1GIT-FORMAT-PATCH(1)               Git Manual               GIT-FORMAT-PATCH(1)
2
3
4

NAME

6       git-format-patch - Prepare patches for e-mail submission
7

SYNOPSIS

9       git format-patch [-k] [(-o|--output-directory) <dir> | --stdout]
10                          [--no-thread | --thread[=<style>]]
11                          [(--attach|--inline)[=<boundary>] | --no-attach]
12                          [-s | --signoff]
13                          [--signature=<signature> | --no-signature]
14                          [--signature-file=<file>]
15                          [-n | --numbered | -N | --no-numbered]
16                          [--start-number <n>] [--numbered-files]
17                          [--in-reply-to=<message id>] [--suffix=.<sfx>]
18                          [--ignore-if-in-upstream] [--always]
19                          [--cover-from-description=<mode>]
20                          [--rfc] [--subject-prefix=<subject prefix>]
21                          [(--reroll-count|-v) <n>]
22                          [--to=<email>] [--cc=<email>]
23                          [--[no-]cover-letter] [--quiet]
24                          [--[no-]encode-email-headers]
25                          [--no-notes | --notes[=<ref>]]
26                          [--interdiff=<previous>]
27                          [--range-diff=<previous> [--creation-factor=<percent>]]
28                          [--filename-max-length=<n>]
29                          [--progress]
30                          [<common diff options>]
31                          [ <since> | <revision range> ]
32

DESCRIPTION

34       Prepare each non-merge commit with its "patch" in one "message" per
35       commit, formatted to resemble a UNIX mailbox. The output of this
36       command is convenient for e-mail submission or for use with git am.
37
38       A "message" generated by the command consists of three parts:
39
40       •   A brief metadata header that begins with From <commit> with a fixed
41           Mon Sep 17 00:00:00 2001 datestamp to help programs like "file(1)"
42           to recognize that the file is an output from this command, fields
43           that record the author identity, the author date, and the title of
44           the change (taken from the first paragraph of the commit log
45           message).
46
47       •   The second and subsequent paragraphs of the commit log message.
48
49       •   The "patch", which is the "diff -p --stat" output (see git-diff(1))
50           between the commit and its parent.
51
52       The log message and the patch is separated by a line with a three-dash
53       line.
54
55       There are two ways to specify which commits to operate on.
56
57        1. A single commit, <since>, specifies that the commits leading to the
58           tip of the current branch that are not in the history that leads to
59           the <since> to be output.
60
61        2. Generic <revision range> expression (see "SPECIFYING REVISIONS"
62           section in gitrevisions(7)) means the commits in the specified
63           range.
64
65       The first rule takes precedence in the case of a single <commit>. To
66       apply the second rule, i.e., format everything since the beginning of
67       history up until <commit>, use the --root option: git format-patch
68       --root <commit>. If you want to format only <commit> itself, you can do
69       this with git format-patch -1 <commit>.
70
71       By default, each output file is numbered sequentially from 1, and uses
72       the first line of the commit message (massaged for pathname safety) as
73       the filename. With the --numbered-files option, the output file names
74       will only be numbers, without the first line of the commit appended.
75       The names of the output files are printed to standard output, unless
76       the --stdout option is specified.
77
78       If -o is specified, output files are created in <dir>. Otherwise they
79       are created in the current working directory. The default path can be
80       set with the format.outputDirectory configuration option. The -o option
81       takes precedence over format.outputDirectory. To store patches in the
82       current working directory even when format.outputDirectory points
83       elsewhere, use -o .. All directory components will be created.
84
85       By default, the subject of a single patch is "[PATCH] " followed by the
86       concatenation of lines from the commit message up to the first blank
87       line (see the DISCUSSION section of git-commit(1)).
88
89       When multiple patches are output, the subject prefix will instead be
90       "[PATCH n/m] ". To force 1/1 to be added for a single patch, use -n. To
91       omit patch numbers from the subject, use -N.
92
93       If given --thread, git-format-patch will generate In-Reply-To and
94       References headers to make the second and subsequent patch mails appear
95       as replies to the first mail; this also generates a Message-Id header
96       to reference.
97

