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
  26 commands.  The link:user-manual.html[Git User's Manual] has a more
  27 in-depth introduction.
  28
  29 After you mastered the basic concepts, you can come back to this
  30 page to learn what commands git offers.  You can learn more about
  31 individual git commands with "git help command".  linkgit:gitcli[7]
  32 manual page gives you an overview of the command line command syntax.
  33
  34 Formatted and hyperlinked version of the latest git documentation
  35 can be viewed at `http://git-htmldocs.googlecode.com/git/git.html`.
  36
  37 ifdef::stalenotes[]
  38 [NOTE]
  39 ============
  40
  41 You are reading the documentation for the latest (possibly
  42 unreleased) version of git, that is available from 'master'
  43 branch of the `git.git` repository.
  44 Documentation for older releases are available here:
  45
  46 * link:v1.7.12/git.html[documentation for release 1.7.12]
  47
  48 * release notes for
  49   link:RelNotes/1.7.12.txt[1.7.12].
  50
  51 * link:v1.7.11.7/git.html[documentation for release 1.7.11.7]
  52
  53 * release notes for
  54   link:RelNotes/1.7.11.7.txt[1.7.11.7],
  55   link:RelNotes/1.7.11.6.txt[1.7.11.6],
  56   link:RelNotes/1.7.11.5.txt[1.7.11.5],
  57   link:RelNotes/1.7.11.4.txt[1.7.11.4],
  58   link:RelNotes/1.7.11.3.txt[1.7.11.3],
  59   link:RelNotes/1.7.11.2.txt[1.7.11.2],
  60   link:RelNotes/1.7.11.1.txt[1.7.11.1],
  61   link:RelNotes/1.7.11.txt[1.7.11].
  62
  63 * link:v1.7.10.5/git.html[documentation for release 1.7.10.5]
  64
  65 * release notes for
  66   link:RelNotes/1.7.10.5.txt[1.7.10.5],
  67   link:RelNotes/1.7.10.4.txt[1.7.10.4],
  68   link:RelNotes/1.7.10.3.txt[1.7.10.3],
  69   link:RelNotes/1.7.10.2.txt[1.7.10.2],
  70   link:RelNotes/1.7.10.1.txt[1.7.10.1],
  71   link:RelNotes/1.7.10.txt[1.7.10].
  72
  73 * link:v1.7.9.7/git.html[documentation for release 1.7.9.7]
  74
  75 * release notes for
  76   link:RelNotes/1.7.9.7.txt[1.7.9.7],
  77   link:RelNotes/1.7.9.6.txt[1.7.9.6],
  78   link:RelNotes/1.7.9.5.txt[1.7.9.5],
  79   link:RelNotes/1.7.9.4.txt[1.7.9.4],
  80   link:RelNotes/1.7.9.3.txt[1.7.9.3],
  81   link:RelNotes/1.7.9.2.txt[1.7.9.2],
  82   link:RelNotes/1.7.9.1.txt[1.7.9.1],
  83   link:RelNotes/1.7.9.txt[1.7.9].
  84
  85 * link:v1.7.8.6/git.html[documentation for release 1.7.8.6]
  86
  87 * release notes for
  88   link:RelNotes/1.7.8.6.txt[1.7.8.6],
  89   link:RelNotes/1.7.8.5.txt[1.7.8.5],
  90   link:RelNotes/1.7.8.4.txt[1.7.8.4],
  91   link:RelNotes/1.7.8.3.txt[1.7.8.3],
  92   link:RelNotes/1.7.8.2.txt[1.7.8.2],
  93   link:RelNotes/1.7.8.1.txt[1.7.8.1],
  94   link:RelNotes/1.7.8.txt[1.7.8].
  95
  96 * link:v1.7.7.7/git.html[documentation for release 1.7.7.7]
  97
  98 * release notes for
  99   link:RelNotes/1.7.7.7.txt[1.7.7.7],
 100   link:RelNotes/1.7.7.6.txt[1.7.7.6],
 101   link:RelNotes/1.7.7.5.txt[1.7.7.5],
 102   link:RelNotes/1.7.7.4.txt[1.7.7.4],
 103   link:RelNotes/1.7.7.3.txt[1.7.7.3],
 104   link:RelNotes/1.7.7.2.txt[1.7.7.2],
 105   link:RelNotes/1.7.7.1.txt[1.7.7.1],
 106   link:RelNotes/1.7.7.txt[1.7.7].
