6 git-format-patch - Prepare patches for e-mail submission
12 'git format-patch' [-k] [(-o|--output-directory) <dir> | --stdout]
13 [--no-thread | --thread[=<style>]]
14 [(--attach|--inline)[=<boundary>] | --no-attach]
16 [--signature=<signature> | --no-signature]
17 [--signature-file=<file>]
18 [-n | --numbered | -N | --no-numbered]
19 [--start-number <n>] [--numbered-files]
20 [--in-reply-to=<message id>] [--suffix=.<sfx>]
21 [--ignore-if-in-upstream] [--always]
22 [--cover-from-description=<mode>]
23 [--rfc] [--subject-prefix=<subject prefix>]
24 [(--reroll-count|-v) <n>]
25 [--to=<email>] [--cc=<email>]
26 [--[no-]cover-letter] [--quiet]
27 [--[no-]encode-email-headers]
28 [--no-notes | --notes[=<ref>]]
29 [--interdiff=<previous>]
30 [--range-diff=<previous> [--creation-factor=<percent>]]
31 [--filename-max-length=<n>]
33 [<common diff options>]
34 [ <since> | <revision range> ]
39 Prepare each non-merge commit with its "patch" in
40 one "message" per commit, formatted to resemble a UNIX mailbox.
41 The output of this command is convenient for e-mail submission or
42 for use with 'git am'.
44 A "message" generated by the command consists of three parts:
46 * A brief metadata header that begins with `From <commit>`
47 with a fixed `Mon Sep 17 00:00:00 2001` datestamp to help programs
48 like "file(1)" to recognize that the file is an output from this
49 command, fields that record the author identity, the author date,
50 and the title of the change (taken from the first paragraph of the
53 * The second and subsequent paragraphs of the commit log message.
55 * The "patch", which is the "diff -p --stat" output (see
56 linkgit:git-diff[1]) between the commit and its parent.
58 The log message and the patch is separated by a line with a
61 There are two ways to specify which commits to operate on.
63 1. A single commit, <since>, specifies that the commits leading
64 to the tip of the current branch that are not in the history
65 that leads to the <since> to be output.
67 2. Generic <revision range> expression (see "SPECIFYING
68 REVISIONS" section in linkgit:gitrevisions[7]) means the
69 commits in the specified range.
71 The first rule takes precedence in the case of a single <commit>. To
72 apply the second rule, i.e., format everything since the beginning of
73 history up until <commit>, use the `--root` option: `git format-patch
74 --root <commit>`. If you want to format only <commit> itself, you
75 can do this with `git format-patch -1 <commit>`.
77 By default, each output file is numbered sequentially from 1, and uses the
78 first line of the commit message (massaged for pathname safety) as
79 the filename. With the `--numbered-files` option, the output file names
80 will only be numbers, without the first line of the commit appended.
81 The names of the output files are printed to standard
82 output, unless the `--stdout` option is specified.
84 If `-o` is specified, output files are created in <dir>. Otherwise
85 they are created in the current working directory. The default path
86 can be set with the `format.outputDirectory` configuration option.
87 The `-o` option takes precedence over `format.outputDirectory`.
88 To store patches in the current working directory even when
89 `format.outputDirectory` points elsewhere, use `-o .`. All directory
90 components will be created.
92 By default, the subject of a single patch is "[PATCH] " followed by
93 the concatenation of lines from the commit message up to the first blank
94 line (see the DISCUSSION section of linkgit:git-commit[1]).
96 When multiple patches are output, the subject prefix will instead be
97 "[PATCH n/m] ". To force 1/1 to be added for a single patch, use `-n`.
98 To omit patch numbers from the subject, use `-N`.
100 If given `--thread`, `git-format-patch` will generate `In-Reply-To` and
101 `References` headers to make the second and subsequent patch mails appear
102 as replies to the first mail; this also generates a `Message-Id` header to
108 include::diff-options.txt[]
111 Prepare patches from the topmost <n> commits.
114 --output-directory <dir>::
115 Use <dir> to store the resulting files, instead of the
116 current working directory.
