Documentation / git.txton commit Update draft release notes to 1.7.10 (42e52e3)
   1git(1)
   2======
   3
   4NAME
   5----
   6git - the stupid content tracker
   7
   8
   9SYNOPSIS
  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
  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:v1.7.9.3/git.html[documentation for release 1.7.9.3]
  48
  49* release notes for
  50  link:RelNotes/1.7.9.3.txt[1.7.9.3],
  51  link:RelNotes/1.7.9.2.txt[1.7.9.2],
  52  link:RelNotes/1.7.9.1.txt[1.7.9.1],
  53  link:RelNotes/1.7.9.txt[1.7.9].
  54
  55* link:v1.7.8.4/git.html[documentation for release 1.7.8.4]
  56
  57* release notes for
  58  link:RelNotes/1.7.8.4.txt[1.7.8.4],
  59  link:RelNotes/1.7.8.3.txt[1.7.8.3],
  60  link:RelNotes/1.7.8.2.txt[1.7.8.2],
  61  link:RelNotes/1.7.8.1.txt[1.7.8.1],
  62  link:RelNotes/1.7.8.txt[1.7.8].
  63
  64* link:v1.7.7.6/git.html[documentation for release 1.7.7.6]
  65
  66* release notes for
  67  link:RelNotes/1.7.7.6.txt[1.7.7.6],
  68  link:RelNotes/1.7.7.5.txt[1.7.7.5],
  69  link:RelNotes/1.7.7.4.txt[1.7.7.4],
  70  link:RelNotes/1.7.7.3.txt[1.7.7.3],
  71  link:RelNotes/1.7.7.2.txt[1.7.7.2],
  72  link:RelNotes/1.7.7.1.txt[1.7.7.1],
  73  link:RelNotes/1.7.7.txt[1.7.7].
  74
  75* link:v1.7.6.6/git.html[documentation for release 1.7.6.6]
  76
  77* release notes for
  78  link:RelNotes/1.7.6.6.txt[1.7.6.6],
  79  link:RelNotes/1.7.6.5.txt[1.7.6.5],
  80  link:RelNotes/1.7.6.4.txt[1.7.6.4],
  81  link:RelNotes/1.7.6.3.txt[1.7.6.3],
  82  link:RelNotes/1.7.6.2.txt[1.7.6.2],
  83  link:RelNotes/1.7.6.1.txt[1.7.6.1],
  84  link:RelNotes/1.7.6.txt[1.7.6].
  85
  86* link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
  87
  88* release notes for
  89  link:RelNotes/1.7.5.4.txt[1.7.5.4],
  90  link:RelNotes/1.7.5.3.txt[1.7.5.3],
  91  link:RelNotes/1.7.5.2.txt[1.7.5.2],
  92  link:RelNotes/1.7.5.1.txt[1.7.5.1],
  93  link:RelNotes/1.7.5.txt[1.7.5].
  94
  95* link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
  96
  97* release notes for
  98  link:RelNotes/1.7.4.5.txt[1.7.4.5],
  99  link:RelNotes/1.7.4.4.txt[1.7.4.4],
 100  link:RelNotes/1.7.4.3.txt[1.7.4.3],
 101  link:RelNotes/1.7.4.2.txt[1.7.4.2],
 102  link:RelNotes/1.7.4.1.txt[1.7.4.1],
 103  link:RelNotes/1.7.4.txt[1.7.4].
 104
 105* link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
 106
 107* release notes for
 108  link:RelNotes/1.7.3.5.txt[1.7.3.5],
 109  link:RelNotes/1.7.3.4.txt[1.7.3.4],
 110  link:RelNotes/1.7.3.3.txt[1.7.3.3],
 111  link:RelNotes/1.7.3.2.txt[1.7.3.2],
 112  link:RelNotes/1.7.3.1.txt[1.7.3.1],
 113  link:RelNotes/1.7.3.txt[1.7.3].
