Documentation / git.txton commit daemon: handle freopen() failure (c569b1f)
   1git(1)
   2======
   3
   4NAME
   5----
   6git - the stupid content tracker
   7
   8
   9SYNOPSIS
  10--------
  11[verse]
  12'git' [--version] [--exec-path[=GIT_EXEC_PATH]]
  13    [-p|--paginate|--no-pager]
  14    [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE]
  15    [--help] COMMAND [ARGS]
  16
  17DESCRIPTION
  18-----------
  19Git is a fast, scalable, distributed revision control system with an
  20unusually rich command set that provides both high-level operations
  21and full access to internals.
  22
  23See linkgit:gittutorial[7] to get started, then see
  24link:everyday.html[Everyday Git] for a useful minimum set of commands, and
  25"man git-commandname" for documentation of each command.  CVS users may
  26also want to read linkgit:gitcvs-migration[7].  See
  27the link:user-manual.html[Git User's Manual] for a more in-depth
  28introduction.
  29
  30The COMMAND is either a name of a Git command (see below) or an alias
  31as defined in the configuration file (see linkgit:git-config[1]).
  32
  33Formatted and hyperlinked version of the latest git
  34documentation can be viewed at
  35`http://www.kernel.org/pub/software/scm/git/docs/`.
  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:v1.6.1/git.html[documentation for release 1.6.1]
  47
  48* release notes for
  49  link:RelNotes-1.6.1.txt[1.6.1].
  50
  51* link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
  52
  53* release notes for
  54  link:RelNotes-1.6.0.6.txt[1.6.0.6],
  55  link:RelNotes-1.6.0.5.txt[1.6.0.5],
  56  link:RelNotes-1.6.0.4.txt[1.6.0.4],
  57  link:RelNotes-1.6.0.3.txt[1.6.0.3],
  58  link:RelNotes-1.6.0.2.txt[1.6.0.2],
  59  link:RelNotes-1.6.0.1.txt[1.6.0.1],
  60  link:RelNotes-1.6.0.txt[1.6.0].
  61
  62* link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
  63
  64* release notes for
  65  link:RelNotes-1.5.6.6.txt[1.5.6.6],
  66  link:RelNotes-1.5.6.5.txt[1.5.6.5],
  67  link:RelNotes-1.5.6.4.txt[1.5.6.4],
  68  link:RelNotes-1.5.6.3.txt[1.5.6.3],
  69  link:RelNotes-1.5.6.2.txt[1.5.6.2],
  70  link:RelNotes-1.5.6.1.txt[1.5.6.1],
  71  link:RelNotes-1.5.6.txt[1.5.6].
  72
  73* link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
  74
  75* release notes for
  76  link:RelNotes-1.5.5.6.txt[1.5.5.6],
  77  link:RelNotes-1.5.5.5.txt[1.5.5.5],
  78  link:RelNotes-1.5.5.4.txt[1.5.5.4],
  79  link:RelNotes-1.5.5.3.txt[1.5.5.3],
  80  link:RelNotes-1.5.5.2.txt[1.5.5.2],
  81  link:RelNotes-1.5.5.1.txt[1.5.5.1],
  82  link:RelNotes-1.5.5.txt[1.5.5].
  83
  84* link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
  85
  86* release notes for
  87  link:RelNotes-1.5.4.7.txt[1.5.4.7],
  88  link:RelNotes-1.5.4.6.txt[1.5.4.6],
  89  link:RelNotes-1.5.4.5.txt[1.5.4.5],
  90  link:RelNotes-1.5.4.4.txt[1.5.4.4],
  91  link:RelNotes-1.5.4.3.txt[1.5.4.3],
  92  link:RelNotes-1.5.4.2.txt[1.5.4.2],
  93  link:RelNotes-1.5.4.1.txt[1.5.4.1],
  94  link:RelNotes-1.5.4.txt[1.5.4].