120 Name output in '[PATCH n/m]' format, even with a single patch.
124 Name output in '[PATCH]' format.
127 Start numbering the patches at <n> instead of 1.
130 Output file names will be a simple number sequence
131 without the default first line of the commit appended.
135 Do not strip/add '[PATCH]' from the first line of the
140 Add a `Signed-off-by` trailer to the commit message, using
141 the committer identity of yourself.
142 See the signoff option in linkgit:git-commit[1] for more information.
145 Print all commits to the standard output in mbox format,
146 instead of creating a file for each one.
148 --attach[=<boundary>]::
149 Create multipart/mixed attachment, the first part of
150 which is the commit message and the patch itself in the
151 second part, with `Content-Disposition: attachment`.
154 Disable the creation of an attachment, overriding the
155 configuration setting.
157 --inline[=<boundary>]::
158 Create multipart/mixed attachment, the first part of
159 which is the commit message and the patch itself in the
160 second part, with `Content-Disposition: inline`.
164 Controls addition of `In-Reply-To` and `References` headers to
165 make the second and subsequent mails appear as replies to the
166 first. Also controls generation of the `Message-Id` header to
169 The optional <style> argument can be either `shallow` or `deep`.
170 'shallow' threading makes every mail a reply to the head of the
171 series, where the head is chosen from the cover letter, the
172 `--in-reply-to`, and the first patch mail, in this order. 'deep'
173 threading makes every mail a reply to the previous one.
175 The default is `--no-thread`, unless the `format.thread` configuration
176 is set. If `--thread` is specified without a style, it defaults to the
177 style specified by `format.thread` if any, or else `shallow`.
179 Beware that the default for 'git send-email' is to thread emails
180 itself. If you want `git format-patch` to take care of threading, you
181 will want to ensure that threading is disabled for `git send-email`.
183 --in-reply-to=<message id>::
184 Make the first mail (or all the mails with `--no-thread`) appear as a
185 reply to the given <message id>, which avoids breaking threads to
186 provide a new patch series.
188 --ignore-if-in-upstream::
189 Do not include a patch that matches a commit in
190 <until>..<since>. This will examine all patches reachable
191 from <since> but not from <until> and compare them with the
192 patches being generated, and any patch that matches is
196 Include patches for commits that do not introduce any change,
197 which are omitted by default.
199 --cover-from-description=<mode>::
200 Controls which parts of the cover letter will be automatically
201 populated using the branch's description.
203 If `<mode>` is `message` or `default`, the cover letter subject will be
204 populated with placeholder text. The body of the cover letter will be
205 populated with the branch's description. This is the default mode when
206 no configuration nor command line option is specified.
208 If `<mode>` is `subject`, the first paragraph of the branch description will
209 populate the cover letter subject. The remainder of the description will
210 populate the body of the cover letter.
212 If `<mode>` is `auto`, if the first paragraph of the branch description
213 is greater than 100 bytes, then the mode will be `message`, otherwise
214 `subject` will be used.
216 If `<mode>` is `none`, both the cover letter subject and body will be
217 populated with placeholder text.
219 --subject-prefix=<subject prefix>::
220 Instead of the standard '[PATCH]' prefix in the subject
221 line, instead use '[<subject prefix>]'. This
222 allows for useful naming of a patch series, and can be
223 combined with the `--numbered` option.
225 --filename-max-length=<n>::
226 Instead of the standard 64 bytes, chomp the generated output
227 filenames at around '<n>' bytes (too short a value will be
228 silently raised to a reasonable length). Defaults to the
229 value of the `format.filenameMaxLength` configuration
230 variable, or 64 if unconfigured.
233 Alias for `--subject-prefix="RFC PATCH"`. RFC means "Request For
234 Comments"; use this when sending an experimental patch for
235 discussion rather than application.
239 Mark the series as the <n>-th iteration of the topic. The
240 output filenames have `v<n>` prepended to them, and the
241 subject prefix ("PATCH" by default, but configurable via the
242 `--subject-prefix` option) has ` v<n>` appended to it. E.g.
243 `--reroll-count=4` may produce `v4-0001-add-makefile.patch`
244 file that has "Subject: [PATCH v4 1/20] Add makefile" in it.
