git-pull(1)


NAME

   git-pull - Fetch from and integrate with another repository or a local
   branch

SYNOPSIS

   git pull [options] [<repository> [<refspec>...]]

DESCRIPTION

   Incorporates changes from a remote repository into the current branch.
   In its default mode, git pull is shorthand for git fetch followed by
   git merge FETCH_HEAD.

   More precisely, git pull runs git fetch with the given parameters and
   calls git merge to merge the retrieved branch heads into the current
   branch. With --rebase, it runs git rebase instead of git merge.

   <repository> should be the name of a remote repository as passed to
   git-fetch(1). <refspec> can name an arbitrary remote ref (for example,
   the name of a tag) or even a collection of refs with corresponding
   remote-tracking branches (e.g., refs/heads/*:refs/remotes/origin/*),
   but usually it is the name of a branch in the remote repository.

   Default values for <repository> and <branch> are read from the "remote"
   and "merge" configuration for the current branch as set by git-
   branch(1) --track.

   Assume the following history exists and the current branch is "master":

                 A---B---C master on origin
                /
           D---E---F---G master
               ^
               origin/master in your repository

   Then "git pull" will fetch and replay the changes from the remote
   master branch since it diverged from the local master (i.e., E) until
   its current commit (C) on top of master and record the result in a new
   commit along with the names of the two parent commits and a log message
   from the user describing the changes.

                 A---B---C origin/master
                /         \
           D---E---F---G---H master

   See git-merge(1) for details, including how conflicts are presented and
   handled.

   In Git 1.7.0 or later, to cancel a conflicting merge, use git reset
   --merge. Warning: In older versions of Git, running git pull with
   uncommitted changes is discouraged: while possible, it leaves you in a
   state that may be hard to back out of in the case of a conflict.

   If any of the remote changes overlap with local uncommitted changes,
   the merge will be automatically cancelled and the work tree untouched.
   It is generally best to get any local changes in working order before
   pulling or stash them away with git-stash(1).

OPTIONS

   -q, --quiet
       This is passed to both underlying git-fetch to squelch reporting of
       during transfer, and underlying git-merge to squelch output during
       merging.

   -v, --verbose
       Pass --verbose to git-fetch and git-merge.

   --[no-]recurse-submodules[=yes|on-demand|no]
       This option controls if new commits of all populated submodules
       should be fetched too (see git-config(1) and gitmodules(5)). That
       might be necessary to get the data needed for merging submodule
       commits, a feature Git learned in 1.7.3. Notice that the result of
       a merge will not be checked out in the submodule, "git submodule
       update" has to be called afterwards to bring the work tree up to
       date with the merge result.

   Options related to merging
   --commit, --no-commit
       Perform the merge and commit the result. This option can be used to
       override --no-commit.

       With --no-commit perform the merge but pretend the merge failed and
       do not autocommit, to give the user a chance to inspect and further
       tweak the merge result before committing.

   --edit, -e, --no-edit
       Invoke an editor before committing successful mechanical merge to
       further edit the auto-generated merge message, so that the user can
       explain and justify the merge. The --no-edit option can be used to
       accept the auto-generated message (this is generally discouraged).

       Older scripts may depend on the historical behaviour of not
       allowing the user to edit the merge log message. They will see an
       editor opened when they run git merge. To make it easier to adjust
       such scripts to the updated behaviour, the environment variable
       GIT_MERGE_AUTOEDIT can be set to no at the beginning of them.

   --ff
       When the merge resolves as a fast-forward, only update the branch
       pointer, without creating a merge commit. This is the default
       behavior.

   --no-ff
       Create a merge commit even when the merge resolves as a
       fast-forward. This is the default behaviour when merging an
       annotated (and possibly signed) tag.

   --ff-only
       Refuse to merge and exit with a non-zero status unless the current
       HEAD is already up-to-date or the merge can be resolved as a
       fast-forward.

   --log[=<n>], --no-log
       In addition to branch names, populate the log message with one-line
       descriptions from at most <n> actual commits that are being merged.
       See also git-fmt-merge-msg(1).