 107
 108 * link:v1.7.6.6/git.html[documentation for release 1.7.6.6]
 109
 110 * release notes for
 111   link:RelNotes/1.7.6.6.txt[1.7.6.6],
 112   link:RelNotes/1.7.6.5.txt[1.7.6.5],
 113   link:RelNotes/1.7.6.4.txt[1.7.6.4],
 114   link:RelNotes/1.7.6.3.txt[1.7.6.3],
 115   link:RelNotes/1.7.6.2.txt[1.7.6.2],
 116   link:RelNotes/1.7.6.1.txt[1.7.6.1],
 117   link:RelNotes/1.7.6.txt[1.7.6].
 118
 119 * link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
 120
 121 * release notes for
 122   link:RelNotes/1.7.5.4.txt[1.7.5.4],
 123   link:RelNotes/1.7.5.3.txt[1.7.5.3],
 124   link:RelNotes/1.7.5.2.txt[1.7.5.2],
 125   link:RelNotes/1.7.5.1.txt[1.7.5.1],
 126   link:RelNotes/1.7.5.txt[1.7.5].
 127
 128 * link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
 129
 130 * release notes for
 131   link:RelNotes/1.7.4.5.txt[1.7.4.5],
 132   link:RelNotes/1.7.4.4.txt[1.7.4.4],
 133   link:RelNotes/1.7.4.3.txt[1.7.4.3],
 134   link:RelNotes/1.7.4.2.txt[1.7.4.2],
 135   link:RelNotes/1.7.4.1.txt[1.7.4.1],
 136   link:RelNotes/1.7.4.txt[1.7.4].
 137
 138 * link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
 139
 140 * release notes for
 141   link:RelNotes/1.7.3.5.txt[1.7.3.5],
 142   link:RelNotes/1.7.3.4.txt[1.7.3.4],
 143   link:RelNotes/1.7.3.3.txt[1.7.3.3],
 144   link:RelNotes/1.7.3.2.txt[1.7.3.2],
 145   link:RelNotes/1.7.3.1.txt[1.7.3.1],
 146   link:RelNotes/1.7.3.txt[1.7.3].
 147
 148 * link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
 149
 150 * release notes for
 151   link:RelNotes/1.7.2.5.txt[1.7.2.5],
 152   link:RelNotes/1.7.2.4.txt[1.7.2.4],
 153   link:RelNotes/1.7.2.3.txt[1.7.2.3],
 154   link:RelNotes/1.7.2.2.txt[1.7.2.2],
 155   link:RelNotes/1.7.2.1.txt[1.7.2.1],
 156   link:RelNotes/1.7.2.txt[1.7.2].
 157
 158 * link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
 159
 160 * release notes for
 161   link:RelNotes/1.7.1.4.txt[1.7.1.4],
 162   link:RelNotes/1.7.1.3.txt[1.7.1.3],
 163   link:RelNotes/1.7.1.2.txt[1.7.1.2],
 164   link:RelNotes/1.7.1.1.txt[1.7.1.1],
 165   link:RelNotes/1.7.1.txt[1.7.1].
 166
 167 * link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
 168
 169 * release notes for
 170   link:RelNotes/1.7.0.9.txt[1.7.0.9],
 171   link:RelNotes/1.7.0.8.txt[1.7.0.8],
 172   link:RelNotes/1.7.0.7.txt[1.7.0.7],
 173   link:RelNotes/1.7.0.6.txt[1.7.0.6],
 174   link:RelNotes/1.7.0.5.txt[1.7.0.5],
 175   link:RelNotes/1.7.0.4.txt[1.7.0.4],
 176   link:RelNotes/1.7.0.3.txt[1.7.0.3],
 177   link:RelNotes/1.7.0.2.txt[1.7.0.2],
 178   link:RelNotes/1.7.0.1.txt[1.7.0.1],
 179   link:RelNotes/1.7.0.txt[1.7.0].
 180
 181 * link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
 182
 183 * release notes for
 184   link:RelNotes/1.6.6.3.txt[1.6.6.3],
 185   link:RelNotes/1.6.6.2.txt[1.6.6.2],
 186   link:RelNotes/1.6.6.1.txt[1.6.6.1],
 187   link:RelNotes/1.6.6.txt[1.6.6].
