| [[def_alternate_object_database]]alternate object database:: |
| Via the alternates mechanism, a <<def_repository,repository>> |
| can inherit part of its <<def_object_database,object database>> |
| from another object database, which is called "alternate". |
| |
| [[def_bare_repository]]bare repository:: |
| A bare repository is normally an appropriately |
| named <<def_directory,directory>> with a `.git` suffix that does not |
| have a locally checked-out copy of any of the files under |
| revision control. That is, all of the Git |
| administrative and control files that would normally be present in the |
| hidden `.git` sub-directory are directly present in the |
| `repository.git` directory instead, |
| and no other files are present and checked out. Usually publishers of |
| public repositories make bare repositories available. |
| |
| [[def_blob_object]]blob object:: |
| Untyped <<def_object,object>>, e.g. the contents of a file. |
| |
| [[def_branch]]branch:: |
| A "branch" is an active line of development. The most recent |
| <<def_commit,commit>> on a branch is referred to as the tip of |
| that branch. The tip of the branch is referenced by a branch |
| <<def_head,head>>, which moves forward as additional development |
| is done on the branch. A single Git |
| <<def_repository,repository>> can track an arbitrary number of |
| branches, but your <<def_working_tree,working tree>> is |
| associated with just one of them (the "current" or "checked out" |
| branch), and <<def_HEAD,HEAD>> points to that branch. |
| |
| [[def_cache]]cache:: |
| Obsolete for: <<def_index,index>>. |
| |
| [[def_chain]]chain:: |
| A list of objects, where each <<def_object,object>> in the list contains |
| a reference to its successor (for example, the successor of a |
| <<def_commit,commit>> could be one of its <<def_parent,parents>>). |
| |
| [[def_changeset]]changeset:: |
| BitKeeper/cvsps speak for "<<def_commit,commit>>". Since Git does not |
| store changes, but states, it really does not make sense to use the term |
| "changesets" with Git. |
| |
| [[def_checkout]]checkout:: |
| The action of updating all or part of the |
| <<def_working_tree,working tree>> with a <<def_tree_object,tree object>> |
| or <<def_blob_object,blob>> from the |
| <<def_object_database,object database>>, and updating the |
| <<def_index,index>> and <<def_HEAD,HEAD>> if the whole working tree has |
| been pointed at a new <<def_branch,branch>>. |
| |
| [[def_cherry-picking]]cherry-picking:: |
| In <<def_SCM,SCM>> jargon, "cherry pick" means to choose a subset of |
| changes out of a series of changes (typically commits) and record them |
| as a new series of changes on top of a different codebase. In Git, this is |
| performed by the "git cherry-pick" command to extract the change introduced |
| by an existing <<def_commit,commit>> and to record it based on the tip |
| of the current <<def_branch,branch>> as a new commit. |
| |
| [[def_clean]]clean:: |
| A <<def_working_tree,working tree>> is clean, if it |
| corresponds to the <<def_revision,revision>> referenced by the current |
| <<def_head,head>>. Also see "<<def_dirty,dirty>>". |
| |
| [[def_commit]]commit:: |
| As a noun: A single point in the |
| Git history; the entire history of a project is represented as a |
| set of interrelated commits. The word "commit" is often |
| used by Git in the same places other revision control systems |
| use the words "revision" or "version". Also used as a short |
| hand for <<def_commit_object,commit object>>. |
| + |
| As a verb: The action of storing a new snapshot of the project's |
| state in the Git history, by creating a new commit representing the current |
| state of the <<def_index,index>> and advancing <<def_HEAD,HEAD>> |
| to point at the new commit. |
| |
| [[def_commit_object]]commit object:: |
| An <<def_object,object>> which contains the information about a |
| particular <<def_revision,revision>>, such as <<def_parent,parents>>, committer, |
