| 1 | [[def_alternate_object_database]]alternate object database:: |
| 2 | Via the alternates mechanism, a <<def_repository,repository>> |
| 3 | can inherit part of its <<def_object_database,object database>> |
| 4 | from another object database, which is called an "alternate". |
| 5 | |
| 6 | [[def_bare_repository]]bare repository:: |
| 7 | A bare repository is normally an appropriately |
| 8 | named <<def_directory,directory>> with a `.git` suffix that does not |
| 9 | have a locally checked-out copy of any of the files under |
| 10 | revision control. That is, all of the Git |
| 11 | administrative and control files that would normally be present in the |
| 12 | hidden `.git` sub-directory are directly present in the |
| 13 | `repository.git` directory instead, |
| 14 | and no other files are present and checked out. Usually publishers of |
| 15 | public repositories make bare repositories available. |
| 16 | |
| 17 | [[def_blob_object]]blob object:: |
| 18 | Untyped <<def_object,object>>, e.g. the contents of a file. |
| 19 | |
| 20 | [[def_branch]]branch:: |
| 21 | A "branch" is a line of development. The most recent |
| 22 | <<def_commit,commit>> on a branch is referred to as the tip of |
| 23 | that branch. The tip of the branch is <<def_ref,referenced>> by a branch |
| 24 | <<def_head,head>>, which moves forward as additional development |
| 25 | is done on the branch. A single Git |
| 26 | <<def_repository,repository>> can track an arbitrary number of |
| 27 | branches, but your <<def_working_tree,working tree>> is |
| 28 | associated with just one of them (the "current" or "checked out" |
| 29 | branch), and <<def_HEAD,HEAD>> points to that branch. |
| 30 | |
| 31 | [[def_cache]]cache:: |
| 32 | Obsolete for: <<def_index,index>>. |
| 33 | |
| 34 | [[def_chain]]chain:: |
| 35 | A list of objects, where each <<def_object,object>> in the list contains |
| 36 | a reference to its successor (for example, the successor of a |
| 37 | <<def_commit,commit>> could be one of its <<def_parent,parents>>). |
| 38 | |
| 39 | [[def_changeset]]changeset:: |
| 40 | BitKeeper/cvsps speak for "<<def_commit,commit>>". Since Git does not |
| 41 | store changes, but states, it really does not make sense to use the term |
| 42 | "changesets" with Git. |
| 43 | |
| 44 | [[def_checkout]]checkout:: |
| 45 | The action of updating all or part of the |
| 46 | <<def_working_tree,working tree>> with a <<def_tree_object,tree object>> |
| 47 | or <<def_blob_object,blob>> from the |
| 48 | <<def_object_database,object database>>, and updating the |
| 49 | <<def_index,index>> and <<def_HEAD,HEAD>> if the whole working tree has |
| 50 | been pointed at a new <<def_branch,branch>>. |
| 51 | |
| 52 | [[def_cherry-picking]]cherry-picking:: |
| 53 | In <<def_SCM,SCM>> jargon, "cherry pick" means to choose a subset of |
| 54 | changes out of a series of changes (typically commits) and record them |
| 55 | as a new series of changes on top of a different codebase. In Git, this is |
| 56 | performed by the "git cherry-pick" command to extract the change introduced |
| 57 | by an existing <<def_commit,commit>> and to record it based on the tip |
| 58 | of the current <<def_branch,branch>> as a new commit. |
| 59 | |
| 60 | [[def_clean]]clean:: |
| 61 | A <<def_working_tree,working tree>> is clean, if it |
| 62 | corresponds to the <<def_revision,revision>> referenced by the current |
| 63 | <<def_head,head>>. Also see "<<def_dirty,dirty>>". |
| 64 | |
| 65 | [[def_commit]]commit:: |
| 66 | As a noun: A single point in the |
| 67 | Git history; the entire history of a project is represented as a |
| 68 | set of interrelated commits. The word "commit" is often |
| 69 | used by Git in the same places other revision control systems |
| 70 | use the words "revision" or "version". Also used as a short |
| 71 | hand for <<def_commit_object,commit object>>. |
| 72 | + |
| 73 | As a verb: The action of storing a new snapshot of the project's |
| 74 | state in the Git history, by creating a new commit representing the current |
| 75 | state of the <<def_index,index>> and advancing <<def_HEAD,HEAD>> |
| 76 | to point at the new commit. |
| 77 | |
| 78 | [[def_commit_graph_general]]commit graph concept, representations and usage:: |
| 79 | A synonym for the <<def_DAG,DAG>> structure formed by the commits |
| 80 | in the object database, <<def_ref,referenced>> by branch tips, |
| 81 | using their <<def_chain,chain>> of linked commits. |
| 82 | This structure is the definitive commit graph. The |
| 83 | graph can be represented in other ways, e.g. the |
| 84 | <<def_commit_graph_file,"commit-graph" file>>. |
| 85 | |
| 86 | [[def_commit_graph_file]]commit-graph file:: |
| 87 | The "commit-graph" (normally hyphenated) file is a supplemental |
| 88 | representation of the <<def_commit_graph_general,commit graph>> |
| 89 | which accelerates commit graph walks. The "commit-graph" file is |
| 90 | stored either in the .git/objects/info directory or in the info |