 114
 115* link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
 116
 117* release notes for
 118  link:RelNotes/1.7.2.5.txt[1.7.2.5],
 119  link:RelNotes/1.7.2.4.txt[1.7.2.4],
 120  link:RelNotes/1.7.2.3.txt[1.7.2.3],
 121  link:RelNotes/1.7.2.2.txt[1.7.2.2],
 122  link:RelNotes/1.7.2.1.txt[1.7.2.1],
 123  link:RelNotes/1.7.2.txt[1.7.2].
 124
 125* link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
 126
 127* release notes for
 128  link:RelNotes/1.7.1.4.txt[1.7.1.4],
 129  link:RelNotes/1.7.1.3.txt[1.7.1.3],
 130  link:RelNotes/1.7.1.2.txt[1.7.1.2],
 131  link:RelNotes/1.7.1.1.txt[1.7.1.1],
 132  link:RelNotes/1.7.1.txt[1.7.1].
 133
 134* link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
 135
 136* release notes for
 137  link:RelNotes/1.7.0.9.txt[1.7.0.9],
 138  link:RelNotes/1.7.0.8.txt[1.7.0.8],
 139  link:RelNotes/1.7.0.7.txt[1.7.0.7],
 140  link:RelNotes/1.7.0.6.txt[1.7.0.6],
 141  link:RelNotes/1.7.0.5.txt[1.7.0.5],
 142  link:RelNotes/1.7.0.4.txt[1.7.0.4],
 143  link:RelNotes/1.7.0.3.txt[1.7.0.3],
 144  link:RelNotes/1.7.0.2.txt[1.7.0.2],
 145  link:RelNotes/1.7.0.1.txt[1.7.0.1],
 146  link:RelNotes/1.7.0.txt[1.7.0].
 147
 148* link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
 149
 150* release notes for
 151  link:RelNotes/1.6.6.3.txt[1.6.6.3],
 152  link:RelNotes/1.6.6.2.txt[1.6.6.2],
 153  link:RelNotes/1.6.6.1.txt[1.6.6.1],
 154  link:RelNotes/1.6.6.txt[1.6.6].
 155
 156* link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
 157
 158* release notes for
 159  link:RelNotes/1.6.5.9.txt[1.6.5.9],
 160  link:RelNotes/1.6.5.8.txt[1.6.5.8],
 161  link:RelNotes/1.6.5.7.txt[1.6.5.7],
 162  link:RelNotes/1.6.5.6.txt[1.6.5.6],
 163  link:RelNotes/1.6.5.5.txt[1.6.5.5],
 164  link:RelNotes/1.6.5.4.txt[1.6.5.4],
 165  link:RelNotes/1.6.5.3.txt[1.6.5.3],
 166  link:RelNotes/1.6.5.2.txt[1.6.5.2],
 167  link:RelNotes/1.6.5.1.txt[1.6.5.1],
 168  link:RelNotes/1.6.5.txt[1.6.5].
 169
 170* link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
 171
 172* release notes for
 173  link:RelNotes/1.6.4.5.txt[1.6.4.5],
 174  link:RelNotes/1.6.4.4.txt[1.6.4.4],
 175  link:RelNotes/1.6.4.3.txt[1.6.4.3],
 176  link:RelNotes/1.6.4.2.txt[1.6.4.2],
 177  link:RelNotes/1.6.4.1.txt[1.6.4.1],
 178  link:RelNotes/1.6.4.txt[1.6.4].
 179
 180* link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
 181
 182* release notes for
 183  link:RelNotes/1.6.3.4.txt[1.6.3.4],
 184  link:RelNotes/1.6.3.3.txt[1.6.3.3],
 185  link:RelNotes/1.6.3.2.txt[1.6.3.2],
 186  link:RelNotes/1.6.3.1.txt[1.6.3.1],
 187  link:RelNotes/1.6.3.txt[1.6.3].
 188
 189* release notes for
 190  link:RelNotes/1.6.2.5.txt[1.6.2.5],
 191  link:RelNotes/1.6.2.4.txt[1.6.2.4],
 192  link:RelNotes/1.6.2.3.txt[1.6.2.3],
 193  link:RelNotes/1.6.2.2.txt[1.6.2.2],
 194  link:RelNotes/1.6.2.1.txt[1.6.2.1],
 195  link:RelNotes/1.6.2.txt[1.6.2].
