Documentation / git.txton commit diff.c: fix emit_line() again not to add extra line (4afbcab)
   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-1.5.5.4.txt[1.5.5.4],
  50  link:RelNotes-1.5.5.3.txt[1.5.5.3],
  51  link:RelNotes-1.5.5.2.txt[1.5.5.2],
  52  link:RelNotes-1.5.5.1.txt[1.5.5.1],
  53  link:RelNotes-1.5.5.txt[1.5.5].
  54
  55* link:v1.5.5.4/git.html[documentation for release 1.5.5.4]
  56
  57* link:v1.5.4.5/git.html[documentation for release 1.5.4.5]
  58
  59* release notes for
  60  link:RelNotes-1.5.4.5.txt[1.5.4.5],
  61  link:RelNotes-1.5.4.4.txt[1.5.4.4],
  62  link:RelNotes-1.5.4.3.txt[1.5.4.3],
  63  link:RelNotes-1.5.4.2.txt[1.5.4.2],
  64  link:RelNotes-1.5.4.1.txt[1.5.4.1],
  65  link:RelNotes-1.5.4.txt[1.5.4].
  66
  67* link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
  68
  69* release notes for
  70  link:RelNotes-1.5.3.8.txt[1.5.3.8],
  71  link:RelNotes-1.5.3.7.txt[1.5.3.7],
  72  link:RelNotes-1.5.3.6.txt[1.5.3.6],
  73  link:RelNotes-1.5.3.5.txt[1.5.3.5],
  74  link:RelNotes-1.5.3.4.txt[1.5.3.4],
  75  link:RelNotes-1.5.3.3.txt[1.5.3.3],
  76  link:RelNotes-1.5.3.2.txt[1.5.3.2],
  77  link:RelNotes-1.5.3.1.txt[1.5.3.1],
  78  link:RelNotes-1.5.3.txt[1.5.3].
  79
  80* release notes for
  81  link:RelNotes-1.5.2.5.txt[1.5.2.5],
  82  link:RelNotes-1.5.2.4.txt[1.5.2.4],
  83  link:RelNotes-1.5.2.3.txt[1.5.2.3],
  84  link:RelNotes-1.5.2.2.txt[1.5.2.2],
  85  link:RelNotes-1.5.2.1.txt[1.5.2.1],
  86  link:RelNotes-1.5.2.txt[1.5.2].
  87
  88* link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
  89
  90* release notes for
  91  link:RelNotes-1.5.1.6.txt[1.5.1.6],
  92  link:RelNotes-1.5.1.5.txt[1.5.1.5],
  93  link:RelNotes-1.5.1.4.txt[1.5.1.4],
  94  link:RelNotes-1.5.1.3.txt[1.5.1.3],
  95  link:RelNotes-1.5.1.2.txt[1.5.1.2],
  96  link:RelNotes-1.5.1.1.txt[1.5.1.1],
  97  link:RelNotes-1.5.1.txt[1.5.1].
  98
  99* link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
 100
 101* release notes for
 102  link:RelNotes-1.5.0.7.txt[1.5.0.7],
 103  link:RelNotes-1.5.0.6.txt[1.5.0.6],
 104  link:RelNotes-1.5.0.5.txt[1.5.0.5],
 105  link:RelNotes-1.5.0.3.txt[1.5.0.3],
 106  link:RelNotes-1.5.0.2.txt[1.5.0.2],
 107  link:RelNotes-1.5.0.1.txt[1.5.0.1],
 108  link:RelNotes-1.5.0.txt[1.5.0].
 109
 110* documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 111  link:v1.3.3/git.html[1.3.3],
 112  link:v1.2.6/git.html[1.2.6],
 113  link:v1.0.13/git.html[1.0.13].