 188
 189 * link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
 190
 191 * release notes for
 192   link:RelNotes/1.6.5.9.txt[1.6.5.9],
 193   link:RelNotes/1.6.5.8.txt[1.6.5.8],
 194   link:RelNotes/1.6.5.7.txt[1.6.5.7],
 195   link:RelNotes/1.6.5.6.txt[1.6.5.6],
 196   link:RelNotes/1.6.5.5.txt[1.6.5.5],
 197   link:RelNotes/1.6.5.4.txt[1.6.5.4],
 198   link:RelNotes/1.6.5.3.txt[1.6.5.3],
 199   link:RelNotes/1.6.5.2.txt[1.6.5.2],
 200   link:RelNotes/1.6.5.1.txt[1.6.5.1],
 201   link:RelNotes/1.6.5.txt[1.6.5].
 202
 203 * link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
 204
 205 * release notes for
 206   link:RelNotes/1.6.4.5.txt[1.6.4.5],
 207   link:RelNotes/1.6.4.4.txt[1.6.4.4],
 208   link:RelNotes/1.6.4.3.txt[1.6.4.3],
 209   link:RelNotes/1.6.4.2.txt[1.6.4.2],
 210   link:RelNotes/1.6.4.1.txt[1.6.4.1],
 211   link:RelNotes/1.6.4.txt[1.6.4].
 212
 213 * link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
 214
 215 * release notes for
 216   link:RelNotes/1.6.3.4.txt[1.6.3.4],
 217   link:RelNotes/1.6.3.3.txt[1.6.3.3],
 218   link:RelNotes/1.6.3.2.txt[1.6.3.2],
 219   link:RelNotes/1.6.3.1.txt[1.6.3.1],
 220   link:RelNotes/1.6.3.txt[1.6.3].
 221
 222 * release notes for
 223   link:RelNotes/1.6.2.5.txt[1.6.2.5],
 224   link:RelNotes/1.6.2.4.txt[1.6.2.4],
 225   link:RelNotes/1.6.2.3.txt[1.6.2.3],
 226   link:RelNotes/1.6.2.2.txt[1.6.2.2],
 227   link:RelNotes/1.6.2.1.txt[1.6.2.1],
 228   link:RelNotes/1.6.2.txt[1.6.2].
 229
 230 * link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
 231
 232 * release notes for
 233   link:RelNotes/1.6.1.3.txt[1.6.1.3],
 234   link:RelNotes/1.6.1.2.txt[1.6.1.2],
 235   link:RelNotes/1.6.1.1.txt[1.6.1.1],
 236   link:RelNotes/1.6.1.txt[1.6.1].
 237
 238 * link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
 239
 240 * release notes for
 241   link:RelNotes/1.6.0.6.txt[1.6.0.6],
 242   link:RelNotes/1.6.0.5.txt[1.6.0.5],
 243   link:RelNotes/1.6.0.4.txt[1.6.0.4],
 244   link:RelNotes/1.6.0.3.txt[1.6.0.3],
 245   link:RelNotes/1.6.0.2.txt[1.6.0.2],
 246   link:RelNotes/1.6.0.1.txt[1.6.0.1],
 247   link:RelNotes/1.6.0.txt[1.6.0].
 248
 249 * link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
 250
 251 * release notes for
 252   link:RelNotes/1.5.6.6.txt[1.5.6.6],
 253   link:RelNotes/1.5.6.5.txt[1.5.6.5],
 254   link:RelNotes/1.5.6.4.txt[1.5.6.4],
 255   link:RelNotes/1.5.6.3.txt[1.5.6.3],
 256   link:RelNotes/1.5.6.2.txt[1.5.6.2],
 257   link:RelNotes/1.5.6.1.txt[1.5.6.1],
 258   link:RelNotes/1.5.6.txt[1.5.6].
 259
 260 * link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
 261
 262 * release notes for
 263   link:RelNotes/1.5.5.6.txt[1.5.5.6],
 264   link:RelNotes/1.5.5.5.txt[1.5.5.5],
 265   link:RelNotes/1.5.5.4.txt[1.5.5.4],
 266   link:RelNotes/1.5.5.3.txt[1.5.5.3],
 267   link:RelNotes/1.5.5.2.txt[1.5.5.2],
 268   link:RelNotes/1.5.5.1.txt[1.5.5.1],
 269   link:RelNotes/1.5.5.txt[1.5.5].
 270
 271 * link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
 272
 273 * release notes for
 274   link:RelNotes/1.5.4.7.txt[1.5.4.7],
 275   link:RelNotes/1.5.4.6.txt[1.5.4.6],
 276   link:RelNotes/1.5.4.5.txt[1.5.4.5],
 277   link:RelNotes/1.5.4.4.txt[1.5.4.4],
 278   link:RelNotes/1.5.4.3.txt[1.5.4.3],
 279   link:RelNotes/1.5.4.2.txt[1.5.4.2],
 280   link:RelNotes/1.5.4.1.txt[1.5.4.1],
 281   link:RelNotes/1.5.4.txt[1.5.4].