| author, date and the <<def_tree_object,tree object>> which corresponds |
| to the top <<def_directory,directory>> of the stored |
| revision. |
| |
| [[def_core_git]]core Git:: |
| Fundamental data structures and utilities of Git. Exposes only limited |
| source code management tools. |
| |
| [[def_DAG]]DAG:: |
| Directed acyclic graph. The <<def_commit_object,commit objects>> form a |
| directed acyclic graph, because they have parents (directed), and the |
| graph of commit objects is acyclic (there is no <<def_chain,chain>> |
| which begins and ends with the same <<def_object,object>>). |
| |
| [[def_dangling_object]]dangling object:: |
| An <<def_unreachable_object,unreachable object>> which is not |
| <<def_reachable,reachable>> even from other unreachable objects; a |
| dangling object has no references to it from any |
| reference or <<def_object,object>> in the <<def_repository,repository>>. |
| |
| [[def_detached_HEAD]]detached HEAD:: |
| Normally the <<def_HEAD,HEAD>> stores the name of a |
| <<def_branch,branch>>, and commands that operate on the |
| history HEAD represents operate on the history leading to the |
| tip of the branch the HEAD points at. However, Git also |
| allows you to <<def_checkout,check out>> an arbitrary |
| <<def_commit,commit>> that isn't necessarily the tip of any |
| particular branch. The HEAD in such a state is called |
| "detached". |
| + |
| Note that commands that operate on the history of the current branch |
| (e.g. `git commit` to build a new history on top of it) still work |
| while the HEAD is detached. They update the HEAD to point at the tip |
| of the updated history without affecting any branch. Commands that |
| update or inquire information _about_ the current branch (e.g. `git |
| branch --set-upstream-to` that sets what remote-tracking branch the |
| current branch integrates with) obviously do not work, as there is no |
| (real) current branch to ask about in this state. |
| |
| [[def_directory]]directory:: |
| The list you get with "ls" :-) |
| |
| [[def_dirty]]dirty:: |
| A <<def_working_tree,working tree>> is said to be "dirty" if |
| it contains modifications which have not been <<def_commit,committed>> to the current |
| <<def_branch,branch>>. |
| |
| [[def_evil_merge]]evil merge:: |
| An evil merge is a <<def_merge,merge>> that introduces changes that |
| do not appear in any <<def_parent,parent>>. |
| |
| [[def_fast_forward]]fast-forward:: |
| A fast-forward is a special type of <<def_merge,merge>> where you have a |
| <<def_revision,revision>> and you are "merging" another |
| <<def_branch,branch>>'s changes that happen to be a descendant of what |
| you have. In such these cases, you do not make a new <<def_merge,merge>> |
| <<def_commit,commit>> but instead just update to his |
| revision. This will happen frequently on a |
| <<def_remote_tracking_branch,remote-tracking branch>> of a remote |
| <<def_repository,repository>>. |
| |
| [[def_fetch]]fetch:: |
| Fetching a <<def_branch,branch>> means to get the |
| branch's <<def_head_ref,head ref>> from a remote |
| <<def_repository,repository>>, to find out which objects are |
| missing from the local <<def_object_database,object database>>, |
| and to get them, too. See also linkgit:git-fetch[1]. |
| |
| [[def_file_system]]file system:: |
| Linus Torvalds originally designed Git to be a user space file system, |
| i.e. the infrastructure to hold files and directories. That ensured the |
| efficiency and speed of Git. |
| |
| [[def_git_archive]]Git archive:: |
| Synonym for <<def_repository,repository>> (for arch people). |
| |
| [[def_gitfile]]gitfile:: |
| A plain file `.git` at the root of a working tree that |
| points at the directory that is the real repository. |
| |
| [[def_grafts]]grafts:: |
| Grafts enables two otherwise different lines of development to be joined |
| together by recording fake ancestry information for commits. This way |
| you can make Git pretend the set of <<def_parent,parents>> a <<def_commit,commit>> has |
| is different from what was recorded when the commit was |