  95
  96* link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
  97
  98* release notes for
  99  link:RelNotes-1.5.3.8.txt[1.5.3.8],
 100  link:RelNotes-1.5.3.7.txt[1.5.3.7],
 101  link:RelNotes-1.5.3.6.txt[1.5.3.6],
 102  link:RelNotes-1.5.3.5.txt[1.5.3.5],
 103  link:RelNotes-1.5.3.4.txt[1.5.3.4],
 104  link:RelNotes-1.5.3.3.txt[1.5.3.3],
 105  link:RelNotes-1.5.3.2.txt[1.5.3.2],
 106  link:RelNotes-1.5.3.1.txt[1.5.3.1],
 107  link:RelNotes-1.5.3.txt[1.5.3].
 108
 109* link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
 110
 111* release notes for
 112  link:RelNotes-1.5.2.5.txt[1.5.2.5],
 113  link:RelNotes-1.5.2.4.txt[1.5.2.4],
 114  link:RelNotes-1.5.2.3.txt[1.5.2.3],
 115  link:RelNotes-1.5.2.2.txt[1.5.2.2],
 116  link:RelNotes-1.5.2.1.txt[1.5.2.1],
 117  link:RelNotes-1.5.2.txt[1.5.2].
 118
 119* link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
 120
 121* release notes for
 122  link:RelNotes-1.5.1.6.txt[1.5.1.6],
 123  link:RelNotes-1.5.1.5.txt[1.5.1.5],
 124  link:RelNotes-1.5.1.4.txt[1.5.1.4],
 125  link:RelNotes-1.5.1.3.txt[1.5.1.3],
 126  link:RelNotes-1.5.1.2.txt[1.5.1.2],
 127  link:RelNotes-1.5.1.1.txt[1.5.1.1],
 128  link:RelNotes-1.5.1.txt[1.5.1].
 129
 130* link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
 131
 132* release notes for
 133  link:RelNotes-1.5.0.7.txt[1.5.0.7],
 134  link:RelNotes-1.5.0.6.txt[1.5.0.6],
 135  link:RelNotes-1.5.0.5.txt[1.5.0.5],
 136  link:RelNotes-1.5.0.3.txt[1.5.0.3],
 137  link:RelNotes-1.5.0.2.txt[1.5.0.2],
 138  link:RelNotes-1.5.0.1.txt[1.5.0.1],
 139  link:RelNotes-1.5.0.txt[1.5.0].
 140
 141* documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 142  link:v1.3.3/git.html[1.3.3],
 143  link:v1.2.6/git.html[1.2.6],
 144  link:v1.0.13/git.html[1.0.13].
 145
 146============
 147
 148endif::stalenotes[]
 149
 150OPTIONS
 151-------
 152--version::
 153        Prints the git suite version that the 'git' program came from.
 154
 155--help::
 156        Prints the synopsis and a list of the most commonly used
 157        commands. If the option '--all' or '-a' is given then all
 158        available commands are printed. If a git command is named this
 159        option will bring up the manual page for that command.
 160+
 161Other options are available to control how the manual page is
 162displayed. See linkgit:git-help[1] for more information,
 163because `git --help ...` is converted internally into `git
 164help ...`.
 165
 166--exec-path::
 167        Path to wherever your core git programs are installed.
 168        This can also be controlled by setting the GIT_EXEC_PATH
 169        environment variable. If no path is given, 'git' will print
 170        the current setting and then exit.
 171
 172-p::
 173--paginate::
 174        Pipe all output into 'less' (or if set, $PAGER).
 175
 176--no-pager::
 177        Do not pipe git output into a pager.
 178
 179--git-dir=<path>::
 180        Set the path to the repository. This can also be controlled by
 181        setting the GIT_DIR environment variable. It can be an absolute
 182        path or relative path to current working directory.
 183
 184--work-tree=<path>::
 185        Set the path to the working tree.  The value will not be
 186        used in combination with repositories found automatically in
 187        a .git directory (i.e. $GIT_DIR is not set).
