Merge branch 'jc/maint-fnmatch-old-style-definition' into maint
[git/git.git] / Documentation / git-format-patch.txt
1 git-format-patch(1)
2 ===================
3
4 NAME
5 ----
6 git-format-patch - Prepare patches for e-mail submission
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git format-patch' [-k] [(-o|--output-directory) <dir> | --stdout]
13 [--no-thread | --thread[=<style>]]
14 [(--attach|--inline)[=<boundary>] | --no-attach]
15 [-s | --signoff]
16 [--signature=<signature> | --no-signature]
17 [-n | --numbered | -N | --no-numbered]
18 [--start-number <n>] [--numbered-files]
19 [--in-reply-to=Message-Id] [--suffix=.<sfx>]
20 [--ignore-if-in-upstream]
21 [--subject-prefix=Subject-Prefix]
22 [--to=<email>] [--cc=<email>]
23 [--cover-letter] [--quiet] [--notes[=<ref>]]
24 [<common diff options>]
25 [ <since> | <revision range> ]
26
27 DESCRIPTION
28 -----------
29
30 Prepare each commit with its patch in
31 one file per commit, formatted to resemble UNIX mailbox format.
32 The output of this command is convenient for e-mail submission or
33 for use with 'git am'.
34
35 There are two ways to specify which commits to operate on.
36
37 1. A single commit, <since>, specifies that the commits leading
38 to the tip of the current branch that are not in the history
39 that leads to the <since> to be output.
40
41 2. Generic <revision range> expression (see "SPECIFYING
42 REVISIONS" section in linkgit:gitrevisions[7]) means the
43 commits in the specified range.
44
45 The first rule takes precedence in the case of a single <commit>. To
46 apply the second rule, i.e., format everything since the beginning of
47 history up until <commit>, use the '\--root' option: `git format-patch
48 --root <commit>`. If you want to format only <commit> itself, you
49 can do this with `git format-patch -1 <commit>`.
50
51 By default, each output file is numbered sequentially from 1, and uses the
52 first line of the commit message (massaged for pathname safety) as
53 the filename. With the `--numbered-files` option, the output file names
54 will only be numbers, without the first line of the commit appended.
55 The names of the output files are printed to standard
56 output, unless the `--stdout` option is specified.
57
58 If `-o` is specified, output files are created in <dir>. Otherwise
59 they are created in the current working directory.
60
61 By default, the subject of a single patch is "[PATCH] " followed by
62 the concatenation of lines from the commit message up to the first blank
63 line (see the DISCUSSION section of linkgit:git-commit[1]).
64
65 When multiple patches are output, the subject prefix will instead be
66 "[PATCH n/m] ". To force 1/1 to be added for a single patch, use `-n`.
67 To omit patch numbers from the subject, use `-N`.
68
69 If given `--thread`, `git-format-patch` will generate `In-Reply-To` and
70 `References` headers to make the second and subsequent patch mails appear
71 as replies to the first mail; this also generates a `Message-Id` header to
72 reference.
73
74 OPTIONS
75 -------
76 :git-format-patch: 1
77 include::diff-options.txt[]
78
79 -<n>::
80 Prepare patches from the topmost <n> commits.
81
82 -o <dir>::
83 --output-directory <dir>::
84 Use <dir> to store the resulting files, instead of the
85 current working directory.
86
87 -n::
88 --numbered::
89 Name output in '[PATCH n/m]' format, even with a single patch.
90
91 -N::
92 --no-numbered::
93 Name output in '[PATCH]' format.
94
95 --start-number <n>::
96 Start numbering the patches at <n> instead of 1.
97
98 --numbered-files::
99 Output file names will be a simple number sequence
100 without the default first line of the commit appended.
101
102 -k::
103 --keep-subject::
104 Do not strip/add '[PATCH]' from the first line of the
105 commit log message.
106
107 -s::
108 --signoff::
109 Add `Signed-off-by:` line to the commit message, using
110 the committer identity of yourself.
111
112 --stdout::
113 Print all commits to the standard output in mbox format,
114 instead of creating a file for each one.
115
116 --attach[=<boundary>]::
117 Create multipart/mixed attachment, the first part of
118 which is the commit message and the patch itself in the
119 second part, with `Content-Disposition: attachment`.
120
121 --no-attach::
122 Disable the creation of an attachment, overriding the
123 configuration setting.
124
125 --inline[=<boundary>]::
126 Create multipart/mixed attachment, the first part of
127 which is the commit message and the patch itself in the
128 second part, with `Content-Disposition: inline`.
129
130 --thread[=<style>]::
131 --no-thread::
132 Controls addition of `In-Reply-To` and `References` headers to
133 make the second and subsequent mails appear as replies to the
134 first. Also controls generation of the `Message-Id` header to
135 reference.
