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GIT-FORMAT-PATCH(1)                              Git Manual                              GIT-FORMAT-PATCH(1)

       git-format-patch - Prepare patches for e-mail submission

       git format-patch [-k] [(-o|--output-directory) <dir> | --stdout]
                          [--no-thread | --thread[=<style>]]
                          [(--attach|--inline)[=<boundary>] | --no-attach]
                          [-s | --signoff]
                          [--signature=<signature> | --no-signature]
                          [-n | --numbered | -N | --no-numbered]
                          [--start-number <n>] [--numbered-files]
                          [--in-reply-to=Message-Id] [--suffix=.<sfx>]
                          [--subject-prefix=Subject-Prefix] [(--reroll-count|-v) <n>]
                          [--to=<email>] [--cc=<email>]
                          [--[no-]cover-letter] [--quiet] [--notes[=<ref>]]
                          [<common diff options>]
                          [ <since> | <revision range> ]

       Prepare each commit with its patch in one file per commit, formatted to resemble UNIX mailbox format.
       The output of this command is convenient for e-mail submission or for use with git am.

       There are two ways to specify which commits to operate on.

        1. A single commit, <since>, specifies that the commits leading to the tip of the current branch
           that are not in the history that leads to the <since> to be output.

        2. Generic <revision range> expression (see "SPECIFYING REVISIONS" section in gitrevisions(7)) means
           the commits in the specified range.

       The first rule takes precedence in the case of a single <commit>. To apply the second rule, i.e.,
       format everything since the beginning of history up until <commit>, use the --root option: git
       format-patch --root <commit>. If you want to format only <commit> itself, you can do this with git
       format-patch -1 <commit>.

       By default, each output file is numbered sequentially from 1, and uses the first line of the commit
       message (massaged for pathname safety) as the filename. With the --numbered-files option, the output
       file names will only be numbers, without the first line of the commit appended. The names of the
       output files are printed to standard output, unless the --stdout option is specified.

       If -o is specified, output files are created in <dir>. Otherwise they are created in the current
       working directory.

       By default, the subject of a single patch is "[PATCH] " followed by the concatenation of lines from
       the commit message up to the first blank line (see the DISCUSSION section of git-commit(1)).

       When multiple patches are output, the subject prefix will instead be "[PATCH n/m] ". To force 1/1 to
       be added for a single patch, use -n. To omit patch numbers from the subject, use -N.

       If given --thread, git-format-patch will generate In-Reply-To and References headers to make the
       second and subsequent patch mails appear as replies to the first mail; this also generates a
       Message-Id header to reference.

       -p, --no-stat
           Generate plain patches without any diffstats.

       -U<n>, --unified=<n>
           Generate diffs with <n> lines of context instead of the usual three.

           Spend extra time to make sure the smallest possible diff is produced.

           Generate a diff using the "patience diff" algorithm.

           Generate a diff using the "histogram diff" algorithm.

           Choose a diff algorithm. The variants are as follows:

           default, myers
               The basic greedy diff algorithm. Currently, this is the default.

               Spend extra time to make sure the smallest possible diff is produced.

               Use "patience diff" algorithm when generating patches.

               This algorithm extends the patience algorithm to "support low-occurrence common elements".

           For instance, if you configured diff.algorithm variable to a non-default value and want to use
           the default one, then you have to use --diff-algorithm=default option.

           Generate a diffstat. By default, as much space as necessary will be used for the filename part,
           and the rest for the graph part. Maximum width defaults to terminal width, or 80 columns if not
           connected to a terminal, and can be overridden by <width>. The width of the filename part can be
           limited by giving another width <name-width> after a comma. The width of the graph part can be
           limited by using --stat-graph-width=<width> (affects all commands generating a stat graph) or by
           setting diff.statGraphWidth=<width> (does not affect git format-patch). By giving a third
           parameter <count>, you can limit the output to the first <count> lines, followed by ...  if there
           are more.

