Documentation / git.txton commit Merge branch 'jw/doc-commit-title' (d6e32f6)
   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
  26commands.  The link:user-manual.html[Git User's Manual] has a more
  27in-depth introduction.
  28
  29After you mastered the basic concepts, you can come back to this
  30page to learn what commands git offers.  You can learn more about
  31individual git commands with "git help command".  linkgit:gitcli[7]
  32manual page gives you an overview of the command line command syntax.
  33
  34Formatted and hyperlinked version of the latest git documentation
  35can be viewed at `http://git-htmldocs.googlecode.com/git/git.html`.
  36
  37ifdef::stalenotes[]
  38[NOTE]
  39============
  40
  41You are reading the documentation for the latest (possibly
  42unreleased) version of git, that is available from 'master'
  43branch of the `git.git` repository.
  44Documentation 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
 335endif::stalenotes[]
 336
 337OPTIONS
 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+
 348Other options are available to control how the manual page is
 349displayed. See linkgit:git-help[1] for more information,
 350because `git --help ...` is converted internally into `git
 351help ...`.
 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
 415GIT COMMANDS
 416------------
 417
 418We divide git into high level ("porcelain") commands and low level
 419("plumbing") commands.
 420
 421High-level commands (porcelain)
 422-------------------------------
 423
 424We separate the porcelain commands into the main commands and some
 425ancillary user utilities.
 426
 427Main porcelain commands
 428~~~~~~~~~~~~~~~~~~~~~~~
 429
 430include::cmds-mainporcelain.txt[]
 431
 432Ancillary Commands
 433~~~~~~~~~~~~~~~~~~
 434Manipulators:
 435
 436include::cmds-ancillarymanipulators.txt[]
 437
 438Interrogators:
 439
 440include::cmds-ancillaryinterrogators.txt[]
 441
 442
 443Interacting with Others
 444~~~~~~~~~~~~~~~~~~~~~~~
 445
 446These commands are to interact with foreign SCM and with other
 447people via patch over e-mail.
 448
 449include::cmds-foreignscminterface.txt[]
 450
 451
 452Low-level commands (plumbing)
 453-----------------------------
 454
 455Although git includes its
 456own porcelain layer, its low-level commands are sufficient to support
 457development of alternative porcelains.  Developers of such porcelains
 458might start by reading about linkgit:git-update-index[1] and
 459linkgit:git-read-tree[1].
 460
 461The interface (input, output, set of options and the semantics)
 462to these low-level commands are meant to be a lot more stable
 463than Porcelain level commands, because these commands are
 464primarily for scripted use.  The interface to Porcelain commands
 465on the other hand are subject to change in order to improve the
 466end user experience.
 467
 468The following description divides
 469the low-level commands into commands that manipulate objects (in
 470the repository, index, and working tree), commands that interrogate and
 471compare objects, and commands that move objects and references between
 472repositories.
 473
 474
 475Manipulation commands
 476~~~~~~~~~~~~~~~~~~~~~
 477
 478include::cmds-plumbingmanipulators.txt[]
 479
 480
 481Interrogation commands
 482~~~~~~~~~~~~~~~~~~~~~~
 483
 484include::cmds-plumbinginterrogators.txt[]
 485
 486In general, the interrogate commands do not touch the files in
 487the working tree.
 488
 489
 490Synching repositories
 491~~~~~~~~~~~~~~~~~~~~~
 492
 493include::cmds-synchingrepositories.txt[]
 494
 495The following are helper commands used by the above; end users
 496typically do not use them directly.
 497
 498include::cmds-synchelpers.txt[]
 499
 500
 501Internal helper commands
 502~~~~~~~~~~~~~~~~~~~~~~~~
 503
 504These are internal helper commands used by other commands; end
 505users typically do not use them directly.
 506
 507include::cmds-purehelpers.txt[]
 508
 509
 510Configuration Mechanism
 511-----------------------
 512
 513Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 514is used to hold per-repository configuration options.  It is a
 515simple text file modeled after `.ini` format familiar to some
 516people.  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
 535Various commands read from the configuration file and adjust
 536their operation accordingly.  See linkgit:git-config[1] for a
 537list.
 538
 539
 540Identifier 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
 574Symbolic Identifiers
 575--------------------
 576Any git command accepting any <object> can also use the following
 577symbolic notation:
 578
 579HEAD::
 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
 590For a more complete list of ways to spell object names, see
 591"SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
 592
 593
 594File/Directory Structure
 595------------------------
 596
 597Please see the linkgit:gitrepository-layout[5] document.
 598
 599Read linkgit:githooks[5] for more details about each hook.
 600
 601Higher level SCMs may provide and manage additional information in the
 602`$GIT_DIR`.
 603
 604
 605Terminology
 606-----------
 607Please see linkgit:gitglossary[7].