 188        This can also be controlled by setting the GIT_WORK_TREE
 189        environment variable and the core.worktree configuration
 190        variable. It can be an absolute path or relative path to
 191        the directory specified by --git-dir or GIT_DIR.
 192        Note: If --git-dir or GIT_DIR are specified but none of
 193        --work-tree, GIT_WORK_TREE and core.worktree is specified,
 194        the current working directory is regarded as the top directory
 195        of your working tree.
 196
 197--bare::
 198        Treat the repository as a bare repository.  If GIT_DIR
 199        environment is not set, it is set to the current working
 200        directory.
 201
 202
 203FURTHER DOCUMENTATION
 204---------------------
 205
 206See the references above to get started using git.  The following is
 207probably more detail than necessary for a first-time user.
 208
 209The link:user-manual.html#git-concepts[git concepts chapter of the
 210user-manual] and linkgit:gitcore-tutorial[7] both provide
 211introductions to the underlying git architecture.
 212
 213See also the link:howto-index.html[howto] documents for some useful
 214examples.
 215
 216The internals are documented in the
 217link:technical/api-index.html[GIT API documentation].
 218
 219GIT COMMANDS
 220------------
 221
 222We divide git into high level ("porcelain") commands and low level
 223("plumbing") commands.
 224
 225High-level commands (porcelain)
 226-------------------------------
 227
 228We separate the porcelain commands into the main commands and some
 229ancillary user utilities.
 230
 231Main porcelain commands
 232~~~~~~~~~~~~~~~~~~~~~~~
 233
 234include::cmds-mainporcelain.txt[]
 235
 236Ancillary Commands
 237~~~~~~~~~~~~~~~~~~
 238Manipulators:
 239
 240include::cmds-ancillarymanipulators.txt[]
 241
 242Interrogators:
 243
 244include::cmds-ancillaryinterrogators.txt[]
 245
 246
 247Interacting with Others
 248~~~~~~~~~~~~~~~~~~~~~~~
 249
 250These commands are to interact with foreign SCM and with other
 251people via patch over e-mail.
 252
 253include::cmds-foreignscminterface.txt[]
 254
 255
 256Low-level commands (plumbing)
 257-----------------------------
 258
 259Although git includes its
 260own porcelain layer, its low-level commands are sufficient to support
 261development of alternative porcelains.  Developers of such porcelains
 262might start by reading about linkgit:git-update-index[1] and
 263linkgit:git-read-tree[1].
 264
 265The interface (input, output, set of options and the semantics)
 266to these low-level commands are meant to be a lot more stable
 267than Porcelain level commands, because these commands are
 268primarily for scripted use.  The interface to Porcelain commands
 269on the other hand are subject to change in order to improve the
 270end user experience.
 271
 272The following description divides
 273the low-level commands into commands that manipulate objects (in
 274the repository, index, and working tree), commands that interrogate and
 275compare objects, and commands that move objects and references between
 276repositories.
 277
 278
 279Manipulation commands
 280~~~~~~~~~~~~~~~~~~~~~
 281
 282include::cmds-plumbingmanipulators.txt[]
 283
 284
 285Interrogation commands
 286~~~~~~~~~~~~~~~~~~~~~~
 287
 288include::cmds-plumbinginterrogators.txt[]
 289
 290In general, the interrogate commands do not touch the files in
 291the working tree.
 292
 293
 294Synching repositories
 295~~~~~~~~~~~~~~~~~~~~~
 296
 297include::cmds-synchingrepositories.txt[]
 298
 299The following are helper programs used by the above; end users
 300typically do not use them directly.
 301
 302include::cmds-synchelpers.txt[]
 303
 304
 305Internal helper commands
 306~~~~~~~~~~~~~~~~~~~~~~~~
 307
 308These are internal helper commands used by other commands; end
 309users typically do not use them directly.