           These parameters can also be set individually with --stat-width=<width>,
           --stat-name-width=<name-width> and --stat-count=<count>.

           Similar to --stat, but shows number of added and deleted lines in decimal notation and pathname
           without abbreviation, to make it more machine friendly. For binary files, outputs two - instead
           of saying 0 0.

           Output only the last line of the --stat format containing total number of modified files, as well
           as number of added and deleted lines.

           Output the distribution of relative amount of changes for each sub-directory. The behavior of
           --dirstat can be customized by passing it a comma separated list of parameters. The defaults are
           controlled by the diff.dirstat configuration variable (see git-config(1)). The following
           parameters are available:

               Compute the dirstat numbers by counting the lines that have been removed from the source, or
               added to the destination. This ignores the amount of pure code movements within a file. In
               other words, rearranging lines in a file is not counted as much as other changes. This is the
               default behavior when no parameter is given.

               Compute the dirstat numbers by doing the regular line-based diff analysis, and summing the
               removed/added line counts. (For binary files, count 64-byte chunks instead, since binary
               files have no natural concept of lines). This is a more expensive --dirstat behavior than the
               changes behavior, but it does count rearranged lines within a file as much as other changes.
               The resulting output is consistent with what you get from the other --*stat options.

               Compute the dirstat numbers by counting the number of files changed. Each changed file counts
               equally in the dirstat analysis. This is the computationally cheapest --dirstat behavior,
               since it does not have to look at the file contents at all.

               Count changes in a child directory for the parent directory as well. Note that when using
               cumulative, the sum of the percentages reported may exceed 100%. The default (non-cumulative)
               behavior can be specified with the noncumulative parameter.

               An integer parameter specifies a cut-off percent (3% by default). Directories contributing
               less than this percentage of the changes are not shown in the output.

           Example: The following will count changed files, while ignoring directories with less than 10% of
           the total amount of changed files, and accumulating child directory counts in the parent
           directories: --dirstat=files,10,cumulative.

           Output a condensed summary of extended header information such as creations, renames and mode

           Turn off rename detection, even when the configuration file gives the default to do so.

           Instead of the first handful of characters, show the full pre- and post-image blob object names
           on the "index" line when generating patch format output.

           In addition to --full-index, output a binary diff that can be applied with git-apply.

           Instead of showing the full 40-byte hexadecimal object name in diff-raw format output and
           diff-tree header lines, show only a partial prefix. This is independent of the --full-index
           option above, which controls the diff-patch output format. Non default number of digits can be
           specified with --abbrev=<n>.

       -B[<n>][/<m>], --break-rewrites[=[<n>][/<m>]]
           Break complete rewrite changes into pairs of delete and create. This serves two purposes:

           It affects the way a change that amounts to a total rewrite of a file not as a series of deletion
           and insertion mixed together with a very few lines that happen to match textually as the context,
           but as a single deletion of everything old followed by a single insertion of everything new, and
           the number m controls this aspect of the -B option (defaults to 60%).  -B/70% specifies that less
           than 30% of the original should remain in the result for Git to consider it a total rewrite (i.e.
           otherwise the resulting patch will be a series of deletion and insertion mixed together with
           context lines).

           When used with -M, a totally-rewritten file is also considered as the source of a rename (usually
           -M only considers a file that disappeared as the source of a rename), and the number n controls
           this aspect of the -B option (defaults to 50%).  -B20% specifies that a change with addition and
           deletion compared to 20% or more of the file's size are eligible for being picked up as a
           possible source of a rename to another file.

       -M[<n>], --find-renames[=<n>]
           Detect renames. If n is specified, it is a threshold on the similarity index (i.e. amount of
           addition/deletions compared to the file's size). For example, -M90% means Git should consider a
           delete/add pair to be a rename if more than 90% of the file hasn't changed. Without a % sign, the
           number is to be read as a fraction, with a decimal point before it. I.e., -M5 becomes 0.5, and is
           thus the same as -M50%. Similarly, -M05 is the same as -M5%. To limit detection to exact renames,
           use -M100%.

