Documentation / git.txton commit Merge branch 'maint-1.5.4' into maint (6233a52)
   1git(7)
   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 this link:tutorial.html[tutorial] 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 link:cvs-migration.html[CVS migration].  See
  27link: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:v1.5.5/git.html[documentation for release 1.5.5]
  47
  48* release notes for
  49  link:RelNotes-1.5.5.1.txt[1.5.5.1],
  50  link:RelNotes-1.5.5.txt[1.5.5].
  51
  52* link:v1.5.5.1/git.html[documentation for release 1.5.5.1]
  53
  54* link:v1.5.4.5/git.html[documentation for release 1.5.4.5]
  55
  56* release notes for
  57  link:RelNotes-1.5.4.5.txt[1.5.4.5],
  58  link:RelNotes-1.5.4.4.txt[1.5.4.4],
  59  link:RelNotes-1.5.4.3.txt[1.5.4.3],
  60  link:RelNotes-1.5.4.2.txt[1.5.4.2],
  61  link:RelNotes-1.5.4.1.txt[1.5.4.1],
  62  link:RelNotes-1.5.4.txt[1.5.4].
  63
  64* link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
  65
  66* release notes for
  67  link:RelNotes-1.5.3.8.txt[1.5.3.8],
  68  link:RelNotes-1.5.3.7.txt[1.5.3.7],
  69  link:RelNotes-1.5.3.6.txt[1.5.3.6],
  70  link:RelNotes-1.5.3.5.txt[1.5.3.5],
  71  link:RelNotes-1.5.3.4.txt[1.5.3.4],
  72  link:RelNotes-1.5.3.3.txt[1.5.3.3],
  73  link:RelNotes-1.5.3.2.txt[1.5.3.2],
  74  link:RelNotes-1.5.3.1.txt[1.5.3.1],
  75  link:RelNotes-1.5.3.txt[1.5.3].
  76
  77* release notes for
  78  link:RelNotes-1.5.2.5.txt[1.5.2.5],
  79  link:RelNotes-1.5.2.4.txt[1.5.2.4],
  80  link:RelNotes-1.5.2.3.txt[1.5.2.3],
  81  link:RelNotes-1.5.2.2.txt[1.5.2.2],
  82  link:RelNotes-1.5.2.1.txt[1.5.2.1],
  83  link:RelNotes-1.5.2.txt[1.5.2].
  84
  85* link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
  86
  87* release notes for
  88  link:RelNotes-1.5.1.6.txt[1.5.1.6],
  89  link:RelNotes-1.5.1.5.txt[1.5.1.5],
  90  link:RelNotes-1.5.1.4.txt[1.5.1.4],
  91  link:RelNotes-1.5.1.3.txt[1.5.1.3],
  92  link:RelNotes-1.5.1.2.txt[1.5.1.2],
  93  link:RelNotes-1.5.1.1.txt[1.5.1.1],
  94  link:RelNotes-1.5.1.txt[1.5.1].
  95
  96* link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
  97
  98* release notes for
  99  link:RelNotes-1.5.0.7.txt[1.5.0.7],
 100  link:RelNotes-1.5.0.6.txt[1.5.0.6],
 101  link:RelNotes-1.5.0.5.txt[1.5.0.5],
 102  link:RelNotes-1.5.0.3.txt[1.5.0.3],
 103  link:RelNotes-1.5.0.2.txt[1.5.0.2],
 104  link:RelNotes-1.5.0.1.txt[1.5.0.1],
 105  link:RelNotes-1.5.0.txt[1.5.0].
 106
 107* documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 108  link:v1.3.3/git.html[1.3.3],
 109  link:v1.2.6/git.html[1.2.6],
 110  link:v1.0.13/git.html[1.0.13].