| 91 | directory of an alternate object database. |
| 92 | |
| 93 | [[def_commit_object]]commit object:: |
| 94 | An <<def_object,object>> which contains the information about a |
| 95 | particular <<def_revision,revision>>, such as <<def_parent,parents>>, committer, |
| 96 | author, date and the <<def_tree_object,tree object>> which corresponds |
| 97 | to the top <<def_directory,directory>> of the stored |
| 98 | revision. |
| 99 | |
| 100 | [[def_commit-ish]]commit-ish (also committish):: |
| 101 | A <<def_commit_object,commit object>> or an <<def_object,object>> that |
| 102 | can be recursively <<def_dereference,dereferenced>> to a commit object. |
| 103 | The following are all commit-ishes: |
| 104 | a commit object, |
| 105 | a <<def_tag_object,tag object>> that points to a commit |
| 106 | object, |
| 107 | a tag object that points to a tag object that points to a |
| 108 | commit object, |
| 109 | etc. |
| 110 | |
| 111 | [[def_core_git]]core Git:: |
| 112 | Fundamental data structures and utilities of Git. Exposes only limited |
| 113 | source code management tools. |
| 114 | |
| 115 | [[def_DAG]]DAG:: |
| 116 | Directed acyclic graph. The <<def_commit_object,commit objects>> form a |
| 117 | directed acyclic graph, because they have parents (directed), and the |
| 118 | graph of commit objects is acyclic (there is no <<def_chain,chain>> |
| 119 | which begins and ends with the same <<def_object,object>>). |
| 120 | |
| 121 | [[def_dangling_object]]dangling object:: |
| 122 | An <<def_unreachable_object,unreachable object>> which is not |
| 123 | <<def_reachable,reachable>> even from other unreachable objects; a |
| 124 | dangling object has no references to it from any |
| 125 | reference or <<def_object,object>> in the <<def_repository,repository>>. |
| 126 | |
| 127 | [[def_dereference]]dereference:: |
| 128 | Referring to a <<def_symref,symbolic ref>>: the action of accessing the |
| 129 | <<def_ref,reference>> pointed at by a symbolic ref. Recursive |
| 130 | dereferencing involves repeating the aforementioned process on the |
| 131 | resulting ref until a non-symbolic reference is found. |
| 132 | + |
| 133 | Referring to a <<def_tag_object,tag object>>: the action of accessing the |
| 134 | <<def_object,object>> a tag points at. Tags are recursively dereferenced by |
| 135 | repeating the operation on the result object until the result has either a |
| 136 | specified <<def_object_type,object type>> (where applicable) or any non-"tag" |
| 137 | object type. A synonym for "recursive dereference" in the context of tags is |
| 138 | "<<def_peel,peel>>". |
| 139 | + |
| 140 | Referring to a <<def_commit_object,commit object>>: the action of accessing |
| 141 | the commit's tree object. Commits cannot be dereferenced recursively. |
| 142 | + |
| 143 | Unless otherwise specified, "dereferencing" as it used in the context of Git |
| 144 | commands or protocols is implicitly recursive. |
| 145 | |
| 146 | [[def_detached_HEAD]]detached HEAD:: |
| 147 | Normally the <<def_HEAD,HEAD>> stores the name of a |
| 148 | <<def_branch,branch>>, and commands that operate on the |
| 149 | history HEAD represents operate on the history leading to the |
| 150 | tip of the branch the HEAD points at. However, Git also |
| 151 | allows you to <<def_checkout,check out>> an arbitrary |
| 152 | <<def_commit,commit>> that isn't necessarily the tip of any |
| 153 | particular branch. The HEAD in such a state is called |
| 154 | "detached". |
| 155 | + |
| 156 | Note that commands that operate on the history of the current branch |
| 157 | (e.g. `git commit` to build a new history on top of it) still work |
| 158 | while the HEAD is detached. They update the HEAD to point at the tip |
| 159 | of the updated history without affecting any branch. Commands that |
| 160 | update or inquire information _about_ the current branch (e.g. `git |
| 161 | branch --set-upstream-to` that sets what remote-tracking branch the |
| 162 | current branch integrates with) obviously do not work, as there is no |
| 163 | (real) current branch to ask about in this state. |
| 164 | |
| 165 | [[def_directory]]directory:: |
| 166 | The list you get with "ls" :-) |
| 167 | |
| 168 | [[def_dirty]]dirty:: |
| 169 | A <<def_working_tree,working tree>> is said to be "dirty" if |
| 170 | it contains modifications which have not been <<def_commit,committed>> to the current |
| 171 | <<def_branch,branch>>. |
| 172 | |
| 173 | [[def_evil_merge]]evil merge:: |
| 174 | An evil merge is a <<def_merge,merge>> that introduces changes that |
| 175 | do not appear in any <<def_parent,parent>>. |
| 176 | |
| 177 | [[def_fast_forward]]fast-forward:: |
| 178 | A fast-forward is a special type of <<def_merge,merge>> where you have a |
| 179 | <<def_revision,revision>> and you are "merging" another |
| 180 | <<def_branch,branch>>'s changes that happen to be a descendant of what |
| 181 | you have. In such a case, you do not make a new <<def_merge,merge>> |