       -C[<n>], --find-copies[=<n>]
           Detect copies as well as renames. See also --find-copies-harder. If n is specified, it has the
           same meaning as for -M<n>.

           For performance reasons, by default, -C option finds copies only if the original file of the copy
           was modified in the same changeset. This flag makes the command inspect unmodified files as
           candidates for the source of copy. This is a very expensive operation for large projects, so use
           it with caution. Giving more than one -C option has the same effect.

       -D, --irreversible-delete
           Omit the preimage for deletes, i.e. print only the header but not the diff between the preimage
           and /dev/null. The resulting patch is not meant to be applied with patch nor git apply; this is
           solely for people who want to just concentrate on reviewing the text after the change. In
           addition, the output obviously lack enough information to apply such a patch in reverse, even
           manually, hence the name of the option.

           When used together with -B, omit also the preimage in the deletion part of a delete/create pair.

           The -M and -C options require O(n^2) processing time where n is the number of potential
           rename/copy targets. This option prevents rename/copy detection from running if the number of
           rename/copy targets exceeds the specified number.

           Output the patch in the order specified in the <orderfile>, which has one shell glob pattern per

       -a, --text
           Treat all files as text.

           Ignore changes in whitespace at EOL.

       -b, --ignore-space-change
           Ignore changes in amount of whitespace. This ignores whitespace at line end, and considers all
           other sequences of one or more whitespace characters to be equivalent.

       -w, --ignore-all-space
           Ignore whitespace when comparing lines. This ignores differences even if one line has whitespace
           where the other line has none.

           Show the context between diff hunks, up to the specified number of lines, thereby fusing hunks
           that are close to each other.

       -W, --function-context
           Show whole surrounding functions of changes.

           Allow an external diff helper to be executed. If you set an external diff driver with
           gitattributes(5), you need to use this option with git-log(1) and friends.

           Disallow external diff drivers.

       --textconv, --no-textconv
           Allow (or disallow) external text conversion filters to be run when comparing binary files. See
           gitattributes(5) for details. Because textconv filters are typically a one-way conversion, the
           resulting diff is suitable for human consumption, but cannot be applied. For this reason,
           textconv filters are enabled by default only for git-diff(1) and git-log(1), but not for git-format-patch(1) gitformat-patch(1)
           format-patch(1) or diff plumbing commands.

           Ignore changes to submodules in the diff generation. <when> can be either "none", "untracked",
           "dirty" or "all", which is the default Using "none" will consider the submodule modified when it
           either contains untracked or modified files or its HEAD differs from the commit recorded in the
           superproject and can be used to override any settings of the ignore option in git-config(1) or
           gitmodules(5). When "untracked" is used submodules are not considered dirty when they only
           contain untracked content (but they are still scanned for modified content). Using "dirty"
           ignores all changes to the work tree of submodules, only changes to the commits stored in the
           superproject are shown (this was the behavior until 1.7.0). Using "all" hides all changes to

           Show the given source prefix instead of "a/".

           Show the given destination prefix instead of "b/".

           Do not show any source or destination prefix.

       For more detailed explanation on these common options, see also gitdiffcore(7).

           Prepare patches from the topmost <n> commits.

       -o <dir>, --output-directory <dir>
           Use <dir> to store the resulting files, instead of the current working directory.

       -n, --numbered
           Name output in [PATCH n/m] format, even with a single patch.

       -N, --no-numbered
           Name output in [PATCH] format.

       --start-number <n>
           Start numbering the patches at <n> instead of 1.

           Output file names will be a simple number sequence without the default first line of the commit

       -k, --keep-subject
           Do not strip/add [PATCH] from the first line of the commit log message.

       -s, --signoff
           Add Signed-off-by: line to the commit message, using the committer identity of yourself.

           Print all commits to the standard output in mbox format, instead of creating a file for each one.