 111
 112============
 113
 114endif::stalenotes[]
 115
 116OPTIONS
 117-------
 118--version::
 119        Prints the git suite version that the 'git' program came from.
 120
 121--help::
 122        Prints the synopsis and a list of the most commonly used
 123        commands. If the option '--all' or '-a' is given then all
 124        available commands are printed. If a git command is named this
 125        option will bring up the manual page for that command.
 126+
 127Other options are available to control how the manual page is
 128displayed. See linkgit:git-help[1] for more information,
 129because 'git --help ...' is converted internally into 'git
 130help ...'.
 131
 132--exec-path::
 133        Path to wherever your core git programs are installed.
 134        This can also be controlled by setting the GIT_EXEC_PATH
 135        environment variable. If no path is given 'git' will print
 136        the current setting and then exit.
 137
 138-p|--paginate::
 139        Pipe all output into 'less' (or if set, $PAGER).
 140
 141--no-pager::
 142        Do not pipe git output into a pager.
 143
 144--git-dir=<path>::
 145        Set the path to the repository. This can also be controlled by
 146        setting the GIT_DIR environment variable.
 147
 148--work-tree=<path>::
 149        Set the path to the working tree.  The value will not be
 150        used in combination with repositories found automatically in
 151        a .git directory (i.e. $GIT_DIR is not set).
 152        This can also be controlled by setting the GIT_WORK_TREE
 153        environment variable and the core.worktree configuration
 154        variable.
 155
 156--bare::
 157        Treat the repository as a bare repository.  If GIT_DIR
 158        environment is not set, it is set to the current working
 159        directory.
 160
 161
 162FURTHER DOCUMENTATION
 163---------------------
 164
 165See the references above to get started using git.  The following is
 166probably more detail than necessary for a first-time user.
 167
 168The link:user-manual.html#git-concepts[git concepts chapter of the
 169user-manual] and the link:core-tutorial.html[Core tutorial] both provide
 170introductions to the underlying git architecture.
 171
 172See also the link:howto-index.html[howto] documents for some useful
 173examples.
 174
 175The internals are documented link:technical/api-index.html[here].
 176
 177GIT COMMANDS
 178------------
 179
 180We divide git into high level ("porcelain") commands and low level
 181("plumbing") commands.
 182
 183High-level commands (porcelain)
 184-------------------------------
 185
 186We separate the porcelain commands into the main commands and some
 187ancillary user utilities.
 188
 189Main porcelain commands
 190~~~~~~~~~~~~~~~~~~~~~~~
 191
 192include::cmds-mainporcelain.txt[]
 193
 194Ancillary Commands
 195~~~~~~~~~~~~~~~~~~
 196Manipulators:
 197
 198include::cmds-ancillarymanipulators.txt[]
 199
 200Interrogators:
 201
 202include::cmds-ancillaryinterrogators.txt[]
 203
 204
 205Interacting with Others
 206~~~~~~~~~~~~~~~~~~~~~~~
 207
 208These commands are to interact with foreign SCM and with other
 209people via patch over e-mail.
 210
 211include::cmds-foreignscminterface.txt[]
 212
 213
 214Low-level commands (plumbing)
 215-----------------------------
 216
 217Although git includes its
 218own porcelain layer, its low-level commands are sufficient to support
 219development of alternative porcelains.  Developers of such porcelains
 220might start by reading about linkgit:git-update-index[1] and
 221linkgit:git-read-tree[1].
 222
 223The interface (input, output, set of options and the semantics)
 224to these low-level commands are meant to be a lot more stable
 225than Porcelain level commands, because these commands are
 226primarily for scripted use.  The interface to Porcelain commands
 227on the other hand are subject to change in order to improve the
 228end user experience.
 229
 230The following description divides
 231the low-level commands into commands that manipulate objects (in
 232the repository, index, and working tree), commands that interrogate and
 233compare objects, and commands that move objects and references between
 234repositories.