| 182 | <<def_commit,commit>> but instead just update your branch to point at the same |
| 183 | revision as the branch you are merging. This will happen frequently on a |
| 184 | <<def_remote_tracking_branch,remote-tracking branch>> of a remote |
| 185 | <<def_repository,repository>>. |
| 186 | |
| 187 | [[def_fetch]]fetch:: |
| 188 | Fetching a <<def_branch,branch>> means to get the |
| 189 | branch's <<def_head_ref,head ref>> from a remote |
| 190 | <<def_repository,repository>>, to find out which objects are |
| 191 | missing from the local <<def_object_database,object database>>, |
| 192 | and to get them, too. See also linkgit:git-fetch[1]. |
| 193 | |
| 194 | [[def_file_system]]file system:: |
| 195 | Linus Torvalds originally designed Git to be a user space file system, |
| 196 | i.e. the infrastructure to hold files and directories. That ensured the |
| 197 | efficiency and speed of Git. |
| 198 | |
| 199 | [[def_git_archive]]Git archive:: |
| 200 | Synonym for <<def_repository,repository>> (for arch people). |
| 201 | |
| 202 | [[def_gitfile]]gitfile:: |
| 203 | A plain file `.git` at the root of a working tree that |
| 204 | points at the directory that is the real repository. |
| 205 | For proper use see linkgit:git-worktree[1] or linkgit:git-submodule[1]. |
| 206 | For syntax see linkgit:gitrepository-layout[5]. |
| 207 | |
| 208 | [[def_grafts]]grafts:: |
| 209 | Grafts enable two otherwise different lines of development to be joined |
| 210 | together by recording fake ancestry information for commits. This way |
| 211 | you can make Git pretend the set of <<def_parent,parents>> a <<def_commit,commit>> has |
| 212 | is different from what was recorded when the commit was |
| 213 | created. Configured via the `.git/info/grafts` file. |
| 214 | + |
| 215 | Note that the grafts mechanism is outdated and can lead to problems |
| 216 | transferring objects between repositories; see linkgit:git-replace[1] |
| 217 | for a more flexible and robust system to do the same thing. |
| 218 | |
| 219 | [[def_hash]]hash:: |
| 220 | In Git's context, synonym for <<def_object_name,object name>>. |
| 221 | |
| 222 | [[def_head]]head:: |
| 223 | A <<def_ref,named reference>> to the <<def_commit,commit>> at the tip of a |
| 224 | <<def_branch,branch>>. Heads are stored in a file in |
| 225 | `$GIT_DIR/refs/heads/` directory, except when using packed refs. (See |
| 226 | linkgit:git-pack-refs[1].) |
| 227 | |
| 228 | [[def_HEAD]]HEAD:: |
| 229 | The current <<def_branch,branch>>. In more detail: Your <<def_working_tree, |
| 230 | working tree>> is normally derived from the state of the tree |
| 231 | referred to by HEAD. HEAD is a reference to one of the |
| 232 | <<def_head,heads>> in your repository, except when using a |
| 233 | <<def_detached_HEAD,detached HEAD>>, in which case it directly |
| 234 | references an arbitrary commit. |
| 235 | |
| 236 | [[def_head_ref]]head ref:: |
| 237 | A synonym for <<def_head,head>>. |
| 238 | |
| 239 | [[def_hook]]hook:: |
| 240 | During the normal execution of several Git commands, call-outs are made |
| 241 | to optional scripts that allow a developer to add functionality or |
| 242 | checking. Typically, the hooks allow for a command to be pre-verified |
| 243 | and potentially aborted, and allow for a post-notification after the |
| 244 | operation is done. The hook scripts are found in the |
| 245 | `$GIT_DIR/hooks/` directory, and are enabled by simply |
| 246 | removing the `.sample` suffix from the filename. In earlier versions |
| 247 | of Git you had to make them executable. |
| 248 | |
| 249 | [[def_index]]index:: |
| 250 | A collection of files with stat information, whose contents are stored |
| 251 | as objects. The index is a stored version of your |
| 252 | <<def_working_tree,working tree>>. Truth be told, it can also contain a second, and even |
| 253 | a third version of a working tree, which are used |
| 254 | when <<def_merge,merging>>. |
| 255 | |
| 256 | [[def_index_entry]]index entry:: |
| 257 | The information regarding a particular file, stored in the |
| 258 | <<def_index,index>>. An index entry can be unmerged, if a |
| 259 | <<def_merge,merge>> was started, but not yet finished (i.e. if |
| 260 | the index contains multiple versions of that file). |
| 261 | |
| 262 | [[def_master]]master:: |
| 263 | The default development <<def_branch,branch>>. Whenever you |
| 264 | create a Git <<def_repository,repository>>, a branch named |
| 265 | "master" is created, and becomes the active branch. In most |
| 266 | cases, this contains the local development, though that is |
| 267 | purely by convention and is not required. |
| 268 | |
| 269 | [[def_merge]]merge:: |
| 270 | As a verb: To bring the contents of another |
| 271 | <<def_branch,branch>> (possibly from an external |
| 272 | <<def_repository,repository>>) into the current branch. In the |
| 273 | case where the merged-in branch is from a different repository, |
| 274 | this is done by first <<def_fetch,fetching>> the remote branch |