| created. Configured via the `.git/info/grafts` file. |
| |
| [[def_hash]]hash:: |
| In Git's context, synonym for <<def_object_name,object name>>. |
| |
| [[def_head]]head:: |
| A <<def_ref,named reference>> to the <<def_commit,commit>> at the tip of a |
| <<def_branch,branch>>. Heads are stored in a file in |
| `$GIT_DIR/refs/heads/` directory, except when using packed refs. (See |
| linkgit:git-pack-refs[1].) |
| |
| [[def_HEAD]]HEAD:: |
| The current <<def_branch,branch>>. In more detail: Your <<def_working_tree, |
| working tree>> is normally derived from the state of the tree |
| referred to by HEAD. HEAD is a reference to one of the |
| <<def_head,heads>> in your repository, except when using a |
| <<def_detached_HEAD,detached HEAD>>, in which case it directly |
| references an arbitrary commit. |
| |
| [[def_head_ref]]head ref:: |
| A synonym for <<def_head,head>>. |
| |
| [[def_hook]]hook:: |
| During the normal execution of several Git commands, call-outs are made |
| to optional scripts that allow a developer to add functionality or |
| checking. Typically, the hooks allow for a command to be pre-verified |
| and potentially aborted, and allow for a post-notification after the |
| operation is done. The hook scripts are found in the |
| `$GIT_DIR/hooks/` directory, and are enabled by simply |
| removing the `.sample` suffix from the filename. In earlier versions |
| of Git you had to make them executable. |
| |
| [[def_index]]index:: |
| A collection of files with stat information, whose contents are stored |
| as objects. The index is a stored version of your |
| <<def_working_tree,working tree>>. Truth be told, it can also contain a second, and even |
| a third version of a working tree, which are used |
| when <<def_merge,merging>>. |
| |
| [[def_index_entry]]index entry:: |
| The information regarding a particular file, stored in the |
| <<def_index,index>>. An index entry can be unmerged, if a |
| <<def_merge,merge>> was started, but not yet finished (i.e. if |
| the index contains multiple versions of that file). |
| |
| [[def_master]]master:: |
| The default development <<def_branch,branch>>. Whenever you |
| create a Git <<def_repository,repository>>, a branch named |
| "master" is created, and becomes the active branch. In most |
| cases, this contains the local development, though that is |
| purely by convention and is not required. |
| |
| [[def_merge]]merge:: |
| As a verb: To bring the contents of another |
| <<def_branch,branch>> (possibly from an external |
| <<def_repository,repository>>) into the current branch. In the |
| case where the merged-in branch is from a different repository, |
| this is done by first <<def_fetch,fetching>> the remote branch |
| and then merging the result into the current branch. This |
| combination of fetch and merge operations is called a |
| <<def_pull,pull>>. Merging is performed by an automatic process |
| that identifies changes made since the branches diverged, and |
| then applies all those changes together. In cases where changes |
| conflict, manual intervention may be required to complete the |
| merge. |
| + |
| As a noun: unless it is a <<def_fast_forward,fast-forward>>, a |
| successful merge results in the creation of a new <<def_commit,commit>> |
| representing the result of the merge, and having as |
| <<def_parent,parents>> the tips of the merged <<def_branch,branches>>. |
| This commit is referred to as a "merge commit", or sometimes just a |
| "merge". |
| |
| [[def_object]]object:: |
| The unit of storage in Git. It is uniquely identified by the |
| <<def_SHA1,SHA-1>> of its contents. Consequently, an |
| object can not be changed. |
| |
| [[def_object_database]]object database:: |
| Stores a set of "objects", and an individual <<def_object,object>> is |
| identified by its <<def_object_name,object name>>. The objects usually |
| live in `$GIT_DIR/objects/`. |
| |
| [[def_object_identifier]]object identifier:: |
| Synonym for <<def_object_name,object name>>. |