136 +
137 The optional <style> argument can be either `shallow` or `deep`.
138 'shallow' threading makes every mail a reply to the head of the
139 series, where the head is chosen from the cover letter, the
140 `--in-reply-to`, and the first patch mail, in this order. 'deep'
141 threading makes every mail a reply to the previous one.
142 +
143 The default is `--no-thread`, unless the 'format.thread' configuration
144 is set. If `--thread` is specified without a style, it defaults to the
145 style specified by 'format.thread' if any, or else `shallow`.
146 +
147 Beware that the default for 'git send-email' is to thread emails
148 itself. If you want `git format-patch` to take care of threading, you
149 will want to ensure that threading is disabled for `git send-email`.
150
151 --in-reply-to=Message-Id::
152 Make the first mail (or all the mails with `--no-thread`) appear as a
153 reply to the given Message-Id, which avoids breaking threads to
154 provide a new patch series.
155
156 --ignore-if-in-upstream::
157 Do not include a patch that matches a commit in
158 <until>..<since>. This will examine all patches reachable
159 from <since> but not from <until> and compare them with the
160 patches being generated, and any patch that matches is
161 ignored.
162
163 --subject-prefix=<Subject-Prefix>::
164 Instead of the standard '[PATCH]' prefix in the subject
165 line, instead use '[<Subject-Prefix>]'. This
166 allows for useful naming of a patch series, and can be
167 combined with the `--numbered` option.
168
169 --to=<email>::
170 Add a `To:` header to the email headers. This is in addition
171 to any configured headers, and may be used multiple times.
172 The negated form `--no-to` discards all `To:` headers added so
173 far (from config or command line).
174
175 --cc=<email>::
176 Add a `Cc:` header to the email headers. This is in addition
177 to any configured headers, and may be used multiple times.
178 The negated form `--no-cc` discards all `Cc:` headers added so
179 far (from config or command line).
180
181 --add-header=<header>::
182 Add an arbitrary header to the email headers. This is in addition
183 to any configured headers, and may be used multiple times.
184 For example, `--add-header="Organization: git-foo"`.
185 The negated form `--no-add-header` discards *all* (`To:`,
186 `Cc:`, and custom) headers added so far from config or command
187 line.
188
189 --cover-letter::
190 In addition to the patches, generate a cover letter file
191 containing the shortlog and the overall diffstat. You can
192 fill in a description in the file before sending it out.
193
194 --notes[=<ref>]::
195 Append the notes (see linkgit:git-notes[1]) for the commit
196 after the three-dash line.
197 +
198 The expected use case of this is to write supporting explanation for
199 the commit that does not belong to the commit log message proper,
200 and include it with the patch submission. While one can simply write
201 these explanations after `format-patch` has run but before sending,
202 keeping them as git notes allows them to be maintained between versions
203 of the patch series (but see the discussion of the `notes.rewrite`
204 configuration options in linkgit:git-notes[1] to use this workflow).
205
206 --[no]-signature=<signature>::
207 Add a signature to each message produced. Per RFC 3676 the signature
208 is separated from the body by a line with '-- ' on it. If the
209 signature option is omitted the signature defaults to the git version
210 number.
211
212 --suffix=.<sfx>::
213 Instead of using `.patch` as the suffix for generated
214 filenames, use specified suffix. A common alternative is
215 `--suffix=.txt`. Leaving this empty will remove the `.patch`
216 suffix.
217 +
218 Note that the leading character does not have to be a dot; for example,
219 you can use `--suffix=-patch` to get `0001-description-of-my-change-patch`.
220
221 --quiet::
222 Do not print the names of the generated files to standard output.
223
224 --no-binary::
225 Do not output contents of changes in binary files, instead
226 display a notice that those files changed. Patches generated
227 using this option cannot be applied properly, but they are
228 still useful for code review.
229
230 --root::
231 Treat the revision argument as a <revision range>, even if it
232 is just a single commit (that would normally be treated as a
233 <since>). Note that root commits included in the specified
234 range are always formatted as creation patches, independently
235 of this flag.
236
237 CONFIGURATION
238 -------------
239 You can specify extra mail header lines to be added to each message,
240 defaults for the subject prefix and file suffix, number patches when
241 outputting more than one patch, add "To" or "Cc:" headers, configure
242 attachments, and sign off patches with configuration variables.