       With --no-log do not list one-line descriptions from the actual
       commits being merged.

   --stat, -n, --no-stat
       Show a diffstat at the end of the merge. The diffstat is also
       controlled by the configuration option merge.stat.

       With -n or --no-stat do not show a diffstat at the end of the
       merge.

   --squash, --no-squash
       Produce the working tree and index state as if a real merge
       happened (except for the merge information), but do not actually
       make a commit, move the HEAD, or record $GIT_DIR/MERGE_HEAD (to
       cause the next git commit command to create a merge commit). This
       allows you to create a single commit on top of the current branch
       whose effect is the same as merging another branch (or more in case
       of an octopus).

       With --no-squash perform the merge and commit the result. This
       option can be used to override --squash.

   -s <strategy>, --strategy=<strategy>
       Use the given merge strategy; can be supplied more than once to
       specify them in the order they should be tried. If there is no -s
       option, a built-in list of strategies is used instead (git
       merge-recursive when merging a single head, git merge-octopus
       otherwise).

   -X <option>, --strategy-option=<option>
       Pass merge strategy specific option through to the merge strategy.

   --verify-signatures, --no-verify-signatures
       Verify that the tip commit of the side branch being merged is
       signed with a valid key, i.e. a key that has a valid uid: in the
       default trust model, this means the signing key has been signed by
       a trusted key. If the tip commit of the side branch is not signed
       with a valid key, the merge is aborted.

   --summary, --no-summary
       Synonyms to --stat and --no-stat; these are deprecated and will be
       removed in the future.

   --allow-unrelated-histories
       By default, git merge command refuses to merge histories that do
       not share a common ancestor. This option can be used to override
       this safety when merging histories of two projects that started
       their lives independently. As that is a very rare occasion, no
       configuration variable to enable this by default exists and will
       not be added.

   -r, --rebase[=false|true|preserve|interactive]
       When true, rebase the current branch on top of the upstream branch
       after fetching. If there is a remote-tracking branch corresponding
       to the upstream branch and the upstream branch was rebased since
       last fetched, the rebase uses that information to avoid rebasing
       non-local changes.

       When set to preserve, rebase with the --preserve-merges option
       passed to git rebase so that locally created merge commits will not
       be flattened.

       When false, merge the current branch into the upstream branch.

       When interactive, enable the interactive mode of rebase.

       See pull.rebase, branch.<name>.rebase and branch.autoSetupRebase in
       git-config(1) if you want to make git pull always use --rebase
       instead of merging.

           Note
           This is a potentially dangerous mode of operation. It rewrites
           history, which does not bode well when you published that
           history already. Do not use this option unless you have read
           git-rebase(1) carefully.

   --no-rebase
       Override earlier --rebase.

   --autostash, --no-autostash
       Before starting rebase, stash local modifications away (see git-
       stash(1)) if needed, and apply the stash when done.  --no-autostash
       is useful to override the rebase.autoStash configuration variable
       (see git-config(1)).

       This option is only valid when "--rebase" is used.

   Options related to fetching
   --all
       Fetch all remotes.

   -a, --append
       Append ref names and object names of fetched refs to the existing
       contents of .git/FETCH_HEAD. Without this option old data in
       .git/FETCH_HEAD will be overwritten.

   --depth=<depth>
       Limit fetching to the specified number of commits from the tip of
       each remote branch history. If fetching to a shallow repository
       created by git clone with --depth=<depth> option (see git-
       clone(1)), deepen or shorten the history to the specified number of
       commits. Tags for the deepened commits are not fetched.

   --unshallow
       If the source repository is complete, convert a shallow repository
       to a complete one, removing all the limitations imposed by shallow
       repositories.

       If the source repository is shallow, fetch as much as possible so
       that the current repository has the same history as the source
       repository.

   --update-shallow
       By default when fetching from a shallow repository, git fetch
       refuses refs that require updating .git/shallow. This option
       updates .git/shallow and accept such refs.