| 275 | and then merging the result into the current branch. This |
| 276 | combination of fetch and merge operations is called a |
| 277 | <<def_pull,pull>>. Merging is performed by an automatic process |
| 278 | that identifies changes made since the branches diverged, and |
| 279 | then applies all those changes together. In cases where changes |
| 280 | conflict, manual intervention may be required to complete the |
| 281 | merge. |
| 282 | + |
| 283 | As a noun: unless it is a <<def_fast_forward,fast-forward>>, a |
| 284 | successful merge results in the creation of a new <<def_commit,commit>> |
| 285 | representing the result of the merge, and having as |
| 286 | <<def_parent,parents>> the tips of the merged <<def_branch,branches>>. |
| 287 | This commit is referred to as a "merge commit", or sometimes just a |
| 288 | "merge". |
| 289 | |
| 290 | [[def_object]]object:: |
| 291 | The unit of storage in Git. It is uniquely identified by the |
| 292 | <<def_SHA1,SHA-1>> of its contents. Consequently, an |
| 293 | object cannot be changed. |
| 294 | |
| 295 | [[def_object_database]]object database:: |
| 296 | Stores a set of "objects", and an individual <<def_object,object>> is |
| 297 | identified by its <<def_object_name,object name>>. The objects usually |
| 298 | live in `$GIT_DIR/objects/`. |
| 299 | |
| 300 | [[def_object_identifier]]object identifier, object ID, oid:: |
| 301 | Synonyms for <<def_object_name,object name>>. |
| 302 | |
| 303 | [[def_object_name]]object name:: |
| 304 | The unique identifier of an <<def_object,object>>. The |
| 305 | object name is usually represented by a 40 character |
| 306 | hexadecimal string. Also colloquially called <<def_SHA1,SHA-1>>. |
| 307 | |
| 308 | [[def_object_type]]object type:: |
| 309 | One of the identifiers "<<def_commit_object,commit>>", |
| 310 | "<<def_tree_object,tree>>", "<<def_tag_object,tag>>" or |
| 311 | "<<def_blob_object,blob>>" describing the type of an |
| 312 | <<def_object,object>>. |
| 313 | |
| 314 | [[def_octopus]]octopus:: |
| 315 | To <<def_merge,merge>> more than two <<def_branch,branches>>. |
| 316 | |
| 317 | [[def_orphan]]orphan:: |
| 318 | The act of getting on a <<def_branch,branch>> that does not |
| 319 | exist yet (i.e., an <<def_unborn,unborn>> branch). After |
| 320 | such an operation, the commit first created becomes a commit |
| 321 | without a parent, starting a new history. |
| 322 | |
| 323 | [[def_origin]]origin:: |
| 324 | The default upstream <<def_repository,repository>>. Most projects have |
| 325 | at least one upstream project which they track. By default |
| 326 | 'origin' is used for that purpose. New upstream updates |
| 327 | will be fetched into <<def_remote_tracking_branch,remote-tracking branches>> named |
| 328 | origin/name-of-upstream-branch, which you can see using |
| 329 | `git branch -r`. |
| 330 | |
| 331 | [[def_overlay]]overlay:: |
| 332 | Only update and add files to the working directory, but don't |
| 333 | delete them, similar to how 'cp -R' would update the contents |
| 334 | in the destination directory. This is the default mode in a |
| 335 | <<def_checkout,checkout>> when checking out files from the |
| 336 | <<def_index,index>> or a <<def_tree-ish,tree-ish>>. In |
| 337 | contrast, no-overlay mode also deletes tracked files not |
| 338 | present in the source, similar to 'rsync --delete'. |
| 339 | |
| 340 | [[def_pack]]pack:: |
| 341 | A set of objects which have been compressed into one file (to save space |
| 342 | or to transmit them efficiently). |
| 343 | |
| 344 | [[def_pack_index]]pack index:: |
| 345 | The list of identifiers, and other information, of the objects in a |
| 346 | <<def_pack,pack>>, to assist in efficiently accessing the contents of a |
| 347 | pack. |
| 348 | |
| 349 | [[def_pathspec]]pathspec:: |
| 350 | Pattern used to limit paths in Git commands. |
| 351 | + |
| 352 | Pathspecs are used on the command line of "git ls-files", "git |
| 353 | ls-tree", "git add", "git grep", "git diff", "git checkout", |
| 354 | and many other commands to |
| 355 | limit the scope of operations to some subset of the tree or |
| 356 | working tree. See the documentation of each command for whether |
| 357 | paths are relative to the current directory or toplevel. The |
| 358 | pathspec syntax is as follows: |
| 359 | + |
| 360 | -- |
| 361 | |
| 362 | * any path matches itself |
| 363 | * the pathspec up to the last slash represents a |
| 364 | directory prefix. The scope of that pathspec is |
| 365 | limited to that subtree. |
| 366 | * the rest of the pathspec is a pattern for the remainder |
| 367 | of the pathname. Paths relative to the directory |
| 368 | prefix will be matched against that pattern using fnmatch(3); |
| 369 | in particular, '*' and '?' _can_ match directory separators. |
| 370 | |
| 371 | -- |
| 372 | + |
| 373 | For example, Documentation/*.jpg will match all .jpg files |
| 374 | in the Documentation subtree, |
| 375 | including Documentation/chapter_1/figure_1.jpg. |