243
244 ------------
245 [format]
246 headers = "Organization: git-foo\n"
247 subjectprefix = CHANGE
248 suffix = .txt
249 numbered = auto
250 to = <email>
251 cc = <email>
252 attach [ = mime-boundary-string ]
253 signoff = true
254 ------------
255
256
257 DISCUSSION
258 ----------
259
260 The patch produced by 'git format-patch' is in UNIX mailbox format,
261 with a fixed "magic" time stamp to indicate that the file is output
262 from format-patch rather than a real mailbox, like so:
263
264 ------------
265 From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
266 From: Tony Luck <tony.luck@intel.com>
267 Date: Tue, 13 Jul 2010 11:42:54 -0700
268 Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
269 =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig=20diet?=
270 MIME-Version: 1.0
271 Content-Type: text/plain; charset=UTF-8
272 Content-Transfer-Encoding: 8bit
273
274 arch/arm config files were slimmed down using a python script
275 (See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)
276
277 Do the same for ia64 so we can have sleek & trim looking
278 ...
279 ------------
280
281 Typically it will be placed in a MUA's drafts folder, edited to add
282 timely commentary that should not go in the changelog after the three
283 dashes, and then sent as a message whose body, in our example, starts
284 with "arch/arm config files were...". On the receiving end, readers
285 can save interesting patches in a UNIX mailbox and apply them with
286 linkgit:git-am[1].
287
288 When a patch is part of an ongoing discussion, the patch generated by
289 'git format-patch' can be tweaked to take advantage of the 'git am
290 --scissors' feature. After your response to the discussion comes a
291 line that consists solely of "`-- >8 --`" (scissors and perforation),
292 followed by the patch with unnecessary header fields removed:
293
294 ------------
295 ...
296 > So we should do such-and-such.
297
298 Makes sense to me. How about this patch?
299
300 -- >8 --
301 Subject: [IA64] Put ia64 config files on the Uwe Kleine-K├Ânig diet
302
303 arch/arm config files were slimmed down using a python script
304 ...
305 ------------
306
307 When sending a patch this way, most often you are sending your own
308 patch, so in addition to the "`From $SHA1 $magic_timestamp`" marker you
309 should omit `From:` and `Date:` lines from the patch file. The patch
310 title is likely to be different from the subject of the discussion the
311 patch is in response to, so it is likely that you would want to keep
312 the Subject: line, like the example above.
313
314 Checking for patch corruption
315 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
316 Many mailers if not set up properly will corrupt whitespace. Here are
317 two common types of corruption:
318
319 * Empty context lines that do not have _any_ whitespace.
320
321 * Non-empty context lines that have one extra whitespace at the
322 beginning.
323
324 One way to test if your MUA is set up correctly is:
325
326 * Send the patch to yourself, exactly the way you would, except
327 with To: and Cc: lines that do not contain the list and
328 maintainer address.
329
330 * Save that patch to a file in UNIX mailbox format. Call it a.patch,
331 say.
332
333 * Apply it:
334
335 $ git fetch <project> master:test-apply
336 $ git checkout test-apply
337 $ git reset --hard
338 $ git am a.patch
339
340 If it does not apply correctly, there can be various reasons.
341
342 * The patch itself does not apply cleanly. That is _bad_ but
343 does not have much to do with your MUA. You might want to rebase
344 the patch with linkgit:git-rebase[1] before regenerating it in
345 this case.
346
347 * The MUA corrupted your patch; "am" would complain that
348 the patch does not apply. Look in the .git/rebase-apply/ subdirectory and
349 see what 'patch' file contains and check for the common
350 corruption patterns mentioned above.
351
352 * While at it, check the 'info' and 'final-commit' files as well.
353 If what is in 'final-commit' is not exactly what you would want to
354 see in the commit log message, it is very likely that the
355 receiver would end up hand editing the log message when applying
356 your patch. Things like "Hi, this is my first patch.\n" in the
357 patch e-mail should come after the three-dash line that signals
358 the end of the commit message.
359
360 MUA-SPECIFIC HINTS
361 ------------------
362 Here are some hints on how to successfully submit patches inline using
363 various mailers.
364
365 GMail
366 ~~~~~
367 GMail does not have any way to turn off line wrapping in the web
368 interface, so it will mangle any emails that you send. You can however
369 use "git send-email" and send your patches through the GMail SMTP server, or
370 use any IMAP email client to connect to the google IMAP server and forward
371 the emails through that.
372
373 For hints on using 'git send-email' to send your patches through the
374 GMail SMTP server, see the EXAMPLE section of linkgit:git-send-email[1].
375
376 For hints on submission using the IMAP interface, see the EXAMPLE
377 section of linkgit:git-imap-send[1].
378
379 Thunderbird
380 ~~~~~~~~~~~
381 By default, Thunderbird will both wrap emails as well as flag
382 them as being 'format=flowed', both of which will make the
383 resulting email unusable by git.
384
385 There are three different approaches: use an add-on to turn off line wraps,
386 configure Thunderbird to not mangle patches, or use
387 an external editor to keep Thunderbird from mangling the patches.
