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. `--thread` without an argument is equivalent to `--thread=shallow`.
178 Beware that the default for 'git send-email' is to thread emails
179 itself. If you want `git format-patch` to take care of threading, you
180 will want to ensure that threading is disabled for `git send-email`.
182 --in-reply-to=<message id>::
183 Make the first mail (or all the mails with `--no-thread`) appear as a
184 reply to the given <message id>, which avoids breaking threads to
185 provide a new patch series.
187 --ignore-if-in-upstream::
188 Do not include a patch that matches a commit in
189 <until>..<since>. This will examine all patches reachable
190 from <since> but not from <until> and compare them with the
191 patches being generated, and any patch that matches is
195 Include patches for commits that do not introduce any change,
196 which are omitted by default.
198 --cover-from-description=<mode>::
199 Controls which parts of the cover letter will be automatically
200 populated using the branch's description.
202 If `<mode>` is `message` or `default`, the cover letter subject will be
203 populated with placeholder text. The body of the cover letter will be
204 populated with the branch's description. This is the default mode when
205 no configuration nor command line option is specified.
207 If `<mode>` is `subject`, the first paragraph of the branch description will
208 populate the cover letter subject. The remainder of the description will
209 populate the body of the cover letter.
211 If `<mode>` is `auto`, if the first paragraph of the branch description
212 is greater than 100 bytes, then the mode will be `message`, otherwise
213 `subject` will be used.
215 If `<mode>` is `none`, both the cover letter subject and body will be
216 populated with placeholder text.
218 --subject-prefix=<subject prefix>::
219 Instead of the standard '[PATCH]' prefix in the subject
220 line, instead use '[<subject prefix>]'. This
221 allows for useful naming of a patch series, and can be
222 combined with the `--numbered` option.
224 --filename-max-length=<n>::
225 Instead of the standard 64 bytes, chomp the generated output
226 filenames at around '<n>' bytes (too short a value will be
227 silently raised to a reasonable length). Defaults to the
228 value of the `format.filenameMaxLength` configuration
229 variable, or 64 if unconfigured.
232 Alias for `--subject-prefix="RFC PATCH"`. RFC means "Request For
233 Comments"; use this when sending an experimental patch for
234 discussion rather than application.
238 Mark the series as the <n>-th iteration of the topic. The
239 output filenames have `v<n>` prepended to them, and the
240 subject prefix ("PATCH" by default, but configurable via the
241 `--subject-prefix` option) has ` v<n>` appended to it. E.g.
242 `--reroll-count=4` may produce `v4-0001-add-makefile.patch`
243 file that has "Subject: [PATCH v4 1/20] Add makefile" in it.
244 `<n>` does not have to be an integer (e.g. "--reroll-count=4.4",
245 or "--reroll-count=4rev2" are allowed), but the downside of
246 using such a reroll-count is that the range-diff/interdiff
247 with the previous version does not state exactly which
248 version the new interation is compared against.
251 Add a `To:` header to the email headers. This is in addition
252 to any configured headers, and may be used multiple times.
253 The negated form `--no-to` discards all `To:` headers added so
254 far (from config or command line).
257 Add a `Cc:` header to the email headers. This is in addition
258 to any configured headers, and may be used multiple times.
259 The negated form `--no-cc` discards all `Cc:` headers added so
260 far (from config or command line).
264 Use `ident` in the `From:` header of each commit email. If the
265 author ident of the commit is not textually identical to the
266 provided `ident`, place a `From:` header in the body of the
267 message with the original author. If no `ident` is given, use
270 Note that this option is only useful if you are actually sending the
271 emails and want to identify yourself as the sender, but retain the
272 original author (and `git am` will correctly pick up the in-body
273 header). Note also that `git send-email` already handles this
274 transformation for you, and this option should not be used if you are
275 feeding the result to `git send-email`.
277 --[no-]force-in-body-from::
278 With the e-mail sender specified via the `--from` option, by
279 default, an in-body "From:" to identify the real author of
280 the commit is added at the top of the commit log message if
281 the sender is different from the author. With this option,
282 the in-body "From:" is added even when the sender and the
283 author have the same name and address, which may help if the
284 mailing list software mangles the sender's identity.
285 Defaults to the value of the `format.forceInBodyFrom`
286 configuration variable.
288 --add-header=<header>::
289 Add an arbitrary header to the email headers. This is in addition
290 to any configured headers, and may be used multiple times.
291 For example, `--add-header="Organization: git-foo"`.
292 The negated form `--no-add-header` discards *all* (`To:`,
293 `Cc:`, and custom) headers added so far from config or command
296 --[no-]cover-letter::
297 In addition to the patches, generate a cover letter file
298 containing the branch description, shortlog and the overall diffstat. You can
299 fill in a description in the file before sending it out.