 310
 311include::cmds-purehelpers.txt[]
 312
 313
 314Configuration Mechanism
 315-----------------------
 316
 317Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 318is used to hold per-repository configuration options.  It is a
 319simple text file modeled after `.ini` format familiar to some
 320people.  Here is an example:
 321
 322------------
 323#
 324# A '#' or ';' character indicates a comment.
 325#
 326
 327; core variables
 328[core]
 329        ; Don't trust file modes
 330        filemode = false
 331
 332; user identity
 333[user]
 334        name = "Junio C Hamano"
 335        email = "junkio@twinsun.com"
 336
 337------------
 338
 339Various commands read from the configuration file and adjust
 340their operation accordingly.
 341
 342
 343Identifier Terminology
 344----------------------
 345<object>::
 346        Indicates the object name for any type of object.
 347
 348<blob>::
 349        Indicates a blob object name.
 350
 351<tree>::
 352        Indicates a tree object name.
 353
 354<commit>::
 355        Indicates a commit object name.
 356
 357<tree-ish>::
 358        Indicates a tree, commit or tag object name.  A
 359        command that takes a <tree-ish> argument ultimately wants to
 360        operate on a <tree> object but automatically dereferences
 361        <commit> and <tag> objects that point at a <tree>.
 362
 363<commit-ish>::
 364        Indicates a commit or tag object name.  A
 365        command that takes a <commit-ish> argument ultimately wants to
 366        operate on a <commit> object but automatically dereferences
 367        <tag> objects that point at a <commit>.
 368
 369<type>::
 370        Indicates that an object type is required.
 371        Currently one of: `blob`, `tree`, `commit`, or `tag`.
 372
 373<file>::
 374        Indicates a filename - almost always relative to the
 375        root of the tree structure `GIT_INDEX_FILE` describes.
 376
 377Symbolic Identifiers
 378--------------------
 379Any git command accepting any <object> can also use the following
 380symbolic notation:
 381
 382HEAD::
 383        indicates the head of the current branch (i.e. the
 384        contents of `$GIT_DIR/HEAD`).
 385
 386<tag>::
 387        a valid tag 'name'
 388        (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`).
 389
 390<head>::
 391        a valid head 'name'
 392        (i.e. the contents of `$GIT_DIR/refs/heads/<head>`).
 393
 394For a more complete list of ways to spell object names, see
 395"SPECIFYING REVISIONS" section in linkgit:git-rev-parse[1].
 396
 397
 398File/Directory Structure
 399------------------------
 400
 401Please see the linkgit:gitrepository-layout[5] document.
 402
 403Read linkgit:githooks[5] for more details about each hook.
 404
 405Higher level SCMs may provide and manage additional information in the
 406`$GIT_DIR`.
 407
 408
 409Terminology
 410-----------
 411Please see linkgit:gitglossary[7].
 412
 413
 414Environment Variables
 415---------------------
 416Various git commands use the following environment variables:
 417
 418The git Repository
 419~~~~~~~~~~~~~~~~~~
 420These environment variables apply to 'all' core git commands. Nb: it
 421is worth noting that they may be used/overridden by SCMS sitting above
 422git so take care if using Cogito etc.
 423
 424'GIT_INDEX_FILE'::
 425        This environment allows the specification of an alternate
 426        index file. If not specified, the default of `$GIT_DIR/index`
 427        is used.
 428
 429'GIT_OBJECT_DIRECTORY'::
 430        If the object storage directory is specified via this
 431        environment variable then the sha1 directories are created
 432        underneath - otherwise the default `$GIT_DIR/objects`
 433        directory is used.
 434
 435'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 436        Due to the immutable nature of git objects, old objects can be
 437        archived into shared, read-only directories. This variable
 438        specifies a ":" separated (on Windows ";" separated) list
 439        of git object directories which can be used to search for git
 440        objects. New objects will not be written to these directories.