| |
| [[def_object_name]]object name:: |
| The unique identifier of an <<def_object,object>>. The |
| object name is usually represented by a 40 character |
| hexadecimal string. Also colloquially called <<def_SHA1,SHA-1>>. |
| |
| [[def_object_type]]object type:: |
| One of the identifiers "<<def_commit_object,commit>>", |
| "<<def_tree_object,tree>>", "<<def_tag_object,tag>>" or |
| "<<def_blob_object,blob>>" describing the type of an |
| <<def_object,object>>. |
| |
| [[def_octopus]]octopus:: |
| To <<def_merge,merge>> more than two <<def_branch,branches>>. |
| |
| [[def_origin]]origin:: |
| The default upstream <<def_repository,repository>>. Most projects have |
| at least one upstream project which they track. By default |
| 'origin' is used for that purpose. New upstream updates |
| will be fetched into <<def_remote_tracking_branch,remote-tracking branches>> named |
| origin/name-of-upstream-branch, which you can see using |
| `git branch -r`. |
| |
| [[def_pack]]pack:: |
| A set of objects which have been compressed into one file (to save space |
| or to transmit them efficiently). |
| |
| [[def_pack_index]]pack index:: |
| The list of identifiers, and other information, of the objects in a |
| <<def_pack,pack>>, to assist in efficiently accessing the contents of a |
| pack. |
| |
| [[def_pathspec]]pathspec:: |
| Pattern used to limit paths in Git commands. |
| + |
| Pathspecs are used on the command line of "git ls-files", "git |
| ls-tree", "git add", "git grep", "git diff", "git checkout", |
| and many other commands to |
| limit the scope of operations to some subset of the tree or |
| worktree. See the documentation of each command for whether |
| paths are relative to the current directory or toplevel. The |
| pathspec syntax is as follows: |
| + |
| -- |
| |
| * any path matches itself |
| * the pathspec up to the last slash represents a |
| directory prefix. The scope of that pathspec is |
| limited to that subtree. |
| * the rest of the pathspec is a pattern for the remainder |
| of the pathname. Paths relative to the directory |
| prefix will be matched against that pattern using fnmatch(3); |
| in particular, '*' and '?' _can_ match directory separators. |
| |
| -- |
| + |
| For example, Documentation/*.jpg will match all .jpg files |
| in the Documentation subtree, |
| including Documentation/chapter_1/figure_1.jpg. |
| + |
| A pathspec that begins with a colon `:` has special meaning. In the |
| short form, the leading colon `:` is followed by zero or more "magic |
| signature" letters (which optionally is terminated by another colon `:`), |
| and the remainder is the pattern to match against the path. The optional |
| colon that terminates the "magic signature" can be omitted if the pattern |
| begins with a character that cannot be a "magic signature" and is not a |
| colon. |
| + |
| In the long form, the leading colon `:` is followed by a open |
| parenthesis `(`, a comma-separated list of zero or more "magic words", |
| and a close parentheses `)`, and the remainder is the pattern to match |
| against the path. |
| + |
| The "magic signature" consists of an ASCII symbol that is not |
| alphanumeric. Currently only the slash `/` is recognized as a |
| "magic signature": it makes the pattern match from the root of |
| the working tree, even when you are running the command from |
| inside a subdirectory. |
| + |
| A pathspec with only a colon means "there is no pathspec". This form |
| should not be combined with other pathspec. |
| |
| [[def_parent]]parent:: |
| A <<def_commit_object,commit object>> contains a (possibly empty) list |
| of the logical predecessor(s) in the line of development, i.e. its |
| parents. |
| |
| [[def_pickaxe]]pickaxe:: |
| The term <<def_pickaxe,pickaxe>> refers to an option to the diffcore |
| routines that help select changes that add or delete a given text |
| string. With the `--pickaxe-all` option, it can be used to view the full |
| <<def_changeset,changeset>> that introduced or removed, say, a |