388
389 Approach #1 (add-on)
390 ^^^^^^^^^^^^^^^^^^^^
391
392 Install the Toggle Word Wrap add-on that is available from
393 https://addons.mozilla.org/thunderbird/addon/toggle-word-wrap/
394 It adds a menu entry "Enable Word Wrap" in the composer's "Options" menu
395 that you can tick off. Now you can compose the message as you otherwise do
396 (cut + paste, 'git format-patch' | 'git imap-send', etc), but you have to
397 insert line breaks manually in any text that you type.
398
399 Approach #2 (configuration)
400 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
401 Three steps:
402
403 1. Configure your mail server composition as plain text:
404 Edit...Account Settings...Composition & Addressing,
405 uncheck "Compose Messages in HTML".
406
407 2. Configure your general composition window to not wrap.
408 +
409 In Thunderbird 2:
410 Edit..Preferences..Composition, wrap plain text messages at 0
411 +
412 In Thunderbird 3:
413 Edit..Preferences..Advanced..Config Editor. Search for
414 "mail.wrap_long_lines".
415 Toggle it to make sure it is set to `false`.
416
417 3. Disable the use of format=flowed:
418 Edit..Preferences..Advanced..Config Editor. Search for
419 "mailnews.send_plaintext_flowed".
420 Toggle it to make sure it is set to `false`.
421
422 After that is done, you should be able to compose email as you
423 otherwise would (cut + paste, 'git format-patch' | 'git imap-send', etc),
424 and the patches will not be mangled.
425
426 Approach #3 (external editor)
427 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
428
429 The following Thunderbird extensions are needed:
430 AboutConfig from http://aboutconfig.mozdev.org/ and
431 External Editor from http://globs.org/articles.php?lng=en&pg=8
432
433 1. Prepare the patch as a text file using your method of choice.
434
435 2. Before opening a compose window, use Edit->Account Settings to
436 uncheck the "Compose messages in HTML format" setting in the
437 "Composition & Addressing" panel of the account to be used to
438 send the patch.
439
440 3. In the main Thunderbird window, 'before' you open the compose
441 window for the patch, use Tools->about:config to set the
442 following to the indicated values:
443 +
444 ----------
445 mailnews.send_plaintext_flowed => false
446 mailnews.wraplength => 0
447 ----------
448
449 4. Open a compose window and click the external editor icon.
450
451 5. In the external editor window, read in the patch file and exit
452 the editor normally.
453
454 Side note: it may be possible to do step 2 with
455 about:config and the following settings but no one's tried yet.
456
457 ----------
458 mail.html_compose => false
459 mail.identity.default.compose_html => false
460 mail.identity.id?.compose_html => false
461 ----------
462
463 There is a script in contrib/thunderbird-patch-inline which can help
464 you include patches with Thunderbird in an easy way. To use it, do the
465 steps above and then use the script as the external editor.
466
467 KMail
468 ~~~~~
469 This should help you to submit patches inline using KMail.
470
471 1. Prepare the patch as a text file.
472
473 2. Click on New Mail.
474
475 3. Go under "Options" in the Composer window and be sure that
476 "Word wrap" is not set.
477
478 4. Use Message -> Insert file... and insert the patch.
479
480 5. Back in the compose window: add whatever other text you wish to the
481 message, complete the addressing and subject fields, and press send.
482
483
484 EXAMPLES
485 --------
486
487 * Extract commits between revisions R1 and R2, and apply them on top of
488 the current branch using 'git am' to cherry-pick them:
489 +
490 ------------
491 $ git format-patch -k --stdout R1..R2 | git am -3 -k
492 ------------
493
494 * Extract all commits which are in the current branch but not in the
495 origin branch:
496 +
497 ------------
498 $ git format-patch origin
499 ------------
500 +
501 For each commit a separate file is created in the current directory.
502
503 * Extract all commits that lead to 'origin' since the inception of the
504 project:
505 +
506 ------------
507 $ git format-patch --root origin
508 ------------
509
510 * The same as the previous one:
511 +
512 ------------
513 $ git format-patch -M -B origin
514 ------------
515 +
516 Additionally, it detects and handles renames and complete rewrites
517 intelligently to produce a renaming patch. A renaming patch reduces
518 the amount of text output, and generally makes it easier to review.
519 Note that non-git "patch" programs won't understand renaming patches, so
520 use it only when you know the recipient uses git to apply your patch.
521
522 * Extract three topmost commits from the current branch and format them
523 as e-mailable patches:
524 +
525 ------------
526 $ git format-patch -3
527 ------------
528
529 SEE ALSO
530 --------
531 linkgit:git-am[1], linkgit:git-send-email[1]
532
533 GIT
534 ---
535 Part of the linkgit:git[1] suite