 196
 197* link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
 198
 199* release notes for
 200  link:RelNotes/1.6.1.3.txt[1.6.1.3],
 201  link:RelNotes/1.6.1.2.txt[1.6.1.2],
 202  link:RelNotes/1.6.1.1.txt[1.6.1.1],
 203  link:RelNotes/1.6.1.txt[1.6.1].
 204
 205* link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
 206
 207* release notes for
 208  link:RelNotes/1.6.0.6.txt[1.6.0.6],
 209  link:RelNotes/1.6.0.5.txt[1.6.0.5],
 210  link:RelNotes/1.6.0.4.txt[1.6.0.4],
 211  link:RelNotes/1.6.0.3.txt[1.6.0.3],
 212  link:RelNotes/1.6.0.2.txt[1.6.0.2],
 213  link:RelNotes/1.6.0.1.txt[1.6.0.1],
 214  link:RelNotes/1.6.0.txt[1.6.0].
 215
 216* link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
 217
 218* release notes for
 219  link:RelNotes/1.5.6.6.txt[1.5.6.6],
 220  link:RelNotes/1.5.6.5.txt[1.5.6.5],
 221  link:RelNotes/1.5.6.4.txt[1.5.6.4],
 222  link:RelNotes/1.5.6.3.txt[1.5.6.3],
 223  link:RelNotes/1.5.6.2.txt[1.5.6.2],
 224  link:RelNotes/1.5.6.1.txt[1.5.6.1],
 225  link:RelNotes/1.5.6.txt[1.5.6].
 226
 227* link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
 228
 229* release notes for
 230  link:RelNotes/1.5.5.6.txt[1.5.5.6],
 231  link:RelNotes/1.5.5.5.txt[1.5.5.5],
 232  link:RelNotes/1.5.5.4.txt[1.5.5.4],
 233  link:RelNotes/1.5.5.3.txt[1.5.5.3],
 234  link:RelNotes/1.5.5.2.txt[1.5.5.2],
 235  link:RelNotes/1.5.5.1.txt[1.5.5.1],
 236  link:RelNotes/1.5.5.txt[1.5.5].
 237
 238* link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
 239
 240* release notes for
 241  link:RelNotes/1.5.4.7.txt[1.5.4.7],
 242  link:RelNotes/1.5.4.6.txt[1.5.4.6],
 243  link:RelNotes/1.5.4.5.txt[1.5.4.5],
 244  link:RelNotes/1.5.4.4.txt[1.5.4.4],
 245  link:RelNotes/1.5.4.3.txt[1.5.4.3],
 246  link:RelNotes/1.5.4.2.txt[1.5.4.2],
 247  link:RelNotes/1.5.4.1.txt[1.5.4.1],
 248  link:RelNotes/1.5.4.txt[1.5.4].
 249
 250* link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
 251
 252* release notes for
 253  link:RelNotes/1.5.3.8.txt[1.5.3.8],
 254  link:RelNotes/1.5.3.7.txt[1.5.3.7],
 255  link:RelNotes/1.5.3.6.txt[1.5.3.6],
 256  link:RelNotes/1.5.3.5.txt[1.5.3.5],
 257  link:RelNotes/1.5.3.4.txt[1.5.3.4],
 258  link:RelNotes/1.5.3.3.txt[1.5.3.3],
 259  link:RelNotes/1.5.3.2.txt[1.5.3.2],
 260  link:RelNotes/1.5.3.1.txt[1.5.3.1],
 261  link:RelNotes/1.5.3.txt[1.5.3].
 262
 263* link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
 264
 265* release notes for
 266  link:RelNotes/1.5.2.5.txt[1.5.2.5],
 267  link:RelNotes/1.5.2.4.txt[1.5.2.4],
 268  link:RelNotes/1.5.2.3.txt[1.5.2.3],
 269  link:RelNotes/1.5.2.2.txt[1.5.2.2],
 270  link:RelNotes/1.5.2.1.txt[1.5.2.1],
 271  link:RelNotes/1.5.2.txt[1.5.2].