| 376 | + |
| 377 | A pathspec that begins with a colon `:` has special meaning. In the |
| 378 | short form, the leading colon `:` is followed by zero or more "magic |
| 379 | signature" letters (which optionally is terminated by another colon `:`), |
| 380 | and the remainder is the pattern to match against the path. |
| 381 | The "magic signature" consists of ASCII symbols that are neither |
| 382 | alphanumeric, glob, regex special characters nor colon. |
| 383 | The optional colon that terminates the "magic signature" can be |
| 384 | omitted if the pattern begins with a character that does not belong to |
| 385 | "magic signature" symbol set and is not a colon. |
| 386 | + |
| 387 | In the long form, the leading colon `:` is followed by an open |
| 388 | parenthesis `(`, a comma-separated list of zero or more "magic words", |
| 389 | and a close parentheses `)`, and the remainder is the pattern to match |
| 390 | against the path. |
| 391 | + |
| 392 | A pathspec with only a colon means "there is no pathspec". This form |
| 393 | should not be combined with other pathspec. |
| 394 | + |
| 395 | -- |
| 396 | top;; |
| 397 | The magic word `top` (magic signature: `/`) makes the pattern |
| 398 | match from the root of the working tree, even when you are |
| 399 | running the command from inside a subdirectory. |
| 400 | |
| 401 | literal;; |
| 402 | Wildcards in the pattern such as `*` or `?` are treated |
| 403 | as literal characters. |
| 404 | |
| 405 | icase;; |
| 406 | Case insensitive match. |
| 407 | |
| 408 | glob;; |
| 409 | Git treats the pattern as a shell glob suitable for |
| 410 | consumption by fnmatch(3) with the FNM_PATHNAME flag: |
| 411 | wildcards in the pattern will not match a / in the pathname. |
| 412 | For example, "Documentation/{asterisk}.html" matches |
| 413 | "Documentation/git.html" but not "Documentation/ppc/ppc.html" |
| 414 | or "tools/perf/Documentation/perf.html". |
| 415 | + |
| 416 | Two consecutive asterisks ("`**`") in patterns matched against |
| 417 | full pathname may have special meaning: |
| 418 | |
| 419 | - A leading "`**`" followed by a slash means match in all |
| 420 | directories. For example, "`**/foo`" matches file or directory |
| 421 | "`foo`" anywhere. "`**/foo/bar`" matches file or directory "`bar`" |
| 422 | anywhere that is directly under directory "`foo`". |
| 423 | |
| 424 | - A trailing "`/**`" matches everything inside. For example, |
| 425 | "`abc/**`" matches all files inside directory "abc", relative |
| 426 | to the location of the `.gitignore` file, with infinite depth. |
| 427 | |
| 428 | - A slash followed by two consecutive asterisks then a slash |
| 429 | matches zero or more directories. For example, "`a/**/b`" |
| 430 | matches "`a/b`", "`a/x/b`", "`a/x/y/b`" and so on. |
| 431 | |
| 432 | - Other consecutive asterisks are considered invalid. |
| 433 | |
| 434 | + |
| 435 | Glob magic is incompatible with literal magic. |
| 436 | |
| 437 | attr;; |
| 438 | After `attr:` comes a space separated list of "attribute |
| 439 | requirements", all of which must be met in order for the |
| 440 | path to be considered a match; this is in addition to the |
| 441 | usual non-magic pathspec pattern matching. |
| 442 | See linkgit:gitattributes[5]. |
| 443 | + |
| 444 | Each of the attribute requirements for the path takes one of |
| 445 | these forms: |
| 446 | |
| 447 | - "`ATTR`" requires that the attribute `ATTR` be set. |
| 448 | |
| 449 | - "`-ATTR`" requires that the attribute `ATTR` be unset. |
| 450 | |
| 451 | - "`ATTR=VALUE`" requires that the attribute `ATTR` be |
| 452 | set to the string `VALUE`. |
| 453 | |
| 454 | - "`!ATTR`" requires that the attribute `ATTR` be |
| 455 | unspecified. |
| 456 | |
| 457 | + |
| 458 | Note that when matching against a tree object, attributes are still |
| 459 | obtained from working tree, not from the given tree object. |
| 460 | |
| 461 | exclude;; |
| 462 | After a path matches any non-exclude pathspec, it will be run |
| 463 | through all exclude pathspecs (magic signature: `!` or its |
| 464 | synonym `^`). If it matches, the path is ignored. When there |
| 465 | is no non-exclude pathspec, the exclusion is applied to the |
| 466 | result set as if invoked without any pathspec. |
| 467 | -- |
| 468 | |
| 469 | [[def_parent]]parent:: |
| 470 | A <<def_commit_object,commit object>> contains a (possibly empty) list |
| 471 | of the logical predecessor(s) in the line of development, i.e. its |
| 472 | parents. |
| 473 | |
| 474 | [[def_peel]]peel:: |
| 475 | The action of recursively <<def_dereference,dereferencing>> a |
| 476 | <<def_tag_object,tag object>>. |
| 477 | |
| 478 | [[def_pickaxe]]pickaxe:: |
| 479 | The term <<def_pickaxe,pickaxe>> refers to an option to the diffcore |
| 480 | routines that help select changes that add or delete a given text |
| 481 | string. With the `--pickaxe-all` option, it can be used to view the full |
| 482 | <<def_changeset,changeset>> that introduced or removed, say, a |