           Create multipart/mixed attachment, the first part of which is the commit message and the patch
           itself in the second part, with Content-Disposition: attachment.

           Disable the creation of an attachment, overriding the configuration setting.

           Create multipart/mixed attachment, the first part of which is the commit message and the patch
           itself in the second part, with Content-Disposition: inline.

       --thread[=<style>], --no-thread
           Controls addition of In-Reply-To and References headers to make the second and subsequent mails
           appear as replies to the first. Also controls generation of the Message-Id header to reference.

           The optional <style> argument can be either shallow or deep.  shallow threading makes every mail
           a reply to the head of the series, where the head is chosen from the cover letter, the
           --in-reply-to, and the first patch mail, in this order.  deep threading makes every mail a reply
           to the previous one.

           The default is --no-thread, unless the format.thread configuration is set. If --thread is
           specified without a style, it defaults to the style specified by format.thread if any, or else

           Beware that the default for git send-email is to thread emails itself. If you want git
           format-patch to take care of threading, you will want to ensure that threading is disabled for
           git send-email.

           Make the first mail (or all the mails with --no-thread) appear as a reply to the given
           Message-Id, which avoids breaking threads to provide a new patch series.

           Do not include a patch that matches a commit in <until>..<since>. This will examine all patches
           reachable from <since> but not from <until> and compare them with the patches being generated,
           and any patch that matches is ignored.

           Instead of the standard [PATCH] prefix in the subject line, instead use [<Subject-Prefix>]. This
           allows for useful naming of a patch series, and can be combined with the --numbered option.

       -v <n>, --reroll-count=<n>
           Mark the series as the <n>-th iteration of the topic. The output filenames have v<n> pretended to
           them, and the subject prefix ("PATCH" by default, but configurable via the --subject-prefix
           option) has ` v<n>` appended to it. E.g.  --reroll-count=4 may produce v4-0001-add-makefile.patch
           file that has "Subject: [PATCH v4 1/20] Add makefile" in it.

           Add a To: header to the email headers. This is in addition to any configured headers, and may be
           used multiple times. The negated form --no-to discards all To: headers added so far (from config
           or command line).

           Add a Cc: header to the email headers. This is in addition to any configured headers, and may be
           used multiple times. The negated form --no-cc discards all Cc: headers added so far (from config
           or command line).

           Add an arbitrary header to the email headers. This is in addition to any configured headers, and
           may be used multiple times. For example, --add-header="Organization: git-foo". The negated form
           --no-add-header discards all (To:, Cc:, and custom) headers added so far from config or command

           In addition to the patches, generate a cover letter file containing the shortlog and the overall
           diffstat. You can fill in a description in the file before sending it out.

           Append the notes (see git-notes(1)) for the commit after the three-dash line.

           The expected use case of this is to write supporting explanation for the commit that does not
           belong to the commit log message proper, and include it with the patch submission. While one can
           simply write these explanations after format-patch has run but before sending, keeping them as
           Git notes allows them to be maintained between versions of the patch series (but see the
           discussion of the notes.rewrite configuration options in git-notes(1) to use this workflow).

           Add a signature to each message produced. Per RFC 3676 the signature is separated from the body
           by a line with '-- ' on it. If the signature option is omitted the signature defaults to the Git
           version number.

           Instead of using .patch as the suffix for generated filenames, use specified suffix. A common
           alternative is --suffix=.txt. Leaving this empty will remove the .patch suffix.

           Note that the leading character does not have to be a dot; for example, you can use
           --suffix=-patch to get 0001-description-of-my-change-patch.

           Do not print the names of the generated files to standard output.

           Do not output contents of changes in binary files, instead display a notice that those files
           changed. Patches generated using this option cannot be applied properly, but they are still
           useful for code review.

           Treat the revision argument as a <revision range>, even if it is just a single commit (that would
           normally be treated as a <since>). Note that root commits included in the specified range are
           always formatted as creation patches, independently of this flag.