 272
 273* link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
 274
 275* release notes for
 276  link:RelNotes/1.5.1.6.txt[1.5.1.6],
 277  link:RelNotes/1.5.1.5.txt[1.5.1.5],
 278  link:RelNotes/1.5.1.4.txt[1.5.1.4],
 279  link:RelNotes/1.5.1.3.txt[1.5.1.3],
 280  link:RelNotes/1.5.1.2.txt[1.5.1.2],
 281  link:RelNotes/1.5.1.1.txt[1.5.1.1],
 282  link:RelNotes/1.5.1.txt[1.5.1].
 283
 284* link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
 285
 286* release notes for
 287  link:RelNotes/1.5.0.7.txt[1.5.0.7],
 288  link:RelNotes/1.5.0.6.txt[1.5.0.6],
 289  link:RelNotes/1.5.0.5.txt[1.5.0.5],
 290  link:RelNotes/1.5.0.3.txt[1.5.0.3],
 291  link:RelNotes/1.5.0.2.txt[1.5.0.2],
 292  link:RelNotes/1.5.0.1.txt[1.5.0.1],
 293  link:RelNotes/1.5.0.txt[1.5.0].
 294
 295* documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 296  link:v1.3.3/git.html[1.3.3],
 297  link:v1.2.6/git.html[1.2.6],
 298  link:v1.0.13/git.html[1.0.13].
 299
 300============
 301
 302endif::stalenotes[]
 303
 304OPTIONS
 305-------
 306--version::
 307        Prints the git suite version that the 'git' program came from.
 308
 309--help::
 310        Prints the synopsis and a list of the most commonly used
 311        commands. If the option '--all' or '-a' is given then all
 312        available commands are printed. If a git command is named this
 313        option will bring up the manual page for that command.
 314+
 315Other options are available to control how the manual page is
 316displayed. See linkgit:git-help[1] for more information,
 317because `git --help ...` is converted internally into `git
 318help ...`.
 319
 320-c <name>=<value>::
 321        Pass a configuration parameter to the command. The value
 322        given will override values from configuration files.
 323        The <name> is expected in the same format as listed by
 324        'git config' (subkeys separated by dots).
 325
 326--exec-path[=<path>]::
 327        Path to wherever your core git programs are installed.
 328        This can also be controlled by setting the GIT_EXEC_PATH
 329        environment variable. If no path is given, 'git' will print
 330        the current setting and then exit.
 331
 332--html-path::
 333        Print the path, without trailing slash, where git's HTML
 334        documentation is installed and exit.
 335
 336--man-path::
 337        Print the manpath (see `man(1)`) for the man pages for
 338        this version of git and exit.
 339
 340--info-path::
 341        Print the path where the Info files documenting this
 342        version of git are installed and exit.
 343
 344-p::
 345--paginate::
 346        Pipe all output into 'less' (or if set, $PAGER) if standard
 347        output is a terminal.  This overrides the `pager.<cmd>`
 348        configuration options (see the "Configuration Mechanism" section
 349        below).
 350
 351--no-pager::
 352        Do not pipe git output into a pager.
 353
 354--git-dir=<path>::
 355        Set the path to the repository. This can also be controlled by
 356        setting the GIT_DIR environment variable. It can be an absolute
 357        path or relative path to current working directory.
 358
 359--work-tree=<path>::
 360        Set the path to the working tree. It can be an absolute path
 361        or a path relative to the current working directory.
 362        This can also be controlled by setting the GIT_WORK_TREE
 363        environment variable and the core.worktree configuration
 364        variable (see core.worktree in linkgit:git-config[1] for a
 365        more detailed discussion).
 366
 367--namespace=<path>::
 368        Set the git namespace.  See linkgit:gitnamespaces[7] for more
 369        details.  Equivalent to setting the `GIT_NAMESPACE` environment
 370        variable.