 282
 283 * link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
 284
 285 * release notes for
 286   link:RelNotes/1.5.3.8.txt[1.5.3.8],
 287   link:RelNotes/1.5.3.7.txt[1.5.3.7],
 288   link:RelNotes/1.5.3.6.txt[1.5.3.6],
 289   link:RelNotes/1.5.3.5.txt[1.5.3.5],
 290   link:RelNotes/1.5.3.4.txt[1.5.3.4],
 291   link:RelNotes/1.5.3.3.txt[1.5.3.3],
 292   link:RelNotes/1.5.3.2.txt[1.5.3.2],
 293   link:RelNotes/1.5.3.1.txt[1.5.3.1],
 294   link:RelNotes/1.5.3.txt[1.5.3].
 295
 296 * link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
 297
 298 * release notes for
 299   link:RelNotes/1.5.2.5.txt[1.5.2.5],
 300   link:RelNotes/1.5.2.4.txt[1.5.2.4],
 301   link:RelNotes/1.5.2.3.txt[1.5.2.3],
 302   link:RelNotes/1.5.2.2.txt[1.5.2.2],
 303   link:RelNotes/1.5.2.1.txt[1.5.2.1],
 304   link:RelNotes/1.5.2.txt[1.5.2].
 305
 306 * link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
 307
 308 * release notes for
 309   link:RelNotes/1.5.1.6.txt[1.5.1.6],
 310   link:RelNotes/1.5.1.5.txt[1.5.1.5],
 311   link:RelNotes/1.5.1.4.txt[1.5.1.4],
 312   link:RelNotes/1.5.1.3.txt[1.5.1.3],
 313   link:RelNotes/1.5.1.2.txt[1.5.1.2],
 314   link:RelNotes/1.5.1.1.txt[1.5.1.1],
 315   link:RelNotes/1.5.1.txt[1.5.1].
 316
 317 * link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
 318
 319 * release notes for
 320   link:RelNotes/1.5.0.7.txt[1.5.0.7],
 321   link:RelNotes/1.5.0.6.txt[1.5.0.6],
 322   link:RelNotes/1.5.0.5.txt[1.5.0.5],
 323   link:RelNotes/1.5.0.3.txt[1.5.0.3],
 324   link:RelNotes/1.5.0.2.txt[1.5.0.2],
 325   link:RelNotes/1.5.0.1.txt[1.5.0.1],
 326   link:RelNotes/1.5.0.txt[1.5.0].
 327
 328 * documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 329   link:v1.3.3/git.html[1.3.3],
 330   link:v1.2.6/git.html[1.2.6],
 331   link:v1.0.13/git.html[1.0.13].
 332
 333 ============
 334
 335 endif::stalenotes[]
 336
 337 OPTIONS
 338 -------
 339 --version::
 340         Prints the git suite version that the 'git' program came from.
 341
 342 --help::
 343         Prints the synopsis and a list of the most commonly used
 344         commands. If the option '--all' or '-a' is given then all
 345         available commands are printed. If a git command is named this
 346         option will bring up the manual page for that command.
 347 +
 348 Other options are available to control how the manual page is
 349 displayed. See linkgit:git-help[1] for more information,
 350 because `git --help ...` is converted internally into `git
 351 help ...`.
 352
 353 -c <name>=<value>::
 354         Pass a configuration parameter to the command. The value
 355         given will override values from configuration files.
 356         The <name> is expected in the same format as listed by
 357         'git config' (subkeys separated by dots).
 358
 359 --exec-path[=<path>]::
 360         Path to wherever your core git programs are installed.
 361         This can also be controlled by setting the GIT_EXEC_PATH
 362         environment variable. If no path is given, 'git' will print
 363         the current setting and then exit.
 364
 365 --html-path::
 366         Print the path, without trailing slash, where git's HTML
 367         documentation is installed and exit.
 368
 369 --man-path::
 370         Print the manpath (see `man(1)`) for the man pages for
 371         this version of git and exit.
 372
 373 --info-path::
 374         Print the path where the Info files documenting this
 375         version of git are installed and exit.
 376
 377 -p::
 378 --paginate::
 379         Pipe all output into 'less' (or if set, $PAGER) if standard
 380         output is a terminal.  This overrides the `pager.<cmd>`
 381         configuration options (see the "Configuration Mechanism" section
 382         below).