| 483 | particular line of text. See linkgit:git-diff[1]. |
| 484 | |
| 485 | [[def_plumbing]]plumbing:: |
| 486 | Cute name for <<def_core_git,core Git>>. |
| 487 | |
| 488 | [[def_porcelain]]porcelain:: |
| 489 | Cute name for programs and program suites depending on |
| 490 | <<def_core_git,core Git>>, presenting a high level access to |
| 491 | core Git. Porcelains expose more of a <<def_SCM,SCM>> |
| 492 | interface than the <<def_plumbing,plumbing>>. |
| 493 | |
| 494 | [[def_per_worktree_ref]]per-worktree ref:: |
| 495 | Refs that are per-<<def_worktree,worktree>>, rather than |
| 496 | global. This is presently only <<def_HEAD,HEAD>> and any refs |
| 497 | that start with `refs/bisect/`, but might later include other |
| 498 | unusual refs. |
| 499 | |
| 500 | [[def_pseudoref]]pseudoref:: |
| 501 | A ref that has different semantics than normal refs. These refs can be |
| 502 | read via normal Git commands, but cannot be written to by commands like |
| 503 | linkgit:git-update-ref[1]. |
| 504 | + |
| 505 | The following pseudorefs are known to Git: |
| 506 | |
| 507 | - `FETCH_HEAD` is written by linkgit:git-fetch[1] or linkgit:git-pull[1]. It |
| 508 | may refer to multiple object IDs. Each object ID is annotated with metadata |
| 509 | indicating where it was fetched from and its fetch status. |
| 510 | |
| 511 | - `MERGE_HEAD` is written by linkgit:git-merge[1] when resolving merge |
| 512 | conflicts. It contains all commit IDs which are being merged. |
| 513 | |
| 514 | [[def_pull]]pull:: |
| 515 | Pulling a <<def_branch,branch>> means to <<def_fetch,fetch>> it and |
| 516 | <<def_merge,merge>> it. See also linkgit:git-pull[1]. |
| 517 | |
| 518 | [[def_push]]push:: |
| 519 | Pushing a <<def_branch,branch>> means to get the branch's |
| 520 | <<def_head_ref,head ref>> from a remote <<def_repository,repository>>, |
| 521 | find out if it is an ancestor to the branch's local |
| 522 | head ref, and in that case, putting all |
| 523 | objects, which are <<def_reachable,reachable>> from the local |
| 524 | head ref, and which are missing from the remote |
| 525 | repository, into the remote |
| 526 | <<def_object_database,object database>>, and updating the remote |
| 527 | head ref. If the remote <<def_head,head>> is not an |
| 528 | ancestor to the local head, the push fails. |
| 529 | |
| 530 | [[def_reachable]]reachable:: |
| 531 | All of the ancestors of a given <<def_commit,commit>> are said to be |
| 532 | "reachable" from that commit. More |
| 533 | generally, one <<def_object,object>> is reachable from |
| 534 | another if we can reach the one from the other by a <<def_chain,chain>> |
| 535 | that follows <<def_tag,tags>> to whatever they tag, |
| 536 | <<def_commit_object,commits>> to their parents or trees, and |
| 537 | <<def_tree_object,trees>> to the trees or <<def_blob_object,blobs>> |
| 538 | that they contain. |
| 539 | |
| 540 | [[def_reachability_bitmap]]reachability bitmaps:: |
| 541 | Reachability bitmaps store information about the |
| 542 | <<def_reachable,reachability>> of a selected set of commits in |
| 543 | a packfile, or a multi-pack index (MIDX), to speed up object search. |
| 544 | The bitmaps are stored in a ".bitmap" file. A repository may have at |
| 545 | most one bitmap file in use. The bitmap file may belong to either one |
| 546 | pack, or the repository's multi-pack index (if it exists). |
| 547 | |
| 548 | [[def_rebase]]rebase:: |
| 549 | To reapply a series of changes from a <<def_branch,branch>> to a |
| 550 | different base, and reset the <<def_head,head>> of that branch |
| 551 | to the result. |
| 552 | |
| 553 | [[def_ref]]ref:: |
| 554 | A name that points to an <<def_object_name,object name>> or |
| 555 | another ref (the latter is called a <<def_symref,symbolic ref>>). |
| 556 | For convenience, a ref can sometimes be abbreviated when used |
| 557 | as an argument to a Git command; see linkgit:gitrevisions[7] |
| 558 | for details. |
| 559 | Refs are stored in the <<def_repository,repository>>. |
| 560 | + |
| 561 | The ref namespace is hierarchical. |
| 562 | Ref names must either start with `refs/` or be located in the root of |
| 563 | the hierarchy. For the latter, their name must follow these rules: |
| 564 | + |
| 565 | -- |
| 566 | - The name consists of only upper-case characters or underscores. |
| 567 | |
| 568 | - The name ends with "`_HEAD`" or is equal to "`HEAD`". |
| 569 | -- |
| 570 | + |
| 571 | There are some irregular refs in the root of the hierarchy that do not |
| 572 | match these rules. The following list is exhaustive and shall not be |
| 573 | extended in the future: |
| 574 | + |
| 575 | -- |
| 576 | - `AUTO_MERGE` |
| 577 | |
| 578 | - `BISECT_EXPECTED_REV` |
| 579 | |
| 580 | - `NOTES_MERGE_PARTIAL` |
| 581 | |
| 582 | - `NOTES_MERGE_REF` |
| 583 | |
| 584 | - `MERGE_AUTOSTASH` |
| 585 | -- |
| 586 | + |
| 587 | Different subhierarchies are used for different purposes. For example, |