 371
 372--bare::
 373        Treat the repository as a bare repository.  If GIT_DIR
 374        environment is not set, it is set to the current working
 375        directory.
 376
 377--no-replace-objects::
 378        Do not use replacement refs to replace git objects. See
 379        linkgit:git-replace[1] for more information.
 380
 381
 382FURTHER DOCUMENTATION
 383---------------------
 384
 385See the references above to get started using git.  The following is
 386probably more detail than necessary for a first-time user.
 387
 388The link:user-manual.html#git-concepts[git concepts chapter of the
 389user-manual] and linkgit:gitcore-tutorial[7] both provide
 390introductions to the underlying git architecture.
 391
 392See linkgit:gitworkflows[7] for an overview of recommended workflows.
 393
 394See also the link:howto-index.html[howto] documents for some useful
 395examples.
 396
 397The internals are documented in the
 398link:technical/api-index.html[GIT API documentation].
 399
 400GIT COMMANDS
 401------------
 402
 403We divide git into high level ("porcelain") commands and low level
 404("plumbing") commands.
 405
 406High-level commands (porcelain)
 407-------------------------------
 408
 409We separate the porcelain commands into the main commands and some
 410ancillary user utilities.
 411
 412Main porcelain commands
 413~~~~~~~~~~~~~~~~~~~~~~~
 414
 415include::cmds-mainporcelain.txt[]
 416
 417Ancillary Commands
 418~~~~~~~~~~~~~~~~~~
 419Manipulators:
 420
 421include::cmds-ancillarymanipulators.txt[]
 422
 423Interrogators:
 424
 425include::cmds-ancillaryinterrogators.txt[]
 426
 427
 428Interacting with Others
 429~~~~~~~~~~~~~~~~~~~~~~~
 430
 431These commands are to interact with foreign SCM and with other
 432people via patch over e-mail.
 433
 434include::cmds-foreignscminterface.txt[]
 435
 436
 437Low-level commands (plumbing)
 438-----------------------------
 439
 440Although git includes its
 441own porcelain layer, its low-level commands are sufficient to support
 442development of alternative porcelains.  Developers of such porcelains
 443might start by reading about linkgit:git-update-index[1] and
 444linkgit:git-read-tree[1].
 445
 446The interface (input, output, set of options and the semantics)
 447to these low-level commands are meant to be a lot more stable
 448than Porcelain level commands, because these commands are
 449primarily for scripted use.  The interface to Porcelain commands
 450on the other hand are subject to change in order to improve the
 451end user experience.
 452
 453The following description divides
 454the low-level commands into commands that manipulate objects (in
 455the repository, index, and working tree), commands that interrogate and
 456compare objects, and commands that move objects and references between
 457repositories.
 458
 459
 460Manipulation commands
 461~~~~~~~~~~~~~~~~~~~~~
 462
 463include::cmds-plumbingmanipulators.txt[]
 464
 465
 466Interrogation commands
 467~~~~~~~~~~~~~~~~~~~~~~
 468
 469include::cmds-plumbinginterrogators.txt[]
 470
 471In general, the interrogate commands do not touch the files in
 472the working tree.
 473
 474
 475Synching repositories
 476~~~~~~~~~~~~~~~~~~~~~
 477
 478include::cmds-synchingrepositories.txt[]
 479
 480The following are helper commands used by the above; end users
 481typically do not use them directly.
 482
 483include::cmds-synchelpers.txt[]
 484
 485
 486Internal helper commands
 487~~~~~~~~~~~~~~~~~~~~~~~~
 488
 489These are internal helper commands used by other commands; end
 490users typically do not use them directly.
 491
 492include::cmds-purehelpers.txt[]
 493
 494
 495Configuration Mechanism
 496-----------------------
 497
 498Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 499is used to hold per-repository configuration options.  It is a
 500simple text file modeled after `.ini` format familiar to some
 501people.  Here is an example:
 502
 503------------
 504#
 505# A '#' or ';' character indicates a comment.