 383
 384 --no-pager::
 385         Do not pipe git output into a pager.
 386
 387 --git-dir=<path>::
 388         Set the path to the repository. This can also be controlled by
 389         setting the GIT_DIR environment variable. It can be an absolute
 390         path or relative path to current working directory.
 391
 392 --work-tree=<path>::
 393         Set the path to the working tree. It can be an absolute path
 394         or a path relative to the current working directory.
 395         This can also be controlled by setting the GIT_WORK_TREE
 396         environment variable and the core.worktree configuration
 397         variable (see core.worktree in linkgit:git-config[1] for a
 398         more detailed discussion).
 399
 400 --namespace=<path>::
 401         Set the git namespace.  See linkgit:gitnamespaces[7] for more
 402         details.  Equivalent to setting the `GIT_NAMESPACE` environment
 403         variable.
 404
 405 --bare::
 406         Treat the repository as a bare repository.  If GIT_DIR
 407         environment is not set, it is set to the current working
 408         directory.
 409
 410 --no-replace-objects::
 411         Do not use replacement refs to replace git objects. See
 412         linkgit:git-replace[1] for more information.
 413
 414
 415 GIT COMMANDS
 416 ------------
 417
 418 We divide git into high level ("porcelain") commands and low level
 419 ("plumbing") commands.
 420
 421 High-level commands (porcelain)
 422 -------------------------------
 423
 424 We separate the porcelain commands into the main commands and some
 425 ancillary user utilities.
 426
 427 Main porcelain commands
 428 ~~~~~~~~~~~~~~~~~~~~~~~
 429
 430 include::cmds-mainporcelain.txt[]
 431
 432 Ancillary Commands
 433 ~~~~~~~~~~~~~~~~~~
 434 Manipulators:
 435
 436 include::cmds-ancillarymanipulators.txt[]
 437
 438 Interrogators:
 439
 440 include::cmds-ancillaryinterrogators.txt[]
 441
 442
 443 Interacting with Others
 444 ~~~~~~~~~~~~~~~~~~~~~~~
 445
 446 These commands are to interact with foreign SCM and with other
 447 people via patch over e-mail.
 448
 449 include::cmds-foreignscminterface.txt[]
 450
 451
 452 Low-level commands (plumbing)
 453 -----------------------------
 454
 455 Although git includes its
 456 own porcelain layer, its low-level commands are sufficient to support
 457 development of alternative porcelains.  Developers of such porcelains
 458 might start by reading about linkgit:git-update-index[1] and
 459 linkgit:git-read-tree[1].
 460
 461 The interface (input, output, set of options and the semantics)
 462 to these low-level commands are meant to be a lot more stable
 463 than Porcelain level commands, because these commands are
 464 primarily for scripted use.  The interface to Porcelain commands
 465 on the other hand are subject to change in order to improve the
 466 end user experience.
 467
 468 The following description divides
 469 the low-level commands into commands that manipulate objects (in
 470 the repository, index, and working tree), commands that interrogate and
 471 compare objects, and commands that move objects and references between
 472 repositories.
 473
 474
 475 Manipulation commands
 476 ~~~~~~~~~~~~~~~~~~~~~
 477
 478 include::cmds-plumbingmanipulators.txt[]
 479
 480
 481 Interrogation commands
 482 ~~~~~~~~~~~~~~~~~~~~~~
 483
 484 include::cmds-plumbinginterrogators.txt[]
 485
 486 In general, the interrogate commands do not touch the files in
 487 the working tree.
 488
 489
 490 Synching repositories
 491 ~~~~~~~~~~~~~~~~~~~~~
 492
 493 include::cmds-synchingrepositories.txt[]
 494
 495 The following are helper commands used by the above; end users
 496 typically do not use them directly.
 497
 498 include::cmds-synchelpers.txt[]
 499
 500
 501 Internal helper commands
 502 ~~~~~~~~~~~~~~~~~~~~~~~~
 503
 504 These are internal helper commands used by other commands; end
 505 users typically do not use them directly.
 506
 507 include::cmds-purehelpers.txt[]
 508
 509
 510 Configuration Mechanism
 511 -----------------------
 512
 513 Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 514 is used to hold per-repository configuration options.  It is a
 515 simple text file modeled after `.ini` format familiar to some
 516 people.  Here is an example:
 517
 518 ------------
 519 #
 520 # A '#' or ';' character indicates a comment.