| particular line of text. See linkgit:git-diff[1]. |
| |
| [[def_plumbing]]plumbing:: |
| Cute name for <<def_core_git,core Git>>. |
| |
| [[def_porcelain]]porcelain:: |
| Cute name for programs and program suites depending on |
| <<def_core_git,core Git>>, presenting a high level access to |
| core Git. Porcelains expose more of a <<def_SCM,SCM>> |
| interface than the <<def_plumbing,plumbing>>. |
| |
| [[def_pull]]pull:: |
| Pulling a <<def_branch,branch>> means to <<def_fetch,fetch>> it and |
| <<def_merge,merge>> it. See also linkgit:git-pull[1]. |
| |
| [[def_push]]push:: |
| Pushing a <<def_branch,branch>> means to get the branch's |
| <<def_head_ref,head ref>> from a remote <<def_repository,repository>>, |
| find out if it is a direct ancestor to the branch's local |
| head ref, and in that case, putting all |
| objects, which are <<def_reachable,reachable>> from the local |
| head ref, and which are missing from the remote |
| repository, into the remote |
| <<def_object_database,object database>>, and updating the remote |
| head ref. If the remote <<def_head,head>> is not an |
| ancestor to the local head, the push fails. |
| |
| [[def_reachable]]reachable:: |
| All of the ancestors of a given <<def_commit,commit>> are said to be |
| "reachable" from that commit. More |
| generally, one <<def_object,object>> is reachable from |
| another if we can reach the one from the other by a <<def_chain,chain>> |
| that follows <<def_tag,tags>> to whatever they tag, |
| <<def_commit_object,commits>> to their parents or trees, and |
| <<def_tree_object,trees>> to the trees or <<def_blob_object,blobs>> |
| that they contain. |
| |
| [[def_rebase]]rebase:: |
| To reapply a series of changes from a <<def_branch,branch>> to a |
| different base, and reset the <<def_head,head>> of that branch |
| to the result. |
| |
| [[def_ref]]ref:: |
| A 40-byte hex representation of a <<def_SHA1,SHA-1>> or a name that |
| denotes a particular <<def_object,object>>. They may be stored in |
| a file under `$GIT_DIR/refs/` directory, or |
| in the `$GIT_DIR/packed-refs` file. |
| |
| [[def_reflog]]reflog:: |
| A reflog shows the local "history" of a ref. In other words, |
| it can tell you what the 3rd last revision in _this_ repository |
| was, and what was the current state in _this_ repository, |
| yesterday 9:14pm. See linkgit:git-reflog[1] for details. |
| |
| [[def_refspec]]refspec:: |
| A "refspec" is used by <<def_fetch,fetch>> and |
| <<def_push,push>> to describe the mapping between remote |
| <<def_ref,ref>> and local ref. |
| |
| [[def_remote_tracking_branch]]remote-tracking branch:: |
| A <<def_ref,ref>> that is used to follow changes from another |
| <<def_repository,repository>>. It typically looks like |
| 'refs/remotes/foo/bar' (indicating that it tracks a branch named |
| 'bar' in a remote named 'foo'), and matches the right-hand-side of |
| a configured fetch <<def_refspec,refspec>>. A remote-tracking |
| branch should not contain direct modifications or have local |
| commits made to it. |
| |
| [[def_repository]]repository:: |
| A collection of <<def_ref,refs>> together with an |
| <<def_object_database,object database>> containing all objects |
| which are <<def_reachable,reachable>> from the refs, possibly |
| accompanied by meta data from one or more <<def_porcelain,porcelains>>. A |
| repository can share an object database with other repositories |
| via <<def_alternate_object_database,alternates mechanism>>. |
| |
| [[def_resolve]]resolve:: |
| The action of fixing up manually what a failed automatic |
| <<def_merge,merge>> left behind. |
| |
| [[def_revision]]revision:: |
| Synonym for <<def_commit,commit>> (the noun). |
| |
| [[def_rewind]]rewind:: |
| To throw away part of the development, i.e. to assign the |
| <<def_head,head>> to an earlier <<def_revision,revision>>. |
| |
| [[def_SCM]]SCM:: |
| Source code management (tool). |
| |
| [[def_SHA1]]SHA-1:: |
| "Secure Hash Algorithm 1"; a cryptographic hash function. |