 235
 236
 237Manipulation commands
 238~~~~~~~~~~~~~~~~~~~~~
 239
 240include::cmds-plumbingmanipulators.txt[]
 241
 242
 243Interrogation commands
 244~~~~~~~~~~~~~~~~~~~~~~
 245
 246include::cmds-plumbinginterrogators.txt[]
 247
 248In general, the interrogate commands do not touch the files in
 249the working tree.
 250
 251
 252Synching repositories
 253~~~~~~~~~~~~~~~~~~~~~
 254
 255include::cmds-synchingrepositories.txt[]
 256
 257The following are helper programs used by the above; end users
 258typically do not use them directly.
 259
 260include::cmds-synchelpers.txt[]
 261
 262
 263Internal helper commands
 264~~~~~~~~~~~~~~~~~~~~~~~~
 265
 266These are internal helper commands used by other commands; end
 267users typically do not use them directly.
 268
 269include::cmds-purehelpers.txt[]
 270
 271
 272Configuration Mechanism
 273-----------------------
 274
 275Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 276is used to hold per-repository configuration options.  It is a
 277simple text file modeled after `.ini` format familiar to some
 278people.  Here is an example:
 279
 280------------
 281#
 282# A '#' or ';' character indicates a comment.
 283#
 284
 285; core variables
 286[core]
 287        ; Don't trust file modes
 288        filemode = false
 289
 290; user identity
 291[user]
 292        name = "Junio C Hamano"
 293        email = "junkio@twinsun.com"
 294
 295------------
 296
 297Various commands read from the configuration file and adjust
 298their operation accordingly.
 299
 300
 301Identifier Terminology
 302----------------------
 303<object>::
 304        Indicates the object name for any type of object.
 305
 306<blob>::
 307        Indicates a blob object name.
 308
 309<tree>::
 310        Indicates a tree object name.
 311
 312<commit>::
 313        Indicates a commit object name.
 314
 315<tree-ish>::
 316        Indicates a tree, commit or tag object name.  A
 317        command that takes a <tree-ish> argument ultimately wants to
 318        operate on a <tree> object but automatically dereferences
 319        <commit> and <tag> objects that point at a <tree>.
 320
 321<commit-ish>::
 322        Indicates a commit or tag object name.  A
 323        command that takes a <commit-ish> argument ultimately wants to
 324        operate on a <commit> object but automatically dereferences
 325        <tag> objects that point at a <commit>.
 326
 327<type>::
 328        Indicates that an object type is required.
 329        Currently one of: `blob`, `tree`, `commit`, or `tag`.
 330
 331<file>::
 332        Indicates a filename - almost always relative to the
 333        root of the tree structure `GIT_INDEX_FILE` describes.
 334
 335Symbolic Identifiers
 336--------------------
 337Any git command accepting any <object> can also use the following
 338symbolic notation:
 339
 340HEAD::
 341        indicates the head of the current branch (i.e. the
 342        contents of `$GIT_DIR/HEAD`).
 343
 344<tag>::
 345        a valid tag 'name'
 346        (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`).
 347
 348<head>::
 349        a valid head 'name'
 350        (i.e. the contents of `$GIT_DIR/refs/heads/<head>`).
 351
 352For a more complete list of ways to spell object names, see
 353"SPECIFYING REVISIONS" section in linkgit:git-rev-parse[1].
 354
 355
 356File/Directory Structure
 357------------------------
 358
 359Please see the link:repository-layout.html[repository layout] document.
 360
 361Read link:hooks.html[hooks] for more details about each hook.
 362
 363Higher level SCMs may provide and manage additional information in the
 364`$GIT_DIR`.
 365
 366
 367Terminology
 368-----------
 369Please see the link:glossary.html[glossary] document.
 370
 371
 372Environment Variables
 373---------------------
 374Various git commands use the following environment variables:
 375
 376The git Repository
 377~~~~~~~~~~~~~~~~~~
 378These environment variables apply to 'all' core git commands. Nb: it
 379is worth noting that they may be used/overridden by SCMS sitting above
 380git so take care if using Cogito etc.