 506#
 507
 508; core variables
 509[core]
 510        ; Don't trust file modes
 511        filemode = false
 512
 513; user identity
 514[user]
 515        name = "Junio C Hamano"
 516        email = "junkio@twinsun.com"
 517
 518------------
 519
 520Various commands read from the configuration file and adjust
 521their operation accordingly.  See linkgit:git-config[1] for a
 522list.
 523
 524
 525Identifier Terminology
 526----------------------
 527<object>::
 528        Indicates the object name for any type of object.
 529
 530<blob>::
 531        Indicates a blob object name.
 532
 533<tree>::
 534        Indicates a tree object name.
 535
 536<commit>::
 537        Indicates a commit object name.
 538
 539<tree-ish>::
 540        Indicates a tree, commit or tag object name.  A
 541        command that takes a <tree-ish> argument ultimately wants to
 542        operate on a <tree> object but automatically dereferences
 543        <commit> and <tag> objects that point at a <tree>.
 544
 545<commit-ish>::
 546        Indicates a commit or tag object name.  A
 547        command that takes a <commit-ish> argument ultimately wants to
 548        operate on a <commit> object but automatically dereferences
 549        <tag> objects that point at a <commit>.
 550
 551<type>::
 552        Indicates that an object type is required.
 553        Currently one of: `blob`, `tree`, `commit`, or `tag`.
 554
 555<file>::
 556        Indicates a filename - almost always relative to the
 557        root of the tree structure `GIT_INDEX_FILE` describes.
 558
 559Symbolic Identifiers
 560--------------------
 561Any git command accepting any <object> can also use the following
 562symbolic notation:
 563
 564HEAD::
 565        indicates the head of the current branch.
 566
 567<tag>::
 568        a valid tag 'name'
 569        (i.e. a `refs/tags/<tag>` reference).
 570
 571<head>::
 572        a valid head 'name'
 573        (i.e. a `refs/heads/<head>` reference).
 574
 575For a more complete list of ways to spell object names, see
 576"SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
 577
 578
 579File/Directory Structure
 580------------------------
 581
 582Please see the linkgit:gitrepository-layout[5] document.
 583
 584Read linkgit:githooks[5] for more details about each hook.
 585
 586Higher level SCMs may provide and manage additional information in the
 587`$GIT_DIR`.
 588
 589
 590Terminology
 591-----------
 592Please see linkgit:gitglossary[7].
 593
 594
 595Environment Variables
 596---------------------
 597Various git commands use the following environment variables:
 598
 599The git Repository
 600~~~~~~~~~~~~~~~~~~
 601These environment variables apply to 'all' core git commands. Nb: it
 602is worth noting that they may be used/overridden by SCMS sitting above
 603git so take care if using Cogito etc.
 604
 605'GIT_INDEX_FILE'::
 606        This environment allows the specification of an alternate
 607        index file. If not specified, the default of `$GIT_DIR/index`
 608        is used.
 609
 610'GIT_OBJECT_DIRECTORY'::
 611        If the object storage directory is specified via this
 612        environment variable then the sha1 directories are created
 613        underneath - otherwise the default `$GIT_DIR/objects`
 614        directory is used.
 615
 616'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 617        Due to the immutable nature of git objects, old objects can be
 618        archived into shared, read-only directories. This variable
 619        specifies a ":" separated (on Windows ";" separated) list
 620        of git object directories which can be used to search for git
 621        objects. New objects will not be written to these directories.
 622
 623'GIT_DIR'::
 624        If the 'GIT_DIR' environment variable is set then it
 625        specifies a path to use instead of the default `.git`
 626        for the base of the repository.
 627
 628'GIT_WORK_TREE'::
 629        Set the path to the working tree.  The value will not be
 630        used in combination with repositories found automatically in
 631        a .git directory (i.e. $GIT_DIR is not set).
 632        This can also be controlled by the '--work-tree' command line
 633        option and the core.worktree configuration variable.