| In the context of Git used as a synonym for <<def_object_name,object name>>. |
| |
| [[def_shallow_repository]]shallow repository:: |
| A shallow <<def_repository,repository>> has an incomplete |
| history some of whose <<def_commit,commits>> have <<def_parent,parents>> cauterized away (in other |
| words, Git is told to pretend that these commits do not have the |
| parents, even though they are recorded in the <<def_commit_object,commit |
| object>>). This is sometimes useful when you are interested only in the |
| recent history of a project even though the real history recorded in the |
| upstream is much larger. A shallow repository |
| is created by giving the `--depth` option to linkgit:git-clone[1], and |
| its history can be later deepened with linkgit:git-fetch[1]. |
| |
| [[def_symref]]symref:: |
| Symbolic reference: instead of containing the <<def_SHA1,SHA-1>> |
| id itself, it is of the format 'ref: refs/some/thing' and when |
| referenced, it recursively dereferences to this reference. |
| '<<def_HEAD,HEAD>>' is a prime example of a symref. Symbolic |
| references are manipulated with the linkgit:git-symbolic-ref[1] |
| command. |
| |
| [[def_tag]]tag:: |
| A <<def_ref,ref>> under `refs/tags/` namespace that points to an |
| object of an arbitrary type (typically a tag points to either a |
| <<def_tag_object,tag>> or a <<def_commit_object,commit object>>). |
| In contrast to a <<def_head,head>>, a tag is not updated by |
| the `commit` command. A Git tag has nothing to do with a Lisp |
| tag (which would be called an <<def_object_type,object type>> |
| in Git's context). A tag is most typically used to mark a particular |
| point in the commit ancestry <<def_chain,chain>>. |
| |
| [[def_tag_object]]tag object:: |
| An <<def_object,object>> containing a <<def_ref,ref>> pointing to |
| another object, which can contain a message just like a |
| <<def_commit_object,commit object>>. It can also contain a (PGP) |
| signature, in which case it is called a "signed tag object". |
| |
| [[def_topic_branch]]topic branch:: |
| A regular Git <<def_branch,branch>> that is used by a developer to |
| identify a conceptual line of development. Since branches are very easy |
| and inexpensive, it is often desirable to have several small branches |
| that each contain very well defined concepts or small incremental yet |
| related changes. |
| |
| [[def_tree]]tree:: |
| Either a <<def_working_tree,working tree>>, or a <<def_tree_object,tree |
| object>> together with the dependent <<def_blob_object,blob>> and tree objects |
| (i.e. a stored representation of a working tree). |
| |
| [[def_tree_object]]tree object:: |
| An <<def_object,object>> containing a list of file names and modes along |
| with refs to the associated blob and/or tree objects. A |
| <<def_tree,tree>> is equivalent to a <<def_directory,directory>>. |
| |
| [[def_tree-ish]]tree-ish:: |
| A <<def_ref,ref>> pointing to either a <<def_commit_object,commit |
| object>>, a <<def_tree_object,tree object>>, or a <<def_tag_object,tag |
| object>> pointing to a tag or commit or tree object. |
| |
| [[def_unmerged_index]]unmerged index:: |
| An <<def_index,index>> which contains unmerged |
| <<def_index_entry,index entries>>. |
| |
| [[def_unreachable_object]]unreachable object:: |
| An <<def_object,object>> which is not <<def_reachable,reachable>> from a |
| <<def_branch,branch>>, <<def_tag,tag>>, or any other reference. |
| |
| [[def_upstream_branch]]upstream branch:: |
| The default <<def_branch,branch>> that is merged into the branch in |
| question (or the branch in question is rebased onto). It is configured |
| via branch.<name>.remote and branch.<name>.merge. If the upstream branch |
| of 'A' is 'origin/B' sometimes we say "'A' is tracking 'origin/B'". |
| |
| [[def_working_tree]]working tree:: |
| The tree of actual checked out files. The working tree normally |
| contains the contents of the <<def_HEAD,HEAD>> commit's tree, |
| plus any local changes that you have made but not yet committed. |