755         trace messages into this file descriptor.
 756         Alternatively, if this variable is set to an absolute path
 757         (starting with a '/' character), git will interpret this
 758         as a file path and will try to write the trace messages
 759         into it.
 760
 761 Discussion[[Discussion]]
 762 ------------------------
 763
 764 More detail on the following is available from the
 765 link:user-manual.html#git-concepts[git concepts chapter of the
 766 user-manual] and linkgit:gitcore-tutorial[7].
 767
 768 A git project normally consists of a working directory with a ".git"
 769 subdirectory at the top level.  The .git directory contains, among other
 770 things, a compressed object database representing the complete history
 771 of the project, an "index" file which links that history to the current
 772 contents of the working tree, and named pointers into that history such
 773 as tags and branch heads.
 774
 775 The object database contains objects of three main types: blobs, which
 776 hold file data; trees, which point to blobs and other trees to build up
 777 directory hierarchies; and commits, which each reference a single tree
 778 and some number of parent commits.
 779
 780 The commit, equivalent to what other systems call a "changeset" or
 781 "version", represents a step in the project's history, and each parent
 782 represents an immediately preceding step.  Commits with more than one
 783 parent represent merges of independent lines of development.
 784
 785 All objects are named by the SHA1 hash of their contents, normally
 786 written as a string of 40 hex digits.  Such names are globally unique.
 787 The entire history leading up to a commit can be vouched for by signing
 788 just that commit.  A fourth object type, the tag, is provided for this
 789 purpose.
 790
 791 When first created, objects are stored in individual files, but for
 792 efficiency may later be compressed together into "pack files".
 793
 794 Named pointers called refs mark interesting points in history.  A ref
 795 may contain the SHA1 name of an object or the name of another ref.  Refs
 796 with names beginning `ref/head/` contain the SHA1 name of the most
 797 recent commit (or "head") of a branch under development.  SHA1 names of
 798 tags of interest are stored under `ref/tags/`.  A special ref named
 799 `HEAD` contains the name of the currently checked-out branch.
 800
 801 The index file is initialized with a list of all paths and, for each
 802 path, a blob object and a set of attributes.  The blob object represents
 803 the contents of the file as of the head of the current branch.  The
 804 attributes (last modified time, size, etc.) are taken from the
 805 corresponding file in the working tree.  Subsequent changes to the
 806 working tree can be found by comparing these attributes.  The index may
 807 be updated with new content, and new commits may be created from the
 808 content stored in the index.
 809
 810 The index is also capable of storing multiple entries (called "stages")
 811 for a given pathname.  These stages are used to hold the various
 812 unmerged version of a file when a merge is in progress.
 813
 814 Authors
 815 -------
 816 Git was started by Linus Torvalds, and is currently maintained by Junio
 817 C Hamano. Numerous contributions have come from the git mailing list
 818 <git@vger.kernel.org>. For a more complete list of contributors, see
 819 http://git-scm.com/about. If you have a clone of git.git itself, the
 820 output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
 821 the authors for specific parts of the project.
 822
 823 Reporting Bugs
 824 --------------
 825
 826 Report bugs to the Git mailing list <git@vger.kernel.org> where the
 827 development and maintenance is primarily done.  You do not have to be
 828 subscribed to the list to send a message there.
 829
 830 SEE ALSO
 831 --------
 832 linkgit:gittutorial[7], linkgit:gittutorial-2[7],
 833 link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
 834 linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
 835 linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
 836 linkgit:gitworkflows[7]
 837
 838 GIT
 839 ---
 840 Part of the linkgit:git[1] suite