| 588 | the `refs/heads/` hierarchy is used to represent local branches whereas |
| 589 | the `refs/tags/` hierarchy is used to represent local tags.. |
| 590 | |
| 591 | [[def_reflog]]reflog:: |
| 592 | A reflog shows the local "history" of a ref. In other words, |
| 593 | it can tell you what the 3rd last revision in _this_ repository |
| 594 | was, and what was the current state in _this_ repository, |
| 595 | yesterday 9:14pm. See linkgit:git-reflog[1] for details. |
| 596 | |
| 597 | [[def_refspec]]refspec:: |
| 598 | A "refspec" is used by <<def_fetch,fetch>> and |
| 599 | <<def_push,push>> to describe the mapping between remote |
| 600 | <<def_ref,ref>> and local ref. See linkgit:git-fetch[1] or |
| 601 | linkgit:git-push[1] for details. |
| 602 | |
| 603 | [[def_remote]]remote repository:: |
| 604 | A <<def_repository,repository>> which is used to track the same |
| 605 | project but resides somewhere else. To communicate with remotes, |
| 606 | see <<def_fetch,fetch>> or <<def_push,push>>. |
| 607 | |
| 608 | [[def_remote_tracking_branch]]remote-tracking branch:: |
| 609 | A <<def_ref,ref>> that is used to follow changes from another |
| 610 | <<def_repository,repository>>. It typically looks like |
| 611 | 'refs/remotes/foo/bar' (indicating that it tracks a branch named |
| 612 | 'bar' in a remote named 'foo'), and matches the right-hand-side of |
| 613 | a configured fetch <<def_refspec,refspec>>. A remote-tracking |
| 614 | branch should not contain direct modifications or have local |
| 615 | commits made to it. |
| 616 | |
| 617 | [[def_repository]]repository:: |
| 618 | A collection of <<def_ref,refs>> together with an |
| 619 | <<def_object_database,object database>> containing all objects |
| 620 | which are <<def_reachable,reachable>> from the refs, possibly |
| 621 | accompanied by meta data from one or more <<def_porcelain,porcelains>>. A |
| 622 | repository can share an object database with other repositories |
| 623 | via <<def_alternate_object_database,alternates mechanism>>. |
| 624 | |
| 625 | [[def_resolve]]resolve:: |
| 626 | The action of fixing up manually what a failed automatic |
| 627 | <<def_merge,merge>> left behind. |
| 628 | |
| 629 | [[def_revision]]revision:: |
| 630 | Synonym for <<def_commit,commit>> (the noun). |
| 631 | |
| 632 | [[def_rewind]]rewind:: |
| 633 | To throw away part of the development, i.e. to assign the |
| 634 | <<def_head,head>> to an earlier <<def_revision,revision>>. |
| 635 | |
| 636 | [[def_SCM]]SCM:: |
| 637 | Source code management (tool). |
| 638 | |
| 639 | [[def_SHA1]]SHA-1:: |
| 640 | "Secure Hash Algorithm 1"; a cryptographic hash function. |
| 641 | In the context of Git used as a synonym for <<def_object_name,object name>>. |
| 642 | |
| 643 | [[def_shallow_clone]]shallow clone:: |
| 644 | Mostly a synonym to <<def_shallow_repository,shallow repository>> |
| 645 | but the phrase makes it more explicit that it was created by |
| 646 | running `git clone --depth=...` command. |
| 647 | |
| 648 | [[def_shallow_repository]]shallow repository:: |
| 649 | A shallow <<def_repository,repository>> has an incomplete |
| 650 | history some of whose <<def_commit,commits>> have <<def_parent,parents>> cauterized away (in other |
| 651 | words, Git is told to pretend that these commits do not have the |
| 652 | parents, even though they are recorded in the <<def_commit_object,commit |
| 653 | object>>). This is sometimes useful when you are interested only in the |
| 654 | recent history of a project even though the real history recorded in the |
| 655 | upstream is much larger. A shallow repository |
| 656 | is created by giving the `--depth` option to linkgit:git-clone[1], and |
| 657 | its history can be later deepened with linkgit:git-fetch[1]. |
| 658 | |
| 659 | [[def_stash]]stash entry:: |
| 660 | An <<def_object,object>> used to temporarily store the contents of a |
| 661 | <<def_dirty,dirty>> working directory and the index for future reuse. |
| 662 | |
| 663 | [[def_submodule]]submodule:: |
| 664 | A <<def_repository,repository>> that holds the history of a |
| 665 | separate project inside another repository (the latter of |
| 666 | which is called <<def_superproject, superproject>>). |
| 667 | |
| 668 | [[def_superproject]]superproject:: |
| 669 | A <<def_repository,repository>> that references repositories |
| 670 | of other projects in its working tree as <<def_submodule,submodules>>. |
| 671 | The superproject knows about the names of (but does not hold |
| 672 | copies of) commit objects of the contained submodules. |
| 673 | |
| 674 | [[def_symref]]symref:: |
| 675 | Symbolic reference: instead of containing the <<def_SHA1,SHA-1>> id |
| 676 | itself, it is of the format 'ref: refs/some/thing' and when referenced, |
| 677 | it recursively <<def_dereference,dereferences>> to this reference. |
| 678 | '<<def_HEAD,HEAD>>' is a prime example of a symref. Symbolic references |
| 679 | are manipulated with the linkgit:git-symbolic-ref[1] command. |
| 680 | |
| 681 | [[def_tag]]tag:: |