245 `<n>` does not have to be an integer (e.g. "--reroll-count=4.4",
246 or "--reroll-count=4rev2" are allowed), but the downside of
247 using such a reroll-count is that the range-diff/interdiff
248 with the previous version does not state exactly which
249 version the new interation is compared against.
252 Add a `To:` header to the email headers. This is in addition
253 to any configured headers, and may be used multiple times.
254 The negated form `--no-to` discards all `To:` headers added so
255 far (from config or command line).
258 Add a `Cc:` header to the email headers. This is in addition
259 to any configured headers, and may be used multiple times.
260 The negated form `--no-cc` discards all `Cc:` headers added so
261 far (from config or command line).
265 Use `ident` in the `From:` header of each commit email. If the
266 author ident of the commit is not textually identical to the
267 provided `ident`, place a `From:` header in the body of the
268 message with the original author. If no `ident` is given, use
271 Note that this option is only useful if you are actually sending the
272 emails and want to identify yourself as the sender, but retain the
273 original author (and `git am` will correctly pick up the in-body
274 header). Note also that `git send-email` already handles this
275 transformation for you, and this option should not be used if you are
276 feeding the result to `git send-email`.
278 --[no-]force-in-body-from::
279 With the e-mail sender specified via the `--from` option, by
280 default, an in-body "From:" to identify the real author of
281 the commit is added at the top of the commit log message if
282 the sender is different from the author. With this option,
283 the in-body "From:" is added even when the sender and the
284 author have the same name and address, which may help if the
285 mailing list software mangles the sender's identity.
286 Defaults to the value of the `format.forceInBodyFrom`
287 configuration variable.
289 --add-header=<header>::
290 Add an arbitrary header to the email headers. This is in addition
291 to any configured headers, and may be used multiple times.
292 For example, `--add-header="Organization: git-foo"`.
293 The negated form `--no-add-header` discards *all* (`To:`,
294 `Cc:`, and custom) headers added so far from config or command
297 --[no-]cover-letter::
298 In addition to the patches, generate a cover letter file
299 containing the branch description, shortlog and the overall diffstat. You can
300 fill in a description in the file before sending it out.
302 --encode-email-headers::
303 --no-encode-email-headers::
304 Encode email headers that have non-ASCII characters with
305 "Q-encoding" (described in RFC 2047), instead of outputting the
306 headers verbatim. Defaults to the value of the
307 `format.encodeEmailHeaders` configuration variable.
309 --interdiff=<previous>::
310 As a reviewer aid, insert an interdiff into the cover letter,
311 or as commentary of the lone patch of a 1-patch series, showing
312 the differences between the previous version of the patch series and
313 the series currently being formatted. `previous` is a single revision
314 naming the tip of the previous series which shares a common base with
315 the series being formatted (for example `git format-patch
316 --cover-letter --interdiff=feature/v1 -3 feature/v2`).
318 --range-diff=<previous>::
319 As a reviewer aid, insert a range-diff (see linkgit:git-range-diff[1])
320 into the cover letter, or as commentary of the lone patch of a
321 1-patch series, showing the differences between the previous
322 version of the patch series and the series currently being formatted.
323 `previous` can be a single revision naming the tip of the previous
324 series if it shares a common base with the series being formatted (for
325 example `git format-patch --cover-letter --range-diff=feature/v1 -3
326 feature/v2`), or a revision range if the two versions of the series are
327 disjoint (for example `git format-patch --cover-letter
328 --range-diff=feature/v1~3..feature/v1 -3 feature/v2`).
330 Note that diff options passed to the command affect how the primary
331 product of `format-patch` is generated, and they are not passed to
332 the underlying `range-diff` machinery used to generate the cover-letter
333 material (this may change in the future).
335 --creation-factor=<percent>::
336 Used with `--range-diff`, tweak the heuristic which matches up commits
337 between the previous and current series of patches by adjusting the
338 creation/deletion cost fudge factor. See linkgit:git-range-diff[1])
343 Append the notes (see linkgit:git-notes[1]) for the commit
344 after the three-dash line.