 634
 635'GIT_NAMESPACE'::
 636        Set the git namespace; see linkgit:gitnamespaces[7] for details.
 637        The '--namespace' command-line option also sets this value.
 638
 639'GIT_CEILING_DIRECTORIES'::
 640        This should be a colon-separated list of absolute paths.
 641        If set, it is a list of directories that git should not chdir
 642        up into while looking for a repository directory.
 643        It will not exclude the current working directory or
 644        a GIT_DIR set on the command line or in the environment.
 645        (Useful for excluding slow-loading network directories.)
 646
 647'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
 648        When run in a directory that does not have ".git" repository
 649        directory, git tries to find such a directory in the parent
 650        directories to find the top of the working tree, but by default it
 651        does not cross filesystem boundaries.  This environment variable
 652        can be set to true to tell git not to stop at filesystem
 653        boundaries.  Like 'GIT_CEILING_DIRECTORIES', this will not affect
 654        an explicit repository directory set via 'GIT_DIR' or on the
 655        command line.
 656
 657git Commits
 658~~~~~~~~~~~
 659'GIT_AUTHOR_NAME'::
 660'GIT_AUTHOR_EMAIL'::
 661'GIT_AUTHOR_DATE'::
 662'GIT_COMMITTER_NAME'::
 663'GIT_COMMITTER_EMAIL'::
 664'GIT_COMMITTER_DATE'::
 665'EMAIL'::
 666        see linkgit:git-commit-tree[1]
 667
 668git Diffs
 669~~~~~~~~~
 670'GIT_DIFF_OPTS'::
 671        Only valid setting is "--unified=??" or "-u??" to set the
 672        number of context lines shown when a unified diff is created.
 673        This takes precedence over any "-U" or "--unified" option
 674        value passed on the git diff command line.
 675
 676'GIT_EXTERNAL_DIFF'::
 677        When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 678        program named by it is called, instead of the diff invocation
 679        described above.  For a path that is added, removed, or modified,
 680        'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 681
 682        path old-file old-hex old-mode new-file new-hex new-mode
 683+
 684where:
 685
 686        <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 687                         contents of <old|new>,
 688        <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 689        <old|new>-mode:: are the octal representation of the file modes.
 690+
 691The file parameters can point at the user's working file
 692(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 693when a new file is added), or a temporary file (e.g. `old-file` in the
 694index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 695temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 696+
 697For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 698parameter, <path>.
 699
 700other
 701~~~~~
 702'GIT_MERGE_VERBOSITY'::
 703        A number controlling the amount of output shown by
 704        the recursive merge strategy.  Overrides merge.verbosity.
 705        See linkgit:git-merge[1]
 706
 707'GIT_PAGER'::
 708        This environment variable overrides `$PAGER`. If it is set
 709        to an empty string or to the value "cat", git will not launch
 710        a pager.  See also the `core.pager` option in
 711        linkgit:git-config[1].
 712
 713'GIT_SSH'::
 714        If this environment variable is set then 'git fetch'
 715        and 'git push' will use this command instead
 716        of 'ssh' when they need to connect to a remote system.
 717        The '$GIT_SSH' command will be given exactly two arguments:
 718        the 'username@host' (or just 'host') from the URL and the
 719        shell command to execute on that remote system.
 720+
 721To pass options to the program that you want to list in GIT_SSH
 722you will need to wrap the program and options into a shell script,
 723then set GIT_SSH to refer to the shell script.
 724+
 725Usually it is easier to configure any desired options through your
 726personal `.ssh/config` file.  Please consult your ssh documentation
 727for further details.
 728
 729'GIT_ASKPASS'::
 730        If this environment variable is set, then git commands which need to
 731        acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
 732        will call this program with a suitable prompt as command line argument
 733        and read the password from its STDOUT. See also the 'core.askpass'
 734        option in linkgit:git-config[1].
 735
 736'GIT_FLUSH'::
 737        If this environment variable is set to "1", then commands such
 738        as 'git blame' (in incremental mode), 'git rev-list', 'git log',
 739        and 'git whatchanged' will force a flush of the output stream
 740        after each commit-oriented record have been flushed.   If this
 741        variable is set to "0", the output of these commands will be done
 742        using completely buffered I/O.   If this environment variable is
 743        not set, git will choose buffered or record-oriented flushing
 744        based on whether stdout appears to be redirected to a file or not.