301 --encode-email-headers::
302 --no-encode-email-headers::
303 Encode email headers that have non-ASCII characters with
304 "Q-encoding" (described in RFC 2047), instead of outputting the
305 headers verbatim. Defaults to the value of the
306 `format.encodeEmailHeaders` configuration variable.
308 --interdiff=<previous>::
309 As a reviewer aid, insert an interdiff into the cover letter,
310 or as commentary of the lone patch of a 1-patch series, showing
311 the differences between the previous version of the patch series and
312 the series currently being formatted. `previous` is a single revision
313 naming the tip of the previous series which shares a common base with
314 the series being formatted (for example `git format-patch
315 --cover-letter --interdiff=feature/v1 -3 feature/v2`).
317 --range-diff=<previous>::
318 As a reviewer aid, insert a range-diff (see linkgit:git-range-diff[1])
319 into the cover letter, or as commentary of the lone patch of a
320 1-patch series, showing the differences between the previous
321 version of the patch series and the series currently being formatted.
322 `previous` can be a single revision naming the tip of the previous
323 series if it shares a common base with the series being formatted (for
324 example `git format-patch --cover-letter --range-diff=feature/v1 -3
325 feature/v2`), or a revision range if the two versions of the series are
326 disjoint (for example `git format-patch --cover-letter
327 --range-diff=feature/v1~3..feature/v1 -3 feature/v2`).
329 Note that diff options passed to the command affect how the primary
330 product of `format-patch` is generated, and they are not passed to
331 the underlying `range-diff` machinery used to generate the cover-letter
332 material (this may change in the future).
334 --creation-factor=<percent>::
335 Used with `--range-diff`, tweak the heuristic which matches up commits
336 between the previous and current series of patches by adjusting the
337 creation/deletion cost fudge factor. See linkgit:git-range-diff[1])
342 Append the notes (see linkgit:git-notes[1]) for the commit
343 after the three-dash line.
345 The expected use case of this is to write supporting explanation for
346 the commit that does not belong to the commit log message proper,
347 and include it with the patch submission. While one can simply write
348 these explanations after `format-patch` has run but before sending,
349 keeping them as Git notes allows them to be maintained between versions
350 of the patch series (but see the discussion of the `notes.rewrite`
351 configuration options in linkgit:git-notes[1] to use this workflow).
353 The default is `--no-notes`, unless the `format.notes` configuration is
356 --[no-]signature=<signature>::
357 Add a signature to each message produced. Per RFC 3676 the signature
358 is separated from the body by a line with '-- ' on it. If the
359 signature option is omitted the signature defaults to the Git version
362 --signature-file=<file>::
363 Works just like --signature except the signature is read from a file.
366 Instead of using `.patch` as the suffix for generated
367 filenames, use specified suffix. A common alternative is
368 `--suffix=.txt`. Leaving this empty will remove the `.patch`
371 Note that the leading character does not have to be a dot; for example,
372 you can use `--suffix=-patch` to get `0001-description-of-my-change-patch`.
376 Do not print the names of the generated files to standard output.
379 Do not output contents of changes in binary files, instead
380 display a notice that those files changed. Patches generated
381 using this option cannot be applied properly, but they are
382 still useful for code review.
385 Output an all-zero hash in each patch's From header instead
386 of the hash of the commit.
388 --[no-]base[=<commit>]::
389 Record the base tree information to identify the state the
390 patch series applies to. See the BASE TREE INFORMATION section
391 below for details. If <commit> is "auto", a base commit is
392 automatically chosen. The `--no-base` option overrides a
393 `format.useAutoBase` configuration.
396 Treat the revision argument as a <revision range>, even if it
397 is just a single commit (that would normally be treated as a
398 <since>). Note that root commits included in the specified
399 range are always formatted as creation patches, independently
403 Show progress reports on stderr as patches are generated.
407 You can specify extra mail header lines to be added to each message,
408 defaults for the subject prefix and file suffix, number patches when
409 outputting more than one patch, add "To:" or "Cc:" headers, configure
410 attachments, change the patch output directory, and sign off patches
411 with configuration variables.
415 headers = "Organization: git-foo\n"
416 subjectPrefix = CHANGE
421 attach [ = mime-boundary-string ]
423 outputDirectory = <directory>
425 coverFromDescription = auto
432 The patch produced by 'git format-patch' is in UNIX mailbox format,
433 with a fixed "magic" time stamp to indicate that the file is output
434 from format-patch rather than a real mailbox, like so:
437 From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
438 From: Tony Luck <tony.luck@intel.com>
439 Date: Tue, 13 Jul 2010 11:42:54 -0700
440 Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
441 =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig=20diet?=
443 Content-Type: text/plain; charset=UTF-8
444 Content-Transfer-Encoding: 8bit
446 arch/arm config files were slimmed down using a python script
447 (See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)
449 Do the same for ia64 so we can have sleek & trim looking
453 Typically it will be placed in a MUA's drafts folder, edited to add
454 timely commentary that should not go in the changelog after the three
455 dashes, and then sent as a message whose body, in our example, starts
456 with "arch/arm config files were...". On the receiving end, readers
457 can save interesting patches in a UNIX mailbox and apply them with
460 When a patch is part of an ongoing discussion, the patch generated by
461 'git format-patch' can be tweaked to take advantage of the 'git am
462 --scissors' feature. After your response to the discussion comes a
463 line that consists solely of "`-- >8 --`" (scissors and perforation),
464 followed by the patch with unnecessary header fields removed:
468 > So we should do such-and-such.