 114
 115============
 116
 117endif::stalenotes[]
 118
 119OPTIONS
 120-------
 121--version::
 122        Prints the git suite version that the 'git' program came from.
 123
 124--help::
 125        Prints the synopsis and a list of the most commonly used
 126        commands. If the option '--all' or '-a' is given then all
 127        available commands are printed. If a git command is named this
 128        option will bring up the manual page for that command.
 129+
 130Other options are available to control how the manual page is
 131displayed. See linkgit:git-help[1] for more information,
 132because 'git --help ...' is converted internally into 'git
 133help ...'.
 134
 135--exec-path::
 136        Path to wherever your core git programs are installed.
 137        This can also be controlled by setting the GIT_EXEC_PATH
 138        environment variable. If no path is given 'git' will print
 139        the current setting and then exit.
 140
 141-p|--paginate::
 142        Pipe all output into 'less' (or if set, $PAGER).
 143
 144--no-pager::
 145        Do not pipe git output into a pager.
 146
 147--git-dir=<path>::
 148        Set the path to the repository. This can also be controlled by
 149        setting the GIT_DIR environment variable.
 150
 151--work-tree=<path>::
 152        Set the path to the working tree.  The value will not be
 153        used in combination with repositories found automatically in
 154        a .git directory (i.e. $GIT_DIR is not set).
 155        This can also be controlled by setting the GIT_WORK_TREE
 156        environment variable and the core.worktree configuration
 157        variable.
 158
 159--bare::
 160        Treat the repository as a bare repository.  If GIT_DIR
 161        environment is not set, it is set to the current working
 162        directory.
 163
 164
 165FURTHER DOCUMENTATION
 166---------------------
 167
 168See the references above to get started using git.  The following is
 169probably more detail than necessary for a first-time user.
 170
 171The link:user-manual.html#git-concepts[git concepts chapter of the
 172user-manual] and the link:core-tutorial.html[Core tutorial] both provide
 173introductions to the underlying git architecture.
 174
 175See also the link:howto-index.html[howto] documents for some useful
 176examples.
 177
 178The internals are documented link:technical/api-index.html[here].
 179
 180GIT COMMANDS
 181------------
 182
 183We divide git into high level ("porcelain") commands and low level
 184("plumbing") commands.
 185
 186High-level commands (porcelain)
 187-------------------------------
 188
 189We separate the porcelain commands into the main commands and some
 190ancillary user utilities.
 191
 192Main porcelain commands
 193~~~~~~~~~~~~~~~~~~~~~~~
 194
 195include::cmds-mainporcelain.txt[]
 196
 197Ancillary Commands
 198~~~~~~~~~~~~~~~~~~
 199Manipulators:
 200
 201include::cmds-ancillarymanipulators.txt[]
 202
 203Interrogators:
 204
 205include::cmds-ancillaryinterrogators.txt[]
 206
 207
 208Interacting with Others
 209~~~~~~~~~~~~~~~~~~~~~~~
 210
 211These commands are to interact with foreign SCM and with other
 212people via patch over e-mail.
 213
 214include::cmds-foreignscminterface.txt[]
 215
 216
 217Low-level commands (plumbing)
 218-----------------------------
 219
 220Although git includes its
 221own porcelain layer, its low-level commands are sufficient to support
 222development of alternative porcelains.  Developers of such porcelains
 223might start by reading about linkgit:git-update-index[1] and
 224linkgit:git-read-tree[1].
 225
 226The interface (input, output, set of options and the semantics)
 227to these low-level commands are meant to be a lot more stable
 228than Porcelain level commands, because these commands are
 229primarily for scripted use.  The interface to Porcelain commands
 230on the other hand are subject to change in order to improve the
 231end user experience.
 232
 233The following description divides
 234the low-level commands into commands that manipulate objects (in
 235the repository, index, and working tree), commands that interrogate and
 236compare objects, and commands that move objects and references between
 237repositories.