   -f, --force
       When git fetch is used with <rbranch>:<lbranch> refspec, it refuses
       to update the local branch <lbranch> unless the remote branch
       <rbranch> it fetches is a descendant of <lbranch>. This option
       overrides that check.

   -k, --keep
       Keep downloaded pack.

   --no-tags
       By default, tags that point at objects that are downloaded from the
       remote repository are fetched and stored locally. This option
       disables this automatic tag following. The default behavior for a
       remote may be specified with the remote.<name>.tagOpt setting. See
       git-config(1).

   -u, --update-head-ok
       By default git fetch refuses to update the head which corresponds
       to the current branch. This flag disables the check. This is purely
       for the internal use for git pull to communicate with git fetch,
       and unless you are implementing your own Porcelain you are not
       supposed to use it.

   --upload-pack <upload-pack>
       When given, and the repository to fetch from is handled by git
       fetch-pack, --exec=<upload-pack> is passed to the command to
       specify non-default path for the command run on the other end.

   --progress
       Progress status is reported on the standard error stream by default
       when it is attached to a terminal, unless -q is specified. This
       flag forces progress status even if the standard error stream is
       not directed to a terminal.

   -4, --ipv4
       Use IPv4 addresses only, ignoring IPv6 addresses.

   -6, --ipv6
       Use IPv6 addresses only, ignoring IPv4 addresses.

   <repository>
       The "remote" repository that is the source of a fetch or pull
       operation. This parameter can be either a URL (see the section GIT
       URLS below) or the name of a remote (see the section REMOTES
       below).

   <refspec>
       Specifies which refs to fetch and which local refs to update. When
       no <refspec>s appear on the command line, the refs to fetch are
       read from remote.<repository>.fetch variables instead (see git-
       fetch(1)).

       The format of a <refspec> parameter is an optional plus +, followed
       by the source ref <src>, followed by a colon :, followed by the
       destination ref <dst>. The colon can be omitted when <dst> is
       empty.

       tag <tag> means the same as refs/tags/<tag>:refs/tags/<tag>; it
       requests fetching everything up to the given tag.

       The remote ref that matches <src> is fetched, and if <dst> is not
       empty string, the local ref that matches it is fast-forwarded using
       <src>. If the optional plus + is used, the local ref is updated
       even if it does not result in a fast-forward update.

           Note
           When the remote branch you want to fetch is known to be rewound
           and rebased regularly, it is expected that its new tip will not
           be descendant of its previous tip (as stored in your
           remote-tracking branch the last time you fetched). You would
           want to use the + sign to indicate non-fast-forward updates
           will be needed for such branches. There is no way to determine
           or declare that a branch will be made available in a repository
           with this behavior; the pulling user simply must know this is
           the expected usage pattern for a branch.

           Note
           There is a difference between listing multiple <refspec>
           directly on git pull command line and having multiple
           remote.<repository>.fetch entries in your configuration for a
           <repository> and running a git pull command without any
           explicit <refspec> parameters. <refspec>s listed explicitly on
           the command line are always merged into the current branch
           after fetching. In other words, if you list more than one
           remote ref, git pull will create an Octopus merge. On the other
           hand, if you do not list any explicit <refspec> parameter on
           the command line, git pull will fetch all the <refspec>s it
           finds in the remote.<repository>.fetch configuration and merge
           only the first <refspec> found into the current branch. This is
           because making an Octopus from remote refs is rarely done,
           while keeping track of multiple remote heads in one-go by
           fetching more than one is often useful.

GIT URLS

   In general, URLs contain information about the transport protocol, the
   address of the remote server, and the path to the repository. Depending
   on the transport protocol, some of this information may be absent.

   Git supports ssh, git, http, and https protocols (in addition, ftp, and
   ftps can be used for fetching, but this is inefficient and deprecated;
   do not use it).

   The native transport (i.e. git:// URL) does no authentication and
   should be used with caution on unsecured networks.