470 Makes sense to me. How about this patch?
473 Subject: [IA64] Put ia64 config files on the Uwe Kleine-König diet
475 arch/arm config files were slimmed down using a python script
479 When sending a patch this way, most often you are sending your own
480 patch, so in addition to the "`From $SHA1 $magic_timestamp`" marker you
481 should omit `From:` and `Date:` lines from the patch file. The patch
482 title is likely to be different from the subject of the discussion the
483 patch is in response to, so it is likely that you would want to keep
484 the Subject: line, like the example above.
486 Checking for patch corruption
487 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
488 Many mailers if not set up properly will corrupt whitespace. Here are
489 two common types of corruption:
491 * Empty context lines that do not have _any_ whitespace.
493 * Non-empty context lines that have one extra whitespace at the
496 One way to test if your MUA is set up correctly is:
498 * Send the patch to yourself, exactly the way you would, except
499 with To: and Cc: lines that do not contain the list and
502 * Save that patch to a file in UNIX mailbox format. Call it a.patch,
507 $ git fetch <project> master:test-apply
508 $ git switch test-apply
509 $ git restore --source=HEAD --staged --worktree :/
512 If it does not apply correctly, there can be various reasons.
514 * The patch itself does not apply cleanly. That is _bad_ but
515 does not have much to do with your MUA. You might want to rebase
516 the patch with linkgit:git-rebase[1] before regenerating it in
519 * The MUA corrupted your patch; "am" would complain that
520 the patch does not apply. Look in the .git/rebase-apply/ subdirectory and
521 see what 'patch' file contains and check for the common
522 corruption patterns mentioned above.
524 * While at it, check the 'info' and 'final-commit' files as well.
525 If what is in 'final-commit' is not exactly what you would want to
526 see in the commit log message, it is very likely that the
527 receiver would end up hand editing the log message when applying
528 your patch. Things like "Hi, this is my first patch.\n" in the
529 patch e-mail should come after the three-dash line that signals
530 the end of the commit message.
534 Here are some hints on how to successfully submit patches inline using
539 GMail does not have any way to turn off line wrapping in the web
540 interface, so it will mangle any emails that you send. You can however
541 use "git send-email" and send your patches through the GMail SMTP server, or
542 use any IMAP email client to connect to the google IMAP server and forward
543 the emails through that.
545 For hints on using 'git send-email' to send your patches through the
546 GMail SMTP server, see the EXAMPLE section of linkgit:git-send-email[1].
548 For hints on submission using the IMAP interface, see the EXAMPLE
549 section of linkgit:git-imap-send[1].
553 By default, Thunderbird will both wrap emails as well as flag
554 them as being 'format=flowed', both of which will make the
555 resulting email unusable by Git.
557 There are three different approaches: use an add-on to turn off line wraps,
558 configure Thunderbird to not mangle patches, or use
559 an external editor to keep Thunderbird from mangling the patches.
564 Install the Toggle Word Wrap add-on that is available from
565 https://addons.mozilla.org/thunderbird/addon/toggle-word-wrap/
566 It adds a menu entry "Enable Word Wrap" in the composer's "Options" menu
567 that you can tick off. Now you can compose the message as you otherwise do
568 (cut + paste, 'git format-patch' | 'git imap-send', etc), but you have to
569 insert line breaks manually in any text that you type.
571 Approach #2 (configuration)
572 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
575 1. Configure your mail server composition as plain text:
576 Edit...Account Settings...Composition & Addressing,
577 uncheck "Compose Messages in HTML".
579 2. Configure your general composition window to not wrap.
582 Edit..Preferences..Composition, wrap plain text messages at 0
585 Edit..Preferences..Advanced..Config Editor. Search for
586 "mail.wrap_long_lines".
587 Toggle it to make sure it is set to `false`. Also, search for
588 "mailnews.wraplength" and set the value to 0.
590 3. Disable the use of format=flowed:
591 Edit..Preferences..Advanced..Config Editor. Search for
592 "mailnews.send_plaintext_flowed".