 521 #
 522
 523 ; core variables
 524 [core]
 525         ; Don't trust file modes
 526         filemode = false
 527
 528 ; user identity
 529 [user]
 530         name = "Junio C Hamano"
 531         email = "junkio@twinsun.com"
 532
 533 ------------
 534
 535 Various commands read from the configuration file and adjust
 536 their operation accordingly.  See linkgit:git-config[1] for a
 537 list.
 538
 539
 540 Identifier Terminology
 541 ----------------------
 542 <object>::
 543         Indicates the object name for any type of object.
 544
 545 <blob>::
 546         Indicates a blob object name.
 547
 548 <tree>::
 549         Indicates a tree object name.
 550
 551 <commit>::
 552         Indicates a commit object name.
 553
 554 <tree-ish>::
 555         Indicates a tree, commit or tag object name.  A
 556         command that takes a <tree-ish> argument ultimately wants to
 557         operate on a <tree> object but automatically dereferences
 558         <commit> and <tag> objects that point at a <tree>.
 559
 560 <commit-ish>::
 561         Indicates a commit or tag object name.  A
 562         command that takes a <commit-ish> argument ultimately wants to
 563         operate on a <commit> object but automatically dereferences
 564         <tag> objects that point at a <commit>.
 565
 566 <type>::
 567         Indicates that an object type is required.
 568         Currently one of: `blob`, `tree`, `commit`, or `tag`.
 569
 570 <file>::
 571         Indicates a filename - almost always relative to the
 572         root of the tree structure `GIT_INDEX_FILE` describes.
 573
 574 Symbolic Identifiers
 575 --------------------
 576 Any git command accepting any <object> can also use the following
 577 symbolic notation:
 578
 579 HEAD::
 580         indicates the head of the current branch.
 581
 582 <tag>::
 583         a valid tag 'name'
 584         (i.e. a `refs/tags/<tag>` reference).
 585
 586 <head>::
 587         a valid head 'name'
 588         (i.e. a `refs/heads/<head>` reference).
 589
 590 For a more complete list of ways to spell object names, see
 591 "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
 592
 593
 594 File/Directory Structure
 595 ------------------------
 596
 597 Please see the linkgit:gitrepository-layout[5] document.
 598
 599 Read linkgit:githooks[5] for more details about each hook.
 600
 601 Higher level SCMs may provide and manage additional information in the
 602 `$GIT_DIR`.
 603
 604
 605 Terminology
 606 -----------
 607 Please see linkgit:gitglossary[7].
 608
 609
 610 Environment Variables
 611 ---------------------
 612 Various git commands use the following environment variables:
 613
 614 The git Repository
 615 ~~~~~~~~~~~~~~~~~~
 616 These environment variables apply to 'all' core git commands. Nb: it
 617 is worth noting that they may be used/overridden by SCMS sitting above
 618 git so take care if using Cogito etc.
 619
 620 'GIT_INDEX_FILE'::
 621         This environment allows the specification of an alternate
 622         index file. If not specified, the default of `$GIT_DIR/index`
 623         is used.
 624
 625 'GIT_OBJECT_DIRECTORY'::
 626         If the object storage directory is specified via this
 627         environment variable then the sha1 directories are created
 628         underneath - otherwise the default `$GIT_DIR/objects`
 629         directory is used.
 630
 631 'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 632         Due to the immutable nature of git objects, old objects can be
 633         archived into shared, read-only directories. This variable
 634         specifies a ":" separated (on Windows ";" separated) list
 635         of git object directories which can be used to search for git
 636         objects. New objects will not be written to these directories.
 637
 638 'GIT_DIR'::
 639         If the 'GIT_DIR' environment variable is set then it
 640         specifies a path to use instead of the default `.git`
 641         for the base of the repository.
 642
 643 'GIT_WORK_TREE'::
 644         Set the path to the working tree.  The value will not be
 645         used in combination with repositories found automatically in
 646         a .git directory (i.e. $GIT_DIR is not set).
 647         This can also be controlled by the '--work-tree' command line
 648         option and the core.worktree configuration variable.
 649
 650 'GIT_NAMESPACE'::
 651         Set the git namespace; see linkgit:gitnamespaces[7] for details.
 652         The '--namespace' command-line option also sets this value.
 653
 654 'GIT_CEILING_DIRECTORIES'::
 655         This should be a colon-separated list of absolute paths.
 656         If set, it is a list of directories that git should not chdir
 657         up into while looking for a repository directory.
 658         It will not exclude the current working directory or
 659         a GIT_DIR set on the command line or in the environment.
 660         (Useful for excluding slow-loading network directories.)