 238
 239
 240Manipulation commands
 241~~~~~~~~~~~~~~~~~~~~~
 242
 243include::cmds-plumbingmanipulators.txt[]
 244
 245
 246Interrogation commands
 247~~~~~~~~~~~~~~~~~~~~~~
 248
 249include::cmds-plumbinginterrogators.txt[]
 250
 251In general, the interrogate commands do not touch the files in
 252the working tree.
 253
 254
 255Synching repositories
 256~~~~~~~~~~~~~~~~~~~~~
 257
 258include::cmds-synchingrepositories.txt[]
 259
 260The following are helper programs used by the above; end users
 261typically do not use them directly.
 262
 263include::cmds-synchelpers.txt[]
 264
 265
 266Internal helper commands
 267~~~~~~~~~~~~~~~~~~~~~~~~
 268
 269These are internal helper commands used by other commands; end
 270users typically do not use them directly.
 271
 272include::cmds-purehelpers.txt[]
 273
 274
 275Configuration Mechanism
 276-----------------------
 277
 278Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 279is used to hold per-repository configuration options.  It is a
 280simple text file modeled after `.ini` format familiar to some
 281people.  Here is an example:
 282
 283------------
 284#
 285# A '#' or ';' character indicates a comment.
 286#
 287
 288; core variables
 289[core]
 290        ; Don't trust file modes
 291        filemode = false
 292
 293; user identity
 294[user]
 295        name = "Junio C Hamano"
 296        email = "junkio@twinsun.com"
 297
 298------------
 299
 300Various commands read from the configuration file and adjust
 301their operation accordingly.
 302
 303
 304Identifier Terminology
 305----------------------
 306<object>::
 307        Indicates the object name for any type of object.
 308
 309<blob>::
 310        Indicates a blob object name.
 311
 312<tree>::
 313        Indicates a tree object name.
 314
 315<commit>::
 316        Indicates a commit object name.
 317
 318<tree-ish>::
 319        Indicates a tree, commit or tag object name.  A
 320        command that takes a <tree-ish> argument ultimately wants to
 321        operate on a <tree> object but automatically dereferences
 322        <commit> and <tag> objects that point at a <tree>.
 323
 324<commit-ish>::
 325        Indicates a commit or tag object name.  A
 326        command that takes a <commit-ish> argument ultimately wants to
 327        operate on a <commit> object but automatically dereferences
 328        <tag> objects that point at a <commit>.
 329
 330<type>::
 331        Indicates that an object type is required.
 332        Currently one of: `blob`, `tree`, `commit`, or `tag`.
 333
 334<file>::
 335        Indicates a filename - almost always relative to the
 336        root of the tree structure `GIT_INDEX_FILE` describes.
 337
 338Symbolic Identifiers
 339--------------------
 340Any git command accepting any <object> can also use the following
 341symbolic notation:
 342
 343HEAD::
 344        indicates the head of the current branch (i.e. the
 345        contents of `$GIT_DIR/HEAD`).
 346
 347<tag>::
 348        a valid tag 'name'
 349        (i.e. the contents of `$GIT_DIR/refs/tags/<tag>`).
 350
 351<head>::
 352        a valid head 'name'
 353        (i.e. the contents of `$GIT_DIR/refs/heads/<head>`).
 354
 355For a more complete list of ways to spell object names, see
 356"SPECIFYING REVISIONS" section in linkgit:git-rev-parse[1].
 357
 358
 359File/Directory Structure
 360------------------------
 361
 362Please see the link:repository-layout.html[repository layout] document.
 363
 364Read link:hooks.html[hooks] for more details about each hook.
 365
 366Higher level SCMs may provide and manage additional information in the
 367`$GIT_DIR`.
 368
 369
 370Terminology
 371-----------
 372Please see the link:glossary.html[glossary] document.
 373
 374
 375Environment Variables
 376---------------------
 377Various git commands use the following environment variables:
 378
 379The git Repository
 380~~~~~~~~~~~~~~~~~~
 381These environment variables apply to 'all' core git commands. Nb: it
 382is worth noting that they may be used/overridden by SCMS sitting above
 383git so take care if using Cogito etc.