 381
 382'GIT_INDEX_FILE'::
 383        This environment allows the specification of an alternate
 384        index file. If not specified, the default of `$GIT_DIR/index`
 385        is used.
 386
 387'GIT_OBJECT_DIRECTORY'::
 388        If the object storage directory is specified via this
 389        environment variable then the sha1 directories are created
 390        underneath - otherwise the default `$GIT_DIR/objects`
 391        directory is used.
 392
 393'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 394        Due to the immutable nature of git objects, old objects can be
 395        archived into shared, read-only directories. This variable
 396        specifies a ":" separated list of git object directories which
 397        can be used to search for git objects. New objects will not be
 398        written to these directories.
 399
 400'GIT_DIR'::
 401        If the 'GIT_DIR' environment variable is set then it
 402        specifies a path to use instead of the default `.git`
 403        for the base of the repository.
 404
 405'GIT_WORK_TREE'::
 406        Set the path to the working tree.  The value will not be
 407        used in combination with repositories found automatically in
 408        a .git directory (i.e. $GIT_DIR is not set).
 409        This can also be controlled by the '--work-tree' command line
 410        option and the core.worktree configuration variable.
 411
 412git Commits
 413~~~~~~~~~~~
 414'GIT_AUTHOR_NAME'::
 415'GIT_AUTHOR_EMAIL'::
 416'GIT_AUTHOR_DATE'::
 417'GIT_COMMITTER_NAME'::
 418'GIT_COMMITTER_EMAIL'::
 419'GIT_COMMITTER_DATE'::
 420'EMAIL'::
 421        see linkgit:git-commit-tree[1]
 422
 423git Diffs
 424~~~~~~~~~
 425'GIT_DIFF_OPTS'::
 426        Only valid setting is "--unified=??" or "-u??" to set the
 427        number of context lines shown when a unified diff is created.
 428        This takes precedence over any "-U" or "--unified" option
 429        value passed on the git diff command line.
 430
 431'GIT_EXTERNAL_DIFF'::
 432        When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 433        program named by it is called, instead of the diff invocation
 434        described above.  For a path that is added, removed, or modified,
 435        'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 436
 437        path old-file old-hex old-mode new-file new-hex new-mode
 438+
 439where:
 440
 441        <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 442                         contents of <old|new>,
 443        <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 444        <old|new>-mode:: are the octal representation of the file modes.
 445
 446+
 447The file parameters can point at the user's working file
 448(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 449when a new file is added), or a temporary file (e.g. `old-file` in the
 450index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 451temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 452+
 453For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 454parameter, <path>.
 455
 456other
 457~~~~~
 458'GIT_MERGE_VERBOSITY'::
 459        A number controlling the amount of output shown by
 460        the recursive merge strategy.  Overrides merge.verbosity.
 461        See linkgit:git-merge[1]
 462
 463'GIT_PAGER'::
 464        This environment variable overrides `$PAGER`. If it is set
 465        to an empty string or to the value "cat", git will not launch
 466        a pager.
 467
 468'GIT_SSH'::
 469        If this environment variable is set then linkgit:git-fetch[1]
 470        and linkgit:git-push[1] will use this command instead
 471        of `ssh` when they need to connect to a remote system.
 472        The 'GIT_SSH' command will be given exactly two arguments:
 473        the 'username@host' (or just 'host') from the URL and the
 474        shell command to execute on that remote system.
 475+
 476To pass options to the program that you want to list in GIT_SSH
 477you will need to wrap the program and options into a shell script,
 478then set GIT_SSH to refer to the shell script.
 479+
 480Usually it is easier to configure any desired options through your
 481personal `.ssh/config` file.  Please consult your ssh documentation
 482for further details.