       You can specify extra mail header lines to be added to each message, defaults for the subject prefix
       and file suffix, number patches when outputting more than one patch, add "To" or "Cc:" headers,
       configure attachments, and sign off patches with configuration variables.

                   headers = "Organization: git-foo\n"
                   subjectprefix = CHANGE
                   suffix = .txt
                   numbered = auto
                   to = <email>
                   cc = <email>
                   attach [ = mime-boundary-string ]
                   signoff = true
                   coverletter = auto

       The patch produced by git format-patch is in UNIX mailbox format, with a fixed "magic" time stamp to
       indicate that the file is output from format-patch rather than a real mailbox, like so:

           From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
           From: Tony Luck <>
           Date: Tue, 13 Jul 2010 11:42:54 -0700
           Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
           MIME-Version: 1.0
           Content-Type: text/plain; charset=UTF-8
           Content-Transfer-Encoding: 8bit

           arch/arm config files were slimmed down using a python script
           (See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)

           Do the same for ia64 so we can have sleek & trim looking

       Typically it will be placed in a MUA's drafts folder, edited to add timely commentary that should not
       go in the changelog after the three dashes, and then sent as a message whose body, in our example,
       starts with "arch/arm config files were...". On the receiving end, readers can save interesting
       patches in a UNIX mailbox and apply them with git-am(1).

       When a patch is part of an ongoing discussion, the patch generated by git format-patch can be tweaked
       to take advantage of the git am --scissors feature. After your response to the discussion comes a
       line that consists solely of "-- >8 --" (scissors and perforation), followed by the patch with
       unnecessary header fields removed:

           > So we should do such-and-such.

           Makes sense to me.  How about this patch?

           -- >8 --Subject: -Subject:
           Subject: [IA64] Put ia64 config files on the Uwe Kleine-K"nig diet

           arch/arm config files were slimmed down using a python script

       When sending a patch this way, most often you are sending your own patch, so in addition to the "From
       $SHA1 $magic_timestamp" marker you should omit From: and Date: lines from the patch file. The patch
       title is likely to be different from the subject of the discussion the patch is in response to, so it
       is likely that you would want to keep the Subject: line, like the example above.

   Checking for patch corruption
       Many mailers if not set up properly will corrupt whitespace. Here are two common types of corruption:

          Empty context lines that do not have any whitespace.

          Non-empty context lines that have one extra whitespace at the beginning.

       One way to test if your MUA is set up correctly is:

          Send the patch to yourself, exactly the way you would, except with To: and Cc: lines that do not
           contain the list and maintainer address.

          Save that patch to a file in UNIX mailbox format. Call it a.patch, say.

          Apply it:

               $ git fetch <project> master:test-apply
               $ git checkout test-apply
               $ git reset --hard
               $ git am a.patch

       If it does not apply correctly, there can be various reasons.

          The patch itself does not apply cleanly. That is bad but does not have much to do with your MUA.
           You might want to rebase the patch with git-rebase(1) before regenerating it in this case.

          The MUA corrupted your patch; "am" would complain that the patch does not apply. Look in the
           .git/rebase-apply/ subdirectory and see what patch file contains and check for the common
           corruption patterns mentioned above.

          While at it, check the info and final-commit files as well. If what is in final-commit is not
           exactly what you would want to see in the commit log message, it is very likely that the receiver
           would end up hand editing the log message when applying your patch. Things like "Hi, this is my
           first patch.\n" in the patch e-mail should come after the three-dash line that signals the end of
           the commit message.

       Here are some hints on how to successfully submit patches inline using various mailers.

       GMail does not have any way to turn off line wrapping in the web interface, so it will mangle any
       emails that you send. You can however use "git send-email" and send your patches through the GMail
       SMTP server, or use any IMAP email client to connect to the google IMAP server and forward the emails
       through that.

       For hints on using git send-email to send your patches through the GMail SMTP server, see the EXAMPLE
       section of git-send-email(1).