346 The expected use case of this is to write supporting explanation for
347 the commit that does not belong to the commit log message proper,
348 and include it with the patch submission. While one can simply write
349 these explanations after `format-patch` has run but before sending,
350 keeping them as Git notes allows them to be maintained between versions
351 of the patch series (but see the discussion of the `notes.rewrite`
352 configuration options in linkgit:git-notes[1] to use this workflow).
354 The default is `--no-notes`, unless the `format.notes` configuration is
357 --[no-]signature=<signature>::
358 Add a signature to each message produced. Per RFC 3676 the signature
359 is separated from the body by a line with '-- ' on it. If the
360 signature option is omitted the signature defaults to the Git version
363 --signature-file=<file>::
364 Works just like --signature except the signature is read from a file.
367 Instead of using `.patch` as the suffix for generated
368 filenames, use specified suffix. A common alternative is
369 `--suffix=.txt`. Leaving this empty will remove the `.patch`
372 Note that the leading character does not have to be a dot; for example,
373 you can use `--suffix=-patch` to get `0001-description-of-my-change-patch`.
377 Do not print the names of the generated files to standard output.
380 Do not output contents of changes in binary files, instead
381 display a notice that those files changed. Patches generated
382 using this option cannot be applied properly, but they are
383 still useful for code review.
386 Output an all-zero hash in each patch's From header instead
387 of the hash of the commit.
389 --[no-]base[=<commit>]::
390 Record the base tree information to identify the state the
391 patch series applies to. See the BASE TREE INFORMATION section
392 below for details. If <commit> is "auto", a base commit is
393 automatically chosen. The `--no-base` option overrides a
394 `format.useAutoBase` configuration.
397 Treat the revision argument as a <revision range>, even if it
398 is just a single commit (that would normally be treated as a
399 <since>). Note that root commits included in the specified
400 range are always formatted as creation patches, independently
404 Show progress reports on stderr as patches are generated.
408 You can specify extra mail header lines to be added to each message,
409 defaults for the subject prefix and file suffix, number patches when
410 outputting more than one patch, add "To:" or "Cc:" headers, configure
411 attachments, change the patch output directory, and sign off patches
412 with configuration variables.
416 headers = "Organization: git-foo\n"
417 subjectPrefix = CHANGE
422 attach [ = mime-boundary-string ]
424 outputDirectory = <directory>
426 coverFromDescription = auto
433 The patch produced by 'git format-patch' is in UNIX mailbox format,
434 with a fixed "magic" time stamp to indicate that the file is output
435 from format-patch rather than a real mailbox, like so:
438 From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
439 From: Tony Luck <tony.luck@intel.com>
440 Date: Tue, 13 Jul 2010 11:42:54 -0700
441 Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
442 =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig=20diet?=
444 Content-Type: text/plain; charset=UTF-8
445 Content-Transfer-Encoding: 8bit
447 arch/arm config files were slimmed down using a python script
448 (See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)
450 Do the same for ia64 so we can have sleek & trim looking
454 Typically it will be placed in a MUA's drafts folder, edited to add
455 timely commentary that should not go in the changelog after the three
456 dashes, and then sent as a message whose body, in our example, starts
457 with "arch/arm config files were...". On the receiving end, readers
458 can save interesting patches in a UNIX mailbox and apply them with
461 When a patch is part of an ongoing discussion, the patch generated by
462 'git format-patch' can be tweaked to take advantage of the 'git am
463 --scissors' feature. After your response to the discussion comes a
464 line that consists solely of "`-- >8 --`" (scissors and perforation),
465 followed by the patch with unnecessary header fields removed:
469 > So we should do such-and-such.
471 Makes sense to me. How about this patch?
474 Subject: [IA64] Put ia64 config files on the Uwe Kleine-König diet
476 arch/arm config files were slimmed down using a python script
480 When sending a patch this way, most often you are sending your own
481 patch, so in addition to the "`From $SHA1 $magic_timestamp`" marker you
482 should omit `From:` and `Date:` lines from the patch file. The patch
483 title is likely to be different from the subject of the discussion the
484 patch is in response to, so it is likely that you would want to keep
485 the Subject: line, like the example above.
487 Checking for patch corruption
488 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
489 Many mailers if not set up properly will corrupt whitespace. Here are
490 two common types of corruption:
492 * Empty context lines that do not have _any_ whitespace.