 441
 442'GIT_DIR'::
 443        If the 'GIT_DIR' environment variable is set then it
 444        specifies a path to use instead of the default `.git`
 445        for the base of the repository.
 446
 447'GIT_WORK_TREE'::
 448        Set the path to the working tree.  The value will not be
 449        used in combination with repositories found automatically in
 450        a .git directory (i.e. $GIT_DIR is not set).
 451        This can also be controlled by the '--work-tree' command line
 452        option and the core.worktree configuration variable.
 453
 454'GIT_CEILING_DIRECTORIES'::
 455        This should be a colon-separated list of absolute paths.
 456        If set, it is a list of directories that git should not chdir
 457        up into while looking for a repository directory.
 458        It will not exclude the current working directory or
 459        a GIT_DIR set on the command line or in the environment.
 460        (Useful for excluding slow-loading network directories.)
 461
 462git Commits
 463~~~~~~~~~~~
 464'GIT_AUTHOR_NAME'::
 465'GIT_AUTHOR_EMAIL'::
 466'GIT_AUTHOR_DATE'::
 467'GIT_COMMITTER_NAME'::
 468'GIT_COMMITTER_EMAIL'::
 469'GIT_COMMITTER_DATE'::
 470'EMAIL'::
 471        see linkgit:git-commit-tree[1]
 472
 473git Diffs
 474~~~~~~~~~
 475'GIT_DIFF_OPTS'::
 476        Only valid setting is "--unified=??" or "-u??" to set the
 477        number of context lines shown when a unified diff is created.
 478        This takes precedence over any "-U" or "--unified" option
 479        value passed on the git diff command line.
 480
 481'GIT_EXTERNAL_DIFF'::
 482        When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 483        program named by it is called, instead of the diff invocation
 484        described above.  For a path that is added, removed, or modified,
 485        'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 486
 487        path old-file old-hex old-mode new-file new-hex new-mode
 488+
 489where:
 490
 491        <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 492                         contents of <old|new>,
 493        <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 494        <old|new>-mode:: are the octal representation of the file modes.
 495
 496+
 497The file parameters can point at the user's working file
 498(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 499when a new file is added), or a temporary file (e.g. `old-file` in the
 500index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 501temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 502+
 503For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 504parameter, <path>.
 505
 506other
 507~~~~~
 508'GIT_MERGE_VERBOSITY'::
 509        A number controlling the amount of output shown by
 510        the recursive merge strategy.  Overrides merge.verbosity.
 511        See linkgit:git-merge[1]
 512
 513'GIT_PAGER'::
 514        This environment variable overrides `$PAGER`. If it is set
 515        to an empty string or to the value "cat", git will not launch
 516        a pager.  See also the `core.pager` option in
 517        linkgit:git-config[1].
 518
 519'GIT_SSH'::
 520        If this environment variable is set then 'git-fetch'
 521        and 'git-push' will use this command instead
 522        of 'ssh' when they need to connect to a remote system.
 523        The '$GIT_SSH' command will be given exactly two arguments:
 524        the 'username@host' (or just 'host') from the URL and the
 525        shell command to execute on that remote system.
 526+
 527To pass options to the program that you want to list in GIT_SSH
 528you will need to wrap the program and options into a shell script,
 529then set GIT_SSH to refer to the shell script.
 530+
 531Usually it is easier to configure any desired options through your
 532personal `.ssh/config` file.  Please consult your ssh documentation
 533for further details.
 534
 535'GIT_FLUSH'::
 536        If this environment variable is set to "1", then commands such
 537        as 'git-blame' (in incremental mode), 'git-rev-list', 'git-log',
 538        and 'git-whatchanged' will force a flush of the output stream
 539        after each commit-oriented record have been flushed.   If this
 540        variable is set to "0", the output of these commands will be done
 541        using completely buffered I/O.   If this environment variable is
 542        not set, git will choose buffered or record-oriented flushing
 543        based on whether stdout appears to be redirected to a file or not.