 608
 609
 610Environment Variables
 611---------------------
 612Various git commands use the following environment variables:
 613
 614The git Repository
 615~~~~~~~~~~~~~~~~~~
 616These environment variables apply to 'all' core git commands. Nb: it
 617is worth noting that they may be used/overridden by SCMS sitting above
 618git 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
 672git 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
 683git 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+
 699where:
 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+
 706The 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`
 708when a new file is added), or a temporary file (e.g. `old-file` in the
 709index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 710temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 711+
 712For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 713parameter, <path>.
 714
 715other
 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+
 742To pass options to the program that you want to list in GIT_SSH
 743you will need to wrap the program and options into a shell script,
 744then set GIT_SSH to refer to the shell script.
 745+
 746Usually it is easier to configure any desired options through your
 747personal `.ssh/config` file.  Please consult your ssh documentation
 748for 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
 781Discussion[[Discussion]]
 782------------------------
 783
 784More detail on the following is available from the
 785link:user-manual.html#git-concepts[git concepts chapter of the
 786user-manual] and linkgit:gitcore-tutorial[7].
 787
 788A git project normally consists of a working directory with a ".git"
 789subdirectory at the top level.  The .git directory contains, among other
 790things, a compressed object database representing the complete history
 791of the project, an "index" file which links that history to the current
 792contents of the working tree, and named pointers into that history such
 793as tags and branch heads.
 794
 795The object database contains objects of three main types: blobs, which
 796hold file data; trees, which point to blobs and other trees to build up
 797directory hierarchies; and commits, which each reference a single tree
 798and some number of parent commits.
 799
 800The commit, equivalent to what other systems call a "changeset" or
 801"version", represents a step in the project's history, and each parent
 802represents an immediately preceding step.  Commits with more than one
 803parent represent merges of independent lines of development.
 804
 805All objects are named by the SHA1 hash of their contents, normally
 806written as a string of 40 hex digits.  Such names are globally unique.
 807The entire history leading up to a commit can be vouched for by signing
 808just that commit.  A fourth object type, the tag, is provided for this
 809purpose.
 810
 811When first created, objects are stored in individual files, but for
 812efficiency may later be compressed together into "pack files".
 813
 814Named pointers called refs mark interesting points in history.  A ref
 815may contain the SHA1 name of an object or the name of another ref.  Refs
 816with names beginning `ref/head/` contain the SHA1 name of the most
 817recent commit (or "head") of a branch under development.  SHA1 names of
 818tags of interest are stored under `ref/tags/`.  A special ref named
 819`HEAD` contains the name of the currently checked-out branch.
 820
 821The index file is initialized with a list of all paths and, for each
 822path, a blob object and a set of attributes.  The blob object represents
 823the contents of the file as of the head of the current branch.  The
 824attributes (last modified time, size, etc.) are taken from the
 825corresponding file in the working tree.  Subsequent changes to the
 826working tree can be found by comparing these attributes.  The index may
 827be updated with new content, and new commits may be created from the
 828content stored in the index.
 829
 830The index is also capable of storing multiple entries (called "stages")
 831for a given pathname.  These stages are used to hold the various
 832unmerged version of a file when a merge is in progress.
 833
 834FURTHER DOCUMENTATION
 835---------------------
 836
 837See the references in the "description" section to get started
 838using git.  The following is probably more detail than necessary
 839for a first-time user.
 840
 841The link:user-manual.html#git-concepts[git concepts chapter of the
 842user-manual] and linkgit:gitcore-tutorial[7] both provide
 843introductions to the underlying git architecture.
 844
 845See linkgit:gitworkflows[7] for an overview of recommended workflows.
 846
 847See also the link:howto-index.html[howto] documents for some useful
 848examples.
 849
 850The internals are documented in the
 851link:technical/api-index.html[GIT API documentation].
 852
 853Users migrating from CVS may also want to
 854read linkgit:gitcvs-migration[7].
 855
 856
 857Authors
 858-------
 859Git was started by Linus Torvalds, and is currently maintained by Junio
 860C Hamano. Numerous contributions have come from the git mailing list
 861<git@vger.kernel.org>. For a more complete list of contributors, see
 862http://git-scm.com/about. If you have a clone of git.git itself, the
 863output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
 864the authors for specific parts of the project.
 865
 866Reporting Bugs
 867--------------
 868
 869Report bugs to the Git mailing list <git@vger.kernel.org> where the
 870development and maintenance is primarily done.  You do not have to be
 871subscribed to the list to send a message there.
 872
 873SEE ALSO
 874--------
 875linkgit:gittutorial[7], linkgit:gittutorial-2[7],
 876link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
 877linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
 878linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
 879linkgit:gitworkflows[7]
 880
 881GIT
 882---
 883Part of the linkgit:git[1] suite