494 * Non-empty context lines that have one extra whitespace at the
497 One way to test if your MUA is set up correctly is:
499 * Send the patch to yourself, exactly the way you would, except
500 with To: and Cc: lines that do not contain the list and
503 * Save that patch to a file in UNIX mailbox format. Call it a.patch,
508 $ git fetch <project> master:test-apply
509 $ git switch test-apply
510 $ git restore --source=HEAD --staged --worktree :/
513 If it does not apply correctly, there can be various reasons.
515 * The patch itself does not apply cleanly. That is _bad_ but
516 does not have much to do with your MUA. You might want to rebase
517 the patch with linkgit:git-rebase[1] before regenerating it in
520 * The MUA corrupted your patch; "am" would complain that
521 the patch does not apply. Look in the .git/rebase-apply/ subdirectory and
522 see what 'patch' file contains and check for the common
523 corruption patterns mentioned above.
525 * While at it, check the 'info' and 'final-commit' files as well.
526 If what is in 'final-commit' is not exactly what you would want to
527 see in the commit log message, it is very likely that the
528 receiver would end up hand editing the log message when applying
529 your patch. Things like "Hi, this is my first patch.\n" in the
530 patch e-mail should come after the three-dash line that signals
531 the end of the commit message.
535 Here are some hints on how to successfully submit patches inline using
540 GMail does not have any way to turn off line wrapping in the web
541 interface, so it will mangle any emails that you send. You can however
542 use "git send-email" and send your patches through the GMail SMTP server, or
543 use any IMAP email client to connect to the google IMAP server and forward
544 the emails through that.
546 For hints on using 'git send-email' to send your patches through the
547 GMail SMTP server, see the EXAMPLE section of linkgit:git-send-email[1].
549 For hints on submission using the IMAP interface, see the EXAMPLE
550 section of linkgit:git-imap-send[1].
554 By default, Thunderbird will both wrap emails as well as flag
555 them as being 'format=flowed', both of which will make the
556 resulting email unusable by Git.
558 There are three different approaches: use an add-on to turn off line wraps,
559 configure Thunderbird to not mangle patches, or use
560 an external editor to keep Thunderbird from mangling the patches.
565 Install the Toggle Word Wrap add-on that is available from
566 https://addons.mozilla.org/thunderbird/addon/toggle-word-wrap/
567 It adds a menu entry "Enable Word Wrap" in the composer's "Options" menu
568 that you can tick off. Now you can compose the message as you otherwise do
569 (cut + paste, 'git format-patch' | 'git imap-send', etc), but you have to
570 insert line breaks manually in any text that you type.
572 Approach #2 (configuration)
573 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
576 1. Configure your mail server composition as plain text:
577 Edit...Account Settings...Composition & Addressing,
578 uncheck "Compose Messages in HTML".
580 2. Configure your general composition window to not wrap.
583 Edit..Preferences..Composition, wrap plain text messages at 0
586 Edit..Preferences..Advanced..Config Editor. Search for
587 "mail.wrap_long_lines".
588 Toggle it to make sure it is set to `false`. Also, search for
589 "mailnews.wraplength" and set the value to 0.
591 3. Disable the use of format=flowed:
592 Edit..Preferences..Advanced..Config Editor. Search for
593 "mailnews.send_plaintext_flowed".
594 Toggle it to make sure it is set to `false`.
596 After that is done, you should be able to compose email as you
597 otherwise would (cut + paste, 'git format-patch' | 'git imap-send', etc),
598 and the patches will not be mangled.
600 Approach #3 (external editor)
601 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
603 The following Thunderbird extensions are needed:
604 AboutConfig from http://aboutconfig.mozdev.org/ and
605 External Editor from http://globs.org/articles.php?lng=en&pg=8
607 1. Prepare the patch as a text file using your method of choice.
609 2. Before opening a compose window, use Edit->Account Settings to
610 uncheck the "Compose messages in HTML format" setting in the
611 "Composition & Addressing" panel of the account to be used to
614 3. In the main Thunderbird window, 'before' you open the compose
615 window for the patch, use Tools->about:config to set the
616 following to the indicated values:
619 mailnews.send_plaintext_flowed => false
620 mailnews.wraplength => 0
623 4. Open a compose window and click the external editor icon.