 384
 385'GIT_INDEX_FILE'::
 386        This environment allows the specification of an alternate
 387        index file. If not specified, the default of `$GIT_DIR/index`
 388        is used.
 389
 390'GIT_OBJECT_DIRECTORY'::
 391        If the object storage directory is specified via this
 392        environment variable then the sha1 directories are created
 393        underneath - otherwise the default `$GIT_DIR/objects`
 394        directory is used.
 395
 396'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 397        Due to the immutable nature of git objects, old objects can be
 398        archived into shared, read-only directories. This variable
 399        specifies a ":" separated list of git object directories which
 400        can be used to search for git objects. New objects will not be
 401        written to these directories.
 402
 403'GIT_DIR'::
 404        If the 'GIT_DIR' environment variable is set then it
 405        specifies a path to use instead of the default `.git`
 406        for the base of the repository.
 407
 408'GIT_WORK_TREE'::
 409        Set the path to the working tree.  The value will not be
 410        used in combination with repositories found automatically in
 411        a .git directory (i.e. $GIT_DIR is not set).
 412        This can also be controlled by the '--work-tree' command line
 413        option and the core.worktree configuration variable.
 414
 415git Commits
 416~~~~~~~~~~~
 417'GIT_AUTHOR_NAME'::
 418'GIT_AUTHOR_EMAIL'::
 419'GIT_AUTHOR_DATE'::
 420'GIT_COMMITTER_NAME'::
 421'GIT_COMMITTER_EMAIL'::
 422'GIT_COMMITTER_DATE'::
 423'EMAIL'::
 424        see linkgit:git-commit-tree[1]
 425
 426git Diffs
 427~~~~~~~~~
 428'GIT_DIFF_OPTS'::
 429        Only valid setting is "--unified=??" or "-u??" to set the
 430        number of context lines shown when a unified diff is created.
 431        This takes precedence over any "-U" or "--unified" option
 432        value passed on the git diff command line.
 433
 434'GIT_EXTERNAL_DIFF'::
 435        When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 436        program named by it is called, instead of the diff invocation
 437        described above.  For a path that is added, removed, or modified,
 438        'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 439
 440        path old-file old-hex old-mode new-file new-hex new-mode
 441+
 442where:
 443
 444        <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 445                         contents of <old|new>,
 446        <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 447        <old|new>-mode:: are the octal representation of the file modes.
 448
 449+
 450The file parameters can point at the user's working file
 451(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 452when a new file is added), or a temporary file (e.g. `old-file` in the
 453index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 454temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 455+
 456For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 457parameter, <path>.
 458
 459other
 460~~~~~
 461'GIT_MERGE_VERBOSITY'::
 462        A number controlling the amount of output shown by
 463        the recursive merge strategy.  Overrides merge.verbosity.
 464        See linkgit:git-merge[1]
 465
 466'GIT_PAGER'::
 467        This environment variable overrides `$PAGER`. If it is set
 468        to an empty string or to the value "cat", git will not launch
 469        a pager.
 470
 471'GIT_SSH'::
 472        If this environment variable is set then linkgit:git-fetch[1]
 473        and linkgit:git-push[1] will use this command instead
 474        of `ssh` when they need to connect to a remote system.
 475        The 'GIT_SSH' command will be given exactly two arguments:
 476        the 'username@host' (or just 'host') from the URL and the
 477        shell command to execute on that remote system.
 478+
 479To pass options to the program that you want to list in GIT_SSH
 480you will need to wrap the program and options into a shell script,
 481then set GIT_SSH to refer to the shell script.
 482+
 483Usually it is easier to configure any desired options through your
 484personal `.ssh/config` file.  Please consult your ssh documentation
 485for further details.