 544
 545'GIT_TRACE'::
 546        If this variable is set to "1", "2" or "true" (comparison
 547        is case insensitive), git will print `trace:` messages on
 548        stderr telling about alias expansion, built-in command
 549        execution and external command execution.
 550        If this variable is set to an integer value greater than 1
 551        and lower than 10 (strictly) then git will interpret this
 552        value as an open file descriptor and will try to write the
 553        trace messages into this file descriptor.
 554        Alternatively, if this variable is set to an absolute path
 555        (starting with a '/' character), git will interpret this
 556        as a file path and will try to write the trace messages
 557        into it.
 558
 559Discussion[[Discussion]]
 560------------------------
 561
 562More detail on the following is available from the
 563link:user-manual.html#git-concepts[git concepts chapter of the
 564user-manual] and linkgit:gitcore-tutorial[7].
 565
 566A git project normally consists of a working directory with a ".git"
 567subdirectory at the top level.  The .git directory contains, among other
 568things, a compressed object database representing the complete history
 569of the project, an "index" file which links that history to the current
 570contents of the working tree, and named pointers into that history such
 571as tags and branch heads.
 572
 573The object database contains objects of three main types: blobs, which
 574hold file data; trees, which point to blobs and other trees to build up
 575directory hierarchies; and commits, which each reference a single tree
 576and some number of parent commits.
 577
 578The commit, equivalent to what other systems call a "changeset" or
 579"version", represents a step in the project's history, and each parent
 580represents an immediately preceding step.  Commits with more than one
 581parent represent merges of independent lines of development.
 582
 583All objects are named by the SHA1 hash of their contents, normally
 584written as a string of 40 hex digits.  Such names are globally unique.
 585The entire history leading up to a commit can be vouched for by signing
 586just that commit.  A fourth object type, the tag, is provided for this
 587purpose.
 588
 589When first created, objects are stored in individual files, but for
 590efficiency may later be compressed together into "pack files".
 591
 592Named pointers called refs mark interesting points in history.  A ref
 593may contain the SHA1 name of an object or the name of another ref.  Refs
 594with names beginning `ref/head/` contain the SHA1 name of the most
 595recent commit (or "head") of a branch under development.  SHA1 names of
 596tags of interest are stored under `ref/tags/`.  A special ref named
 597`HEAD` contains the name of the currently checked-out branch.
 598
 599The index file is initialized with a list of all paths and, for each
 600path, a blob object and a set of attributes.  The blob object represents
 601the contents of the file as of the head of the current branch.  The
 602attributes (last modified time, size, etc.) are taken from the
 603corresponding file in the working tree.  Subsequent changes to the
 604working tree can be found by comparing these attributes.  The index may
 605be updated with new content, and new commits may be created from the
 606content stored in the index.
 607
 608The index is also capable of storing multiple entries (called "stages")
 609for a given pathname.  These stages are used to hold the various
 610unmerged version of a file when a merge is in progress.
 611
 612Authors
 613-------
 614* git's founding father is Linus Torvalds <torvalds@osdl.org>.
 615* The current git nurse is Junio C Hamano <gitster@pobox.com>.
 616* The git potty was written by Andreas Ericsson <ae@op5.se>.
 617* General upbringing is handled by the git-list <git@vger.kernel.org>.
 618
 619Documentation
 620--------------
 621The documentation for git suite was started by David Greaves
 622<david@dgreaves.com>, and later enhanced greatly by the
 623contributors on the git-list <git@vger.kernel.org>.
 624
 625SEE ALSO
 626--------
 627linkgit:gittutorial[7], linkgit:gittutorial-2[7],
 628link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
 629linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
 630linkgit:gitcli[7], link:user-manual.html[The Git User's Manual]
 631
 632GIT
 633---
 634Part of the linkgit:git[1] suite