625 5. In the external editor window, read in the patch file and exit
628 Side note: it may be possible to do step 2 with
629 about:config and the following settings but no one's tried yet.
632 mail.html_compose => false
633 mail.identity.default.compose_html => false
634 mail.identity.id?.compose_html => false
637 There is a script in contrib/thunderbird-patch-inline which can help
638 you include patches with Thunderbird in an easy way. To use it, do the
639 steps above and then use the script as the external editor.
643 This should help you to submit patches inline using KMail.
645 1. Prepare the patch as a text file.
647 2. Click on New Mail.
649 3. Go under "Options" in the Composer window and be sure that
650 "Word wrap" is not set.
652 4. Use Message -> Insert file... and insert the patch.
654 5. Back in the compose window: add whatever other text you wish to the
655 message, complete the addressing and subject fields, and press send.
657 BASE TREE INFORMATION
658 ---------------------
660 The base tree information block is used for maintainers or third party
661 testers to know the exact state the patch series applies to. It consists
662 of the 'base commit', which is a well-known commit that is part of the
663 stable part of the project history everybody else works off of, and zero
664 or more 'prerequisite patches', which are well-known patches in flight
665 that is not yet part of the 'base commit' that need to be applied on top
666 of 'base commit' in topological order before the patches can be applied.
668 The 'base commit' is shown as "base-commit: " followed by the 40-hex of
669 the commit object name. A 'prerequisite patch' is shown as
670 "prerequisite-patch-id: " followed by the 40-hex 'patch id', which can
671 be obtained by passing the patch through the `git patch-id --stable`
674 Imagine that on top of the public commit P, you applied well-known
675 patches X, Y and Z from somebody else, and then built your three-patch
676 series A, B, C, the history would be like:
678 ................................................
679 ---P---X---Y---Z---A---B---C
680 ................................................
682 With `git format-patch --base=P -3 C` (or variants thereof, e.g. with
683 `--cover-letter` or using `Z..C` instead of `-3 C` to specify the
684 range), the base tree information block is shown at the end of the
685 first message the command outputs (either the first patch, or the
686 cover letter), like this:
690 prerequisite-patch-id: X
691 prerequisite-patch-id: Y
692 prerequisite-patch-id: Z
695 For non-linear topology, such as
697 ................................................
701 ................................................
703 You can also use `git format-patch --base=P -3 C` to generate patches
704 for A, B and C, and the identifiers for P, X, Y, Z are appended at the
705 end of the first message.
707 If set `--base=auto` in cmdline, it will automatically compute
708 the base commit as the merge base of tip commit of the remote-tracking
709 branch and revision-range specified in cmdline.
710 For a local branch, you need to make it to track a remote branch by `git branch
711 --set-upstream-to` before using this option.
716 * Extract commits between revisions R1 and R2, and apply them on top of
717 the current branch using 'git am' to cherry-pick them:
720 $ git format-patch -k --stdout R1..R2 | git am -3 -k
723 * Extract all commits which are in the current branch but not in the
727 $ git format-patch origin
730 For each commit a separate file is created in the current directory.
732 * Extract all commits that lead to 'origin' since the inception of the
736 $ git format-patch --root origin
739 * The same as the previous one:
742 $ git format-patch -M -B origin
745 Additionally, it detects and handles renames and complete rewrites
746 intelligently to produce a renaming patch. A renaming patch reduces
747 the amount of text output, and generally makes it easier to review.
748 Note that non-Git "patch" programs won't understand renaming patches, so
749 use it only when you know the recipient uses Git to apply your patch.
751 * Extract three topmost commits from the current branch and format them
752 as e-mailable patches:
755 $ git format-patch -3
761 Note that `format-patch` will omit merge commits from the output, even
762 if they are part of the requested range. A simple "patch" does not
763 include enough information for the receiving end to reproduce the same
768 linkgit:git-am[1], linkgit:git-send-email[1]
772 Part of the linkgit:git[1] suite