   The following syntaxes may be used with them:

   *   ssh://[user@]host.xz[:port]/path/to/repo.git/

   *   git://host.xz[:port]/path/to/repo.git/

   *   http[s]://host.xz[:port]/path/to/repo.git/

   *   ftp[s]://host.xz[:port]/path/to/repo.git/

   An alternative scp-like syntax may also be used with the ssh protocol:

   *   [user@]host.xz:path/to/repo.git/

   This syntax is only recognized if there are no slashes before the first
   colon. This helps differentiate a local path that contains a colon. For
   example the local path foo:bar could be specified as an absolute path
   or ./foo:bar to avoid being misinterpreted as an ssh url.

   The ssh and git protocols additionally support ~username expansion:

   *   ssh://[user@]host.xz[:port]/~[user]/path/to/repo.git/

   *   git://host.xz[:port]/~[user]/path/to/repo.git/

   *   [user@]host.xz:/~[user]/path/to/repo.git/

   For local repositories, also supported by Git natively, the following
   syntaxes may be used:

   *   /path/to/repo.git/

   *   file:///path/to/repo.git/

   These two syntaxes are mostly equivalent, except when cloning, when the
   former implies --local option. See git-clone(1) for details.

   When Git doesn't know how to handle a certain transport protocol, it
   attempts to use the remote-<transport> remote helper, if one exists. To
   explicitly request a remote helper, the following syntax may be used:

   *   <transport>::<address>

   where <address> may be a path, a server and path, or an arbitrary
   URL-like string recognized by the specific remote helper being invoked.
   See gitremote-helpers(1) for details.

   If there are a large number of similarly-named remote repositories and
   you want to use a different format for them (such that the URLs you use
   will be rewritten into URLs that work), you can create a configuration
   section of the form:

               [url "<actual url base>"]
                       insteadOf = <other url base>

   For example, with this:

               [url "git://git.host.xz/"]
                       insteadOf = host.xz:/path/to/
                       insteadOf = work:

   a URL like "work:repo.git" or like "host.xz:/path/to/repo.git" will be
   rewritten in any context that takes a URL to be
   "git://git.host.xz/repo.git".

   If you want to rewrite URLs for push only, you can create a
   configuration section of the form:

               [url "<actual url base>"]
                       pushInsteadOf = <other url base>

   For example, with this:

               [url "ssh://example.org/"]
                       pushInsteadOf = git://example.org/

   a URL like "git://example.org/path/to/repo.git" will be rewritten to
   "ssh://example.org/path/to/repo.git" for pushes, but pulls will still
   use the original URL.

REMOTES

   The name of one of the following can be used instead of a URL as
   <repository> argument:

   *   a remote in the Git configuration file: $GIT_DIR/config,

   *   a file in the $GIT_DIR/remotes directory, or

   *   a file in the $GIT_DIR/branches directory.

   All of these also allow you to omit the refspec from the command line
   because they each contain a refspec which git will use by default.

   Named remote in configuration file
   You can choose to provide the name of a remote which you had previously
   configured using git-remote(1), git-config(1) or even by a manual edit
   to the $GIT_DIR/config file. The URL of this remote will be used to
   access the repository. The refspec of this remote will be used by
   default when you do not provide a refspec on the command line. The
   entry in the config file would appear like this:

               [remote "<name>"]
                       url = <url>
                       pushurl = <pushurl>
                       push = <refspec>
                       fetch = <refspec>

   The <pushurl> is used for pushes only. It is optional and defaults to
   <url>.

   Named file in $GIT_DIR/remotes
   You can choose to provide the name of a file in $GIT_DIR/remotes. The
   URL in this file will be used to access the repository. The refspec in
   this file will be used as default when you do not provide a refspec on
   the command line. This file should have the following format:

               URL: one of the above URL format
               Push: <refspec>
               Pull: <refspec>

   Push: lines are used by git push and Pull: lines are used by git pull
   and git fetch. Multiple Push: and Pull: lines may be specified for
   additional branch mappings.