 661
 662 'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
 663         When run in a directory that does not have ".git" repository
 664         directory, git tries to find such a directory in the parent
 665         directories to find the top of the working tree, but by default it
 666         does not cross filesystem boundaries.  This environment variable
 667         can be set to true to tell git not to stop at filesystem
 668         boundaries.  Like 'GIT_CEILING_DIRECTORIES', this will not affect
 669         an explicit repository directory set via 'GIT_DIR' or on the
 670         command line.
 671
 672 git Commits
 673 ~~~~~~~~~~~
 674 'GIT_AUTHOR_NAME'::
 675 'GIT_AUTHOR_EMAIL'::
 676 'GIT_AUTHOR_DATE'::
 677 'GIT_COMMITTER_NAME'::
 678 'GIT_COMMITTER_EMAIL'::
 679 'GIT_COMMITTER_DATE'::
 680 'EMAIL'::
 681         see linkgit:git-commit-tree[1]
 682
 683 git Diffs
 684 ~~~~~~~~~
 685 'GIT_DIFF_OPTS'::
 686         Only valid setting is "--unified=??" or "-u??" to set the
 687         number of context lines shown when a unified diff is created.
 688         This takes precedence over any "-U" or "--unified" option
 689         value passed on the git diff command line.
 690
 691 'GIT_EXTERNAL_DIFF'::
 692         When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 693         program named by it is called, instead of the diff invocation
 694         described above.  For a path that is added, removed, or modified,
 695         'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 696
 697         path old-file old-hex old-mode new-file new-hex new-mode
 698 +
 699 where:
 700
 701         <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 702                          contents of <old|new>,
 703         <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 704         <old|new>-mode:: are the octal representation of the file modes.
 705 +
 706 The file parameters can point at the user's working file
 707 (e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 708 when a new file is added), or a temporary file (e.g. `old-file` in the
 709 index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 710 temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 711 +
 712 For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 713 parameter, <path>.
 714
 715 other
 716 ~~~~~
 717 'GIT_MERGE_VERBOSITY'::
 718         A number controlling the amount of output shown by
 719         the recursive merge strategy.  Overrides merge.verbosity.
 720         See linkgit:git-merge[1]
 721
 722 'GIT_PAGER'::
 723         This environment variable overrides `$PAGER`. If it is set
 724         to an empty string or to the value "cat", git will not launch
 725         a pager.  See also the `core.pager` option in
 726         linkgit:git-config[1].
 727
 728 'GIT_EDITOR'::
 729         This environment variable overrides `$EDITOR` and `$VISUAL`.
 730         It is used by several git commands when, on interactive mode,
 731         an editor is to be launched. See also linkgit:git-var[1]
 732         and the `core.editor` option in linkgit:git-config[1].
 733
 734 'GIT_SSH'::
 735         If this environment variable is set then 'git fetch'
 736         and 'git push' will use this command instead
 737         of 'ssh' when they need to connect to a remote system.
 738         The '$GIT_SSH' command will be given exactly two arguments:
 739         the 'username@host' (or just 'host') from the URL and the
 740         shell command to execute on that remote system.
 741 +
 742 To pass options to the program that you want to list in GIT_SSH
 743 you will need to wrap the program and options into a shell script,
 744 then set GIT_SSH to refer to the shell script.
 745 +
 746 Usually it is easier to configure any desired options through your
 747 personal `.ssh/config` file.  Please consult your ssh documentation
 748 for further details.
 749
 750 'GIT_ASKPASS'::
 751         If this environment variable is set, then git commands which need to
 752         acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
 753         will call this program with a suitable prompt as command line argument
 754         and read the password from its STDOUT. See also the 'core.askpass'
 755         option in linkgit:git-config[1].
 756
 757 'GIT_FLUSH'::
 758         If this environment variable is set to "1", then commands such
 759         as 'git blame' (in incremental mode), 'git rev-list', 'git log',
 760         and 'git whatchanged' will force a flush of the output stream
 761         after each commit-oriented record have been flushed.   If this
 762         variable is set to "0", the output of these commands will be done
 763         using completely buffered I/O.   If this environment variable is
 764         not set, git will choose buffered or record-oriented flushing
 765         based on whether stdout appears to be redirected to a file or not.
 766
 767 'GIT_TRACE'::
 768         If this variable is set to "1", "2" or "true" (comparison
 769         is case insensitive), git will print `trace:` messages on
 770         stderr telling about alias expansion, built-in command
 771         execution and external command execution.