| 682 | A <<def_ref,ref>> under `refs/tags/` namespace that points to an |
| 683 | object of an arbitrary type (typically a tag points to either a |
| 684 | <<def_tag_object,tag>> or a <<def_commit_object,commit object>>). |
| 685 | In contrast to a <<def_head,head>>, a tag is not updated by |
| 686 | the `commit` command. A Git tag has nothing to do with a Lisp |
| 687 | tag (which would be called an <<def_object_type,object type>> |
| 688 | in Git's context). A tag is most typically used to mark a particular |
| 689 | point in the commit ancestry <<def_chain,chain>>. |
| 690 | |
| 691 | [[def_tag_object]]tag object:: |
| 692 | An <<def_object,object>> containing a <<def_ref,ref>> pointing to |
| 693 | another object, which can contain a message just like a |
| 694 | <<def_commit_object,commit object>>. It can also contain a (PGP) |
| 695 | signature, in which case it is called a "signed tag object". |
| 696 | |
| 697 | [[def_topic_branch]]topic branch:: |
| 698 | A regular Git <<def_branch,branch>> that is used by a developer to |
| 699 | identify a conceptual line of development. Since branches are very easy |
| 700 | and inexpensive, it is often desirable to have several small branches |
| 701 | that each contain very well defined concepts or small incremental yet |
| 702 | related changes. |
| 703 | |
| 704 | [[def_trailer]]trailer:: |
| 705 | Key-value metadata. Trailers are optionally found at the end of |
| 706 | a commit message. Might be called "footers" or "tags" in other |
| 707 | communities. See linkgit:git-interpret-trailers[1]. |
| 708 | |
| 709 | [[def_tree]]tree:: |
| 710 | Either a <<def_working_tree,working tree>>, or a <<def_tree_object,tree |
| 711 | object>> together with the dependent <<def_blob_object,blob>> and tree objects |
| 712 | (i.e. a stored representation of a working tree). |
| 713 | |
| 714 | [[def_tree_object]]tree object:: |
| 715 | An <<def_object,object>> containing a list of file names and modes along |
| 716 | with refs to the associated blob and/or tree objects. A |
| 717 | <<def_tree,tree>> is equivalent to a <<def_directory,directory>>. |
| 718 | |
| 719 | [[def_tree-ish]]tree-ish (also treeish):: |
| 720 | A <<def_tree_object,tree object>> or an <<def_object,object>> that can |
| 721 | be recursively <<def_dereference,dereferenced>> to a tree object. |
| 722 | Dereferencing a <<def_commit_object,commit object>> yields the tree |
| 723 | object corresponding to the <<def_revision,revision>>'s top |
| 724 | <<def_directory,directory>>. |
| 725 | The following are all tree-ishes: |
| 726 | a <<def_commit-ish,commit-ish>>, |
| 727 | a tree object, |
| 728 | a <<def_tag_object,tag object>> that points to a tree object, |
| 729 | a tag object that points to a tag object that points to a tree |
| 730 | object, |
| 731 | etc. |
| 732 | |
| 733 | [[def_unborn]]unborn:: |
| 734 | The <<def_HEAD,HEAD>> can point at a <<def_branch,branch>> |
| 735 | that does not yet exist and that does not have any commit on |
| 736 | it yet, and such a branch is called an unborn branch. The |
| 737 | most typical way users encounter an unborn branch is by |
| 738 | creating a repository anew without cloning from elsewhere. |
| 739 | The HEAD would point at the 'main' (or 'master', depending |
| 740 | on your configuration) branch that is yet to be born. Also |
| 741 | some operations can get you on an unborn branch with their |
| 742 | <<def_orphan,orphan>> option. |
| 743 | |
| 744 | |
| 745 | [[def_unmerged_index]]unmerged index:: |
| 746 | An <<def_index,index>> which contains unmerged |
| 747 | <<def_index_entry,index entries>>. |
| 748 | |
| 749 | [[def_unreachable_object]]unreachable object:: |
| 750 | An <<def_object,object>> which is not <<def_reachable,reachable>> from a |
| 751 | <<def_branch,branch>>, <<def_tag,tag>>, or any other reference. |
| 752 | |
| 753 | [[def_upstream_branch]]upstream branch:: |
| 754 | The default <<def_branch,branch>> that is merged into the branch in |
| 755 | question (or the branch in question is rebased onto). It is configured |
| 756 | via branch.<name>.remote and branch.<name>.merge. If the upstream branch |
| 757 | of 'A' is 'origin/B' sometimes we say "'A' is tracking 'origin/B'". |
| 758 | |
| 759 | [[def_working_tree]]working tree:: |
| 760 | The tree of actual checked out files. The working tree normally |
| 761 | contains the contents of the <<def_HEAD,HEAD>> commit's tree, |
| 762 | plus any local changes that you have made but not yet committed. |
| 763 | |
| 764 | [[def_worktree]]worktree:: |
| 765 | A repository can have zero (i.e. bare repository) or one or |
| 766 | more worktrees attached to it. One "worktree" consists of a |
| 767 | "working tree" and repository metadata, most of which are |
| 768 | shared among other worktrees of a single repository, and |
| 769 | some of which are maintained separately per worktree |
| 770 | (e.g. the index, HEAD and pseudorefs like MERGE_HEAD, |
| 771 | per-worktree refs and per-worktree configuration file). |