   Named file in $GIT_DIR/branches
   You can choose to provide the name of a file in $GIT_DIR/branches. The
   URL in this file will be used to access the repository. This file
   should have the following format:

               <url>#<head>

   <url> is required; #<head> is optional.

   Depending on the operation, git will use one of the following refspecs,
   if you don't provide one on the command line. <branch> is the name of
   this file in $GIT_DIR/branches and <head> defaults to master.

   git fetch uses:

               refs/heads/<head>:refs/heads/<branch>

   git push uses:

               HEAD:refs/heads/<head>

MERGE STRATEGIES

   The merge mechanism (git merge and git pull commands) allows the
   backend merge strategies to be chosen with -s option. Some strategies
   can also take their own options, which can be passed by giving
   -X<option> arguments to git merge and/or git pull.

   resolve
       This can only resolve two heads (i.e. the current branch and
       another branch you pulled from) using a 3-way merge algorithm. It
       tries to carefully detect criss-cross merge ambiguities and is
       considered generally safe and fast.

   recursive
       This can only resolve two heads using a 3-way merge algorithm. When
       there is more than one common ancestor that can be used for 3-way
       merge, it creates a merged tree of the common ancestors and uses
       that as the reference tree for the 3-way merge. This has been
       reported to result in fewer merge conflicts without causing
       mismerges by tests done on actual merge commits taken from Linux
       2.6 kernel development history. Additionally this can detect and
       handle merges involving renames. This is the default merge strategy
       when pulling or merging one branch.

       The recursive strategy can take the following options:

       ours
           This option forces conflicting hunks to be auto-resolved
           cleanly by favoring our version. Changes from the other tree
           that do not conflict with our side are reflected to the merge
           result. For a binary file, the entire contents are taken from
           our side.

           This should not be confused with the ours merge strategy, which
           does not even look at what the other tree contains at all. It
           discards everything the other tree did, declaring our history
           contains all that happened in it.

       theirs
           This is the opposite of ours.

       patience
           With this option, merge-recursive spends a little extra time to
           avoid mismerges that sometimes occur due to unimportant
           matching lines (e.g., braces from distinct functions). Use this
           when the branches to be merged have diverged wildly. See also
           git-diff(1) --patience.

       diff-algorithm=[patience|minimal|histogram|myers]
           Tells merge-recursive to use a different diff algorithm, which
           can help avoid mismerges that occur due to unimportant matching
           lines (such as braces from distinct functions). See also git-
           diff(1) --diff-algorithm.

       ignore-space-change, ignore-all-space, ignore-space-at-eol
           Treats lines with the indicated type of whitespace change as
           unchanged for the sake of a three-way merge. Whitespace changes
           mixed with other changes to a line are not ignored. See also
           git-diff(1) -b, -w, and --ignore-space-at-eol.

           *   If their version only introduces whitespace changes to a
               line, our version is used;

           *   If our version introduces whitespace changes but their
               version includes a substantial change, their version is
               used;

           *   Otherwise, the merge proceeds in the usual way.

       renormalize
           This runs a virtual check-out and check-in of all three stages
           of a file when resolving a three-way merge. This option is
           meant to be used when merging branches with different clean
           filters or end-of-line normalization rules. See "Merging
           branches with differing checkin/checkout attributes" in
           gitattributes(5) for details.

       no-renormalize
           Disables the renormalize option. This overrides the
           merge.renormalize configuration variable.

       no-renames
           Turn off rename detection. See also git-diff(1) --no-renames.

       find-renames[=<n>]
           Turn on rename detection, optionally setting the similarity
           threshold. This is the default. See also git-diff(1)
           --find-renames.

       rename-threshold=<n>
           Deprecated synonym for find-renames=<n>.

       subtree[=<path>]
           This option is a more advanced form of subtree strategy, where
           the strategy makes a guess on how two trees must be shifted to
           match with each other when merging. Instead, the specified path
           is prefixed (or stripped from the beginning) to make the shape
           of two trees to match.