 772         If this variable is set to an integer value greater than 1
 773         and lower than 10 (strictly) then git will interpret this
 774         value as an open file descriptor and will try to write the
 775         trace messages into this file descriptor.
 776         Alternatively, if this variable is set to an absolute path
 777         (starting with a '/' character), git will interpret this
 778         as a file path and will try to write the trace messages
 779         into it.
 780
 781 Discussion[[Discussion]]
 782 ------------------------
 783
 784 More detail on the following is available from the
 785 link:user-manual.html#git-concepts[git concepts chapter of the
 786 user-manual] and linkgit:gitcore-tutorial[7].
 787
 788 A git project normally consists of a working directory with a ".git"
 789 subdirectory at the top level.  The .git directory contains, among other
 790 things, a compressed object database representing the complete history
 791 of the project, an "index" file which links that history to the current
 792 contents of the working tree, and named pointers into that history such
 793 as tags and branch heads.
 794
 795 The object database contains objects of three main types: blobs, which
 796 hold file data; trees, which point to blobs and other trees to build up
 797 directory hierarchies; and commits, which each reference a single tree
 798 and some number of parent commits.
 799
 800 The commit, equivalent to what other systems call a "changeset" or
 801 "version", represents a step in the project's history, and each parent
 802 represents an immediately preceding step.  Commits with more than one
 803 parent represent merges of independent lines of development.
 804
 805 All objects are named by the SHA1 hash of their contents, normally
 806 written as a string of 40 hex digits.  Such names are globally unique.
 807 The entire history leading up to a commit can be vouched for by signing
 808 just that commit.  A fourth object type, the tag, is provided for this
 809 purpose.
 810
 811 When first created, objects are stored in individual files, but for
 812 efficiency may later be compressed together into "pack files".
 813
 814 Named pointers called refs mark interesting points in history.  A ref
 815 may contain the SHA1 name of an object or the name of another ref.  Refs
 816 with names beginning `ref/head/` contain the SHA1 name of the most
 817 recent commit (or "head") of a branch under development.  SHA1 names of
 818 tags of interest are stored under `ref/tags/`.  A special ref named
 819 `HEAD` contains the name of the currently checked-out branch.
 820
 821 The index file is initialized with a list of all paths and, for each
 822 path, a blob object and a set of attributes.  The blob object represents
 823 the contents of the file as of the head of the current branch.  The
 824 attributes (last modified time, size, etc.) are taken from the
 825 corresponding file in the working tree.  Subsequent changes to the
 826 working tree can be found by comparing these attributes.  The index may
 827 be updated with new content, and new commits may be created from the
 828 content stored in the index.
 829
 830 The index is also capable of storing multiple entries (called "stages")
 831 for a given pathname.  These stages are used to hold the various
 832 unmerged version of a file when a merge is in progress.
 833
 834 FURTHER DOCUMENTATION
 835 ---------------------
 836
 837 See the references in the "description" section to get started
 838 using git.  The following is probably more detail than necessary
 839 for a first-time user.
 840
 841 The link:user-manual.html#git-concepts[git concepts chapter of the
 842 user-manual] and linkgit:gitcore-tutorial[7] both provide
 843 introductions to the underlying git architecture.
 844
 845 See linkgit:gitworkflows[7] for an overview of recommended workflows.
 846
 847 See also the link:howto-index.html[howto] documents for some useful
 848 examples.
 849
 850 The internals are documented in the
 851 link:technical/api-index.html[GIT API documentation].
 852
 853 Users migrating from CVS may also want to
 854 read linkgit:gitcvs-migration[7].
 855
 856
 857 Authors
 858 -------
 859 Git was started by Linus Torvalds, and is currently maintained by Junio
 860 C Hamano. Numerous contributions have come from the git mailing list
 861 <git@vger.kernel.org>. For a more complete list of contributors, see
 862 http://git-scm.com/about. If you have a clone of git.git itself, the
 863 output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
 864 the authors for specific parts of the project.
 865
 866 Reporting Bugs
 867 --------------
 868
 869 Report bugs to the Git mailing list <git@vger.kernel.org> where the
 870 development and maintenance is primarily done.  You do not have to be
 871 subscribed to the list to send a message there.
 872
 873 SEE ALSO
 874 --------
 875 linkgit:gittutorial[7], linkgit:gittutorial-2[7],
 876 link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
 877 linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
 878 linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
 879 linkgit:gitworkflows[7]
 880
 881 GIT
 882 ---
 883 Part of the linkgit:git[1] suite