       For hints on submission using the IMAP interface, see the EXAMPLE section of git-imap-send(1).

       By default, Thunderbird will both wrap emails as well as flag them as being format=flowed, both of
       which will make the resulting email unusable by Git.

       There are three different approaches: use an add-on to turn off line wraps, configure Thunderbird to
       not mangle patches, or use an external editor to keep Thunderbird from mangling the patches.

       Approach #1 (add-on)
           Install the Toggle Word Wrap add-on that is available from
  It adds a menu entry "Enable Word
           Wrap" in the composer's "Options" menu that you can tick off. Now you can compose the message as
           you otherwise do (cut + paste, git format-patch | git imap-send, etc), but you have to insert
           line breaks manually in any text that you type.

       Approach #2 (configuration)
           Three steps:

            1. Configure your mail server composition as plain text: Edit...Account Settings...Composition &
               Addressing, uncheck "Compose Messages in HTML".

            2. Configure your general composition window to not wrap.

               In Thunderbird 2: Edit..Preferences..Composition, wrap plain text messages at 0

               In Thunderbird 3: Edit..Preferences..Advanced..Config Editor. Search for
               "mail.wrap_long_lines". Toggle it to make sure it is set to false.

            3. Disable the use of format=flowed: Edit..Preferences..Advanced..Config Editor. Search for
               "mailnews.send_plaintext_flowed". Toggle it to make sure it is set to false.

           After that is done, you should be able to compose email as you otherwise would (cut + paste, git
           format-patch | git imap-send, etc), and the patches will not be mangled.

       Approach #3 (external editor)
           The following Thunderbird extensions are needed: AboutConfig from
           and External Editor from

            1. Prepare the patch as a text file using your method of choice.

            2. Before opening a compose window, use Edit->Account Settings to uncheck the "Compose messages
               in HTML format" setting in the "Composition & Addressing" panel of the account to be used to
               send the patch.

            3. In the main Thunderbird window, before you open the compose window for the patch, use
               Tools->about:config to set the following to the indicated values:

                           mailnews.send_plaintext_flowed  => false
                           mailnews.wraplength             => 0

            4. Open a compose window and click the external editor icon.

            5. In the external editor window, read in the patch file and exit the editor normally.

           Side note: it may be possible to do step 2 with about:config and the following settings but no
           one's tried yet.

                       mail.html_compose                       => false
                       mail.identity.default.compose_html      => false
                       => false

           There is a script in contrib/thunderbird-patch-inline which can help you include patches with
           Thunderbird in an easy way. To use it, do the steps above and then use the script as the external

       This should help you to submit patches inline using KMail.

        1. Prepare the patch as a text file.

        2. Click on New Mail.

        3. Go under "Options" in the Composer window and be sure that "Word wrap" is not set.

        4. Use Message -> Insert file... and insert the patch.

        5. Back in the compose window: add whatever other text you wish to the message, complete the
           addressing and subject fields, and press send.

          Extract commits between revisions R1 and R2, and apply them on top of the current branch using
           git am to cherry-pick them:

               $ git format-patch -k --stdout R1..R2 | git am -3 -k

          Extract all commits which are in the current branch but not in the origin branch:

               $ git format-patch origin

           For each commit a separate file is created in the current directory.

          Extract all commits that lead to origin since the inception of the project:

               $ git format-patch --root origin

          The same as the previous one:

               $ git format-patch -M -B origin

           Additionally, it detects and handles renames and complete rewrites intelligently to produce a
           renaming patch. A renaming patch reduces the amount of text output, and generally makes it easier
           to review. Note that non-Git "patch" programs won't understand renaming patches, so use it only
           when you know the recipient uses Git to apply your patch.

          Extract three topmost commits from the current branch and format them as e-mailable patches:

               $ git format-patch -3

       git-am(1), git-send-email(1)

       Part of the git(1) suite

Git 1.8.3                                        05/24/2013                              GIT-FORMAT-PATCH(1)

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