 483
 484'GIT_FLUSH'::
 485        If this environment variable is set to "1", then commands such
 486        as git-blame (in incremental mode), git-rev-list, git-log,
 487        git-whatchanged, etc., will force a flush of the output stream
 488        after each commit-oriented record have been flushed.   If this
 489        variable is set to "0", the output of these commands will be done
 490        using completely buffered I/O.   If this environment variable is
 491        not set, git will choose buffered or record-oriented flushing
 492        based on whether stdout appears to be redirected to a file or not.
 493
 494'GIT_TRACE'::
 495        If this variable is set to "1", "2" or "true" (comparison
 496        is case insensitive), git will print `trace:` messages on
 497        stderr telling about alias expansion, built-in command
 498        execution and external command execution.
 499        If this variable is set to an integer value greater than 1
 500        and lower than 10 (strictly) then git will interpret this
 501        value as an open file descriptor and will try to write the
 502        trace messages into this file descriptor.
 503        Alternatively, if this variable is set to an absolute path
 504        (starting with a '/' character), git will interpret this
 505        as a file path and will try to write the trace messages
 506        into it.
 507
 508Discussion[[Discussion]]
 509------------------------
 510
 511More detail on the following is available from the
 512link:user-manual.html#git-concepts[git concepts chapter of the
 513user-manual] and the link:core-tutorial.html[Core tutorial].
 514
 515A git project normally consists of a working directory with a ".git"
 516subdirectory at the top level.  The .git directory contains, among other
 517things, a compressed object database representing the complete history
 518of the project, an "index" file which links that history to the current
 519contents of the working tree, and named pointers into that history such
 520as tags and branch heads.
 521
 522The object database contains objects of three main types: blobs, which
 523hold file data; trees, which point to blobs and other trees to build up
 524directory hierarchies; and commits, which each reference a single tree
 525and some number of parent commits.
 526
 527The commit, equivalent to what other systems call a "changeset" or
 528"version", represents a step in the project's history, and each parent
 529represents an immediately preceding step.  Commits with more than one
 530parent represent merges of independent lines of development.
 531
 532All objects are named by the SHA1 hash of their contents, normally
 533written as a string of 40 hex digits.  Such names are globally unique.
 534The entire history leading up to a commit can be vouched for by signing
 535just that commit.  A fourth object type, the tag, is provided for this
 536purpose.
 537
 538When first created, objects are stored in individual files, but for
 539efficiency may later be compressed together into "pack files".
 540
 541Named pointers called refs mark interesting points in history.  A ref
 542may contain the SHA1 name of an object or the name of another ref.  Refs
 543with names beginning `ref/head/` contain the SHA1 name of the most
 544recent commit (or "head") of a branch under development.  SHA1 names of
 545tags of interest are stored under `ref/tags/`.  A special ref named
 546`HEAD` contains the name of the currently checked-out branch.
 547
 548The index file is initialized with a list of all paths and, for each
 549path, a blob object and a set of attributes.  The blob object represents
 550the contents of the file as of the head of the current branch.  The
 551attributes (last modified time, size, etc.) are taken from the
 552corresponding file in the working tree.  Subsequent changes to the
 553working tree can be found by comparing these attributes.  The index may
 554be updated with new content, and new commits may be created from the
 555content stored in the index.
 556
 557The index is also capable of storing multiple entries (called "stages")
 558for a given pathname.  These stages are used to hold the various
 559unmerged version of a file when a merge is in progress.
 560
 561Authors
 562-------
 563* git's founding father is Linus Torvalds <torvalds@osdl.org>.
 564* The current git nurse is Junio C Hamano <gitster@pobox.com>.
 565* The git potty was written by Andreas Ericsson <ae@op5.se>.
 566* General upbringing is handled by the git-list <git@vger.kernel.org>.
 567
 568Documentation
 569--------------
 570The documentation for git suite was started by David Greaves
 571<david@dgreaves.com>, and later enhanced greatly by the
 572contributors on the git-list <git@vger.kernel.org>.
 573
 574GIT
 575---
 576Part of the linkgit:git[7] suite