 745
 746'GIT_TRACE'::
 747        If this variable is set to "1", "2" or "true" (comparison
 748        is case insensitive), git will print `trace:` messages on
 749        stderr telling about alias expansion, built-in command
 750        execution and external command execution.
 751        If this variable is set to an integer value greater than 1
 752        and lower than 10 (strictly) then git will interpret this
 753        value as an open file descriptor and will try to write the
 754        trace messages into this file descriptor.
 755        Alternatively, if this variable is set to an absolute path
 756        (starting with a '/' character), git will interpret this
 757        as a file path and will try to write the trace messages
 758        into it.
 759
 760Discussion[[Discussion]]
 761------------------------
 762
 763More detail on the following is available from the
 764link:user-manual.html#git-concepts[git concepts chapter of the
 765user-manual] and linkgit:gitcore-tutorial[7].
 766
 767A git project normally consists of a working directory with a ".git"
 768subdirectory at the top level.  The .git directory contains, among other
 769things, a compressed object database representing the complete history
 770of the project, an "index" file which links that history to the current
 771contents of the working tree, and named pointers into that history such
 772as tags and branch heads.
 773
 774The object database contains objects of three main types: blobs, which
 775hold file data; trees, which point to blobs and other trees to build up
 776directory hierarchies; and commits, which each reference a single tree
 777and some number of parent commits.
 778
 779The commit, equivalent to what other systems call a "changeset" or
 780"version", represents a step in the project's history, and each parent
 781represents an immediately preceding step.  Commits with more than one
 782parent represent merges of independent lines of development.
 783
 784All objects are named by the SHA1 hash of their contents, normally
 785written as a string of 40 hex digits.  Such names are globally unique.
 786The entire history leading up to a commit can be vouched for by signing
 787just that commit.  A fourth object type, the tag, is provided for this
 788purpose.
 789
 790When first created, objects are stored in individual files, but for
 791efficiency may later be compressed together into "pack files".
 792
 793Named pointers called refs mark interesting points in history.  A ref
 794may contain the SHA1 name of an object or the name of another ref.  Refs
 795with names beginning `ref/head/` contain the SHA1 name of the most
 796recent commit (or "head") of a branch under development.  SHA1 names of
 797tags of interest are stored under `ref/tags/`.  A special ref named
 798`HEAD` contains the name of the currently checked-out branch.
 799
 800The index file is initialized with a list of all paths and, for each
 801path, a blob object and a set of attributes.  The blob object represents
 802the contents of the file as of the head of the current branch.  The
 803attributes (last modified time, size, etc.) are taken from the
 804corresponding file in the working tree.  Subsequent changes to the
 805working tree can be found by comparing these attributes.  The index may
 806be updated with new content, and new commits may be created from the
 807content stored in the index.
 808
 809The index is also capable of storing multiple entries (called "stages")
 810for a given pathname.  These stages are used to hold the various
 811unmerged version of a file when a merge is in progress.
 812
 813Authors
 814-------
 815Git was started by Linus Torvalds, and is currently maintained by Junio
 816C Hamano. Numerous contributions have come from the git mailing list
 817<git@vger.kernel.org>. For a more complete list of contributors, see
 818http://git-scm.com/about. If you have a clone of git.git itself, the
 819output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
 820the authors for specific parts of the project.
 821
 822Reporting Bugs
 823--------------
 824
 825Report bugs to the Git mailing list <git@vger.kernel.org> where the
 826development and maintenance is primarily done.  You do not have to be
 827subscribed to the list to send a message there.
 828
 829SEE ALSO
 830--------
 831linkgit:gittutorial[7], linkgit:gittutorial-2[7],
 832link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
 833linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
 834linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
 835linkgit:gitworkflows[7]
 836
 837GIT
 838---
 839Part of the linkgit:git[1] suite