   octopus
       This resolves cases with more than two heads, but refuses to do a
       complex merge that needs manual resolution. It is primarily meant
       to be used for bundling topic branch heads together. This is the
       default merge strategy when pulling or merging more than one
       branch.

   ours
       This resolves any number of heads, but the resulting tree of the
       merge is always that of the current branch head, effectively
       ignoring all changes from all other branches. It is meant to be
       used to supersede old development history of side branches. Note
       that this is different from the -Xours option to the recursive
       merge strategy.

   subtree
       This is a modified recursive strategy. When merging trees A and B,
       if B corresponds to a subtree of A, B is first adjusted to match
       the tree structure of A, instead of reading the trees at the same
       level. This adjustment is also done to the common ancestor tree.

   With the strategies that use 3-way merge (including the default,
   recursive), if a change is made on both branches, but later reverted on
   one of the branches, that change will be present in the merged result;
   some people find this behavior confusing. It occurs because only the
   heads and the merge base are considered when performing a merge, not
   the individual commits. The merge algorithm therefore considers the
   reverted change as no change at all, and substitutes the changed
   version instead.

DEFAULT BEHAVIOUR

   Often people use git pull without giving any parameter. Traditionally,
   this has been equivalent to saying git pull origin. However, when
   configuration branch.<name>.remote is present while on branch <name>,
   that value is used instead of origin.

   In order to determine what URL to use to fetch from, the value of the
   configuration remote.<origin>.url is consulted and if there is not any
   such variable, the value on URL: ` line in `$GIT_DIR/remotes/<origin>
   file is used.

   In order to determine what remote branches to fetch (and optionally
   store in the remote-tracking branches) when the command is run without
   any refspec parameters on the command line, values of the configuration
   variable remote.<origin>.fetch are consulted, and if there aren't any,
   $GIT_DIR/remotes/<origin> file is consulted and its `Pull: ` lines are
   used. In addition to the refspec formats described in the OPTIONS
   section, you can have a globbing refspec that looks like this:

       refs/heads/*:refs/remotes/origin/*

   A globbing refspec must have a non-empty RHS (i.e. must store what were
   fetched in remote-tracking branches), and its LHS and RHS must end with
   /*. The above specifies that all remote branches are tracked using
   remote-tracking branches in refs/remotes/origin/ hierarchy under the
   same name.

   The rule to determine which remote branch to merge after fetching is a
   bit involved, in order not to break backward compatibility.

   If explicit refspecs were given on the command line of git pull, they
   are all merged.

   When no refspec was given on the command line, then git pull uses the
   refspec from the configuration or $GIT_DIR/remotes/<origin>. In such
   cases, the following rules apply:

    1. If branch.<name>.merge configuration for the current branch <name>
       exists, that is the name of the branch at the remote site that is
       merged.

    2. If the refspec is a globbing one, nothing is merged.

    3. Otherwise the remote branch of the first refspec is merged.

EXAMPLES

   *   Update the remote-tracking branches for the repository you cloned
       from, then merge one of them into your current branch:

           $ git pull, git pull origin

       Normally the branch merged in is the HEAD of the remote repository,
       but the choice is determined by the branch.<name>.remote and
       branch.<name>.merge options; see git-config(1) for details.

   *   Merge into the current branch the remote branch next:

           $ git pull origin next

       This leaves a copy of next temporarily in FETCH_HEAD, but does not
       update any remote-tracking branches. Using remote-tracking
       branches, the same can be done by invoking fetch and merge:

           $ git fetch origin
           $ git merge origin/next

   If you tried a pull which resulted in complex conflicts and would want
   to start over, you can recover with git reset.

BUGS

   Using --recurse-submodules can only fetch new commits in already
   checked out submodules right now. When e.g. upstream added a new
   submodule in the just fetched commits of the superproject the submodule
   itself can not be fetched, making it impossible to check out that
   submodule later without having to do a fetch again. This is expected to
   be fixed in a future Git version.

SEE ALSO

   git-fetch(1), git-merge(1), git-config(1)

GIT

   Part of the git(1) suite





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The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.


Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.





Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.


Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.