 486
 487'GIT_FLUSH'::
 488        If this environment variable is set to "1", then commands such
 489        as git-blame (in incremental mode), git-rev-list, git-log,
 490        git-whatchanged, etc., will force a flush of the output stream
 491        after each commit-oriented record have been flushed.   If this
 492        variable is set to "0", the output of these commands will be done
 493        using completely buffered I/O.   If this environment variable is
 494        not set, git will choose buffered or record-oriented flushing
 495        based on whether stdout appears to be redirected to a file or not.
 496
 497'GIT_TRACE'::
 498        If this variable is set to "1", "2" or "true" (comparison
 499        is case insensitive), git will print `trace:` messages on
 500        stderr telling about alias expansion, built-in command
 501        execution and external command execution.
 502        If this variable is set to an integer value greater than 1
 503        and lower than 10 (strictly) then git will interpret this
 504        value as an open file descriptor and will try to write the
 505        trace messages into this file descriptor.
 506        Alternatively, if this variable is set to an absolute path
 507        (starting with a '/' character), git will interpret this
 508        as a file path and will try to write the trace messages
 509        into it.
 510
 511Discussion[[Discussion]]
 512------------------------
 513
 514More detail on the following is available from the
 515link:user-manual.html#git-concepts[git concepts chapter of the
 516user-manual] and the link:core-tutorial.html[Core tutorial].
 517
 518A git project normally consists of a working directory with a ".git"
 519subdirectory at the top level.  The .git directory contains, among other
 520things, a compressed object database representing the complete history
 521of the project, an "index" file which links that history to the current
 522contents of the working tree, and named pointers into that history such
 523as tags and branch heads.
 524
 525The object database contains objects of three main types: blobs, which
 526hold file data; trees, which point to blobs and other trees to build up
 527directory hierarchies; and commits, which each reference a single tree
 528and some number of parent commits.
 529
 530The commit, equivalent to what other systems call a "changeset" or
 531"version", represents a step in the project's history, and each parent
 532represents an immediately preceding step.  Commits with more than one
 533parent represent merges of independent lines of development.
 534
 535All objects are named by the SHA1 hash of their contents, normally
 536written as a string of 40 hex digits.  Such names are globally unique.
 537The entire history leading up to a commit can be vouched for by signing
 538just that commit.  A fourth object type, the tag, is provided for this
 539purpose.
 540
 541When first created, objects are stored in individual files, but for
 542efficiency may later be compressed together into "pack files".
 543
 544Named pointers called refs mark interesting points in history.  A ref
 545may contain the SHA1 name of an object or the name of another ref.  Refs
 546with names beginning `ref/head/` contain the SHA1 name of the most
 547recent commit (or "head") of a branch under development.  SHA1 names of
 548tags of interest are stored under `ref/tags/`.  A special ref named
 549`HEAD` contains the name of the currently checked-out branch.
 550
 551The index file is initialized with a list of all paths and, for each
 552path, a blob object and a set of attributes.  The blob object represents
 553the contents of the file as of the head of the current branch.  The
 554attributes (last modified time, size, etc.) are taken from the
 555corresponding file in the working tree.  Subsequent changes to the
 556working tree can be found by comparing these attributes.  The index may
 557be updated with new content, and new commits may be created from the
 558content stored in the index.
 559
 560The index is also capable of storing multiple entries (called "stages")
 561for a given pathname.  These stages are used to hold the various
 562unmerged version of a file when a merge is in progress.
 563
 564Authors
 565-------
 566* git's founding father is Linus Torvalds <torvalds@osdl.org>.
 567* The current git nurse is Junio C Hamano <gitster@pobox.com>.
 568* The git potty was written by Andreas Ericsson <ae@op5.se>.
 569* General upbringing is handled by the git-list <git@vger.kernel.org>.
 570
 571Documentation
 572--------------
 573The documentation for git suite was started by David Greaves
 574<david@dgreaves.com>, and later enhanced greatly by the
 575contributors on the git-list <git@vger.kernel.org>.
 576
 577GIT
 578---
 579Part of the linkgit:git[7] suite