593 Toggle it to make sure it is set to `false`.
595 After that is done, you should be able to compose email as you
596 otherwise would (cut + paste, 'git format-patch' | 'git imap-send', etc),
597 and the patches will not be mangled.
599 Approach #3 (external editor)
600 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
602 The following Thunderbird extensions are needed:
603 AboutConfig from http://aboutconfig.mozdev.org/ and
604 External Editor from http://globs.org/articles.php?lng=en&pg=8
606 1. Prepare the patch as a text file using your method of choice.
608 2. Before opening a compose window, use Edit->Account Settings to
609 uncheck the "Compose messages in HTML format" setting in the
610 "Composition & Addressing" panel of the account to be used to
613 3. In the main Thunderbird window, 'before' you open the compose
614 window for the patch, use Tools->about:config to set the
615 following to the indicated values:
618 mailnews.send_plaintext_flowed => false
619 mailnews.wraplength => 0
622 4. Open a compose window and click the external editor icon.
624 5. In the external editor window, read in the patch file and exit
627 Side note: it may be possible to do step 2 with
628 about:config and the following settings but no one's tried yet.
631 mail.html_compose => false
632 mail.identity.default.compose_html => false
633 mail.identity.id?.compose_html => false
636 There is a script in contrib/thunderbird-patch-inline which can help
637 you include patches with Thunderbird in an easy way. To use it, do the
638 steps above and then use the script as the external editor.
642 This should help you to submit patches inline using KMail.
644 1. Prepare the patch as a text file.
646 2. Click on New Mail.
648 3. Go under "Options" in the Composer window and be sure that
649 "Word wrap" is not set.
651 4. Use Message -> Insert file... and insert the patch.
653 5. Back in the compose window: add whatever other text you wish to the
654 message, complete the addressing and subject fields, and press send.
656 BASE TREE INFORMATION
657 ---------------------
659 The base tree information block is used for maintainers or third party
660 testers to know the exact state the patch series applies to. It consists
661 of the 'base commit', which is a well-known commit that is part of the
662 stable part of the project history everybody else works off of, and zero
663 or more 'prerequisite patches', which are well-known patches in flight
664 that is not yet part of the 'base commit' that need to be applied on top
665 of 'base commit' in topological order before the patches can be applied.
667 The 'base commit' is shown as "base-commit: " followed by the 40-hex of
668 the commit object name. A 'prerequisite patch' is shown as
669 "prerequisite-patch-id: " followed by the 40-hex 'patch id', which can
670 be obtained by passing the patch through the `git patch-id --stable`
673 Imagine that on top of the public commit P, you applied well-known
674 patches X, Y and Z from somebody else, and then built your three-patch
675 series A, B, C, the history would be like:
677 ................................................
678 ---P---X---Y---Z---A---B---C
679 ................................................
681 With `git format-patch --base=P -3 C` (or variants thereof, e.g. with
682 `--cover-letter` or using `Z..C` instead of `-3 C` to specify the
683 range), the base tree information block is shown at the end of the
684 first message the command outputs (either the first patch, or the
685 cover letter), like this:
689 prerequisite-patch-id: X
690 prerequisite-patch-id: Y
691 prerequisite-patch-id: Z
694 For non-linear topology, such as
696 ................................................
700 ................................................
702 You can also use `git format-patch --base=P -3 C` to generate patches
703 for A, B and C, and the identifiers for P, X, Y, Z are appended at the
704 end of the first message.
706 If set `--base=auto` in cmdline, it will automatically compute
707 the base commit as the merge base of tip commit of the remote-tracking
708 branch and revision-range specified in cmdline.
709 For a local branch, you need to make it to track a remote branch by `git branch
710 --set-upstream-to` before using this option.
715 * Extract commits between revisions R1 and R2, and apply them on top of
716 the current branch using 'git am' to cherry-pick them:
719 $ git format-patch -k --stdout R1..R2 | git am -3 -k
722 * Extract all commits which are in the current branch but not in the
726 $ git format-patch origin
729 For each commit a separate file is created in the current directory.
731 * Extract all commits that lead to 'origin' since the inception of the
735 $ git format-patch --root origin
738 * The same as the previous one:
741 $ git format-patch -M -B origin
744 Additionally, it detects and handles renames and complete rewrites
745 intelligently to produce a renaming patch. A renaming patch reduces
746 the amount of text output, and generally makes it easier to review.
747 Note that non-Git "patch" programs won't understand renaming patches, so
748 use it only when you know the recipient uses Git to apply your patch.
750 * Extract three topmost commits from the current branch and format them
751 as e-mailable patches:
754 $ git format-patch -3
760 Note that `format-patch` will omit merge commits from the output, even
761 if they are part of the requested range. A simple "patch" does not
762 include enough information for the receiving end to reproduce the same
767 linkgit:git-am[1], linkgit:git-send-email[1]
771 Part of the linkgit:git[1] suite