OPTIONS

99       -p, --no-stat
100           Generate plain patches without any diffstats.
101
102       -U<n>, --unified=<n>
103           Generate diffs with <n> lines of context instead of the usual
104           three.
105
106       --output=<file>
107           Output to a specific file instead of stdout.
108
109       --output-indicator-new=<char>, --output-indicator-old=<char>,
110       --output-indicator-context=<char>
111           Specify the character used to indicate new, old or context lines in
112           the generated patch. Normally they are +, - and ' ' respectively.
113
114       --indent-heuristic
115           Enable the heuristic that shifts diff hunk boundaries to make
116           patches easier to read. This is the default.
117
118       --no-indent-heuristic
119           Disable the indent heuristic.
120
121       --minimal
122           Spend extra time to make sure the smallest possible diff is
123           produced.
124
125       --patience
126           Generate a diff using the "patience diff" algorithm.
127
128       --histogram
129           Generate a diff using the "histogram diff" algorithm.
130
131       --anchored=<text>
132           Generate a diff using the "anchored diff" algorithm.
133
134           This option may be specified more than once.
135
136           If a line exists in both the source and destination, exists only
137           once, and starts with this text, this algorithm attempts to prevent
138           it from appearing as a deletion or addition in the output. It uses
139           the "patience diff" algorithm internally.
140
141       --diff-algorithm={patience|minimal|histogram|myers}
142           Choose a diff algorithm. The variants are as follows:
143
144           default, myers
145               The basic greedy diff algorithm. Currently, this is the
146               default.
147
148           minimal
149               Spend extra time to make sure the smallest possible diff is
150               produced.
151
152           patience
153               Use "patience diff" algorithm when generating patches.
154
155           histogram
156               This algorithm extends the patience algorithm to "support
157               low-occurrence common elements".
158
159           For instance, if you configured the diff.algorithm variable to a
160           non-default value and want to use the default one, then you have to
161           use --diff-algorithm=default option.
162
163       --stat[=<width>[,<name-width>[,<count>]]]
164           Generate a diffstat. By default, as much space as necessary will be
165           used for the filename part, and the rest for the graph part.
166           Maximum width defaults to terminal width, or 80 columns if not
167           connected to a terminal, and can be overridden by <width>. The
168           width of the filename part can be limited by giving another width
169           <name-width> after a comma. The width of the graph part can be
170           limited by using --stat-graph-width=<width> (affects all commands
171           generating a stat graph) or by setting diff.statGraphWidth=<width>
172           (does not affect git format-patch). By giving a third parameter
173           <count>, you can limit the output to the first <count> lines,
174           followed by ...  if there are more.
175
176           These parameters can also be set individually with
177           --stat-width=<width>, --stat-name-width=<name-width> and
178           --stat-count=<count>.
179
180       --compact-summary
181           Output a condensed summary of extended header information such as
182           file creations or deletions ("new" or "gone", optionally "+l" if
183           it’s a symlink) and mode changes ("+x" or "-x" for adding or
184           removing executable bit respectively) in diffstat. The information
185           is put between the filename part and the graph part. Implies
186           --stat.
187
188       --numstat
189           Similar to --stat, but shows number of added and deleted lines in
190           decimal notation and pathname without abbreviation, to make it more
191           machine friendly. For binary files, outputs two - instead of saying
192           0 0.
193
194       --shortstat
195           Output only the last line of the --stat format containing total
196           number of modified files, as well as number of added and deleted
197           lines.
198
199       -X[<param1,param2,...>], --dirstat[=<param1,param2,...>]
200           Output the distribution of relative amount of changes for each
201           sub-directory. The behavior of --dirstat can be customized by
202           passing it a comma separated list of parameters. The defaults are
203           controlled by the diff.dirstat configuration variable (see git-
204           config(1)). The following parameters are available:
205
206           changes
207               Compute the dirstat numbers by counting the lines that have
208               been removed from the source, or added to the destination. This
209               ignores the amount of pure code movements within a file. In
210               other words, rearranging lines in a file is not counted as much
211               as other changes. This is the default behavior when no
212               parameter is given.
213
214           lines
215               Compute the dirstat numbers by doing the regular line-based
216               diff analysis, and summing the removed/added line counts. (For
217               binary files, count 64-byte chunks instead, since binary files
218               have no natural concept of lines). This is a more expensive
219               --dirstat behavior than the changes behavior, but it does count
220               rearranged lines within a file as much as other changes. The
221               resulting output is consistent with what you get from the other
222               --*stat options.
223
224           files
225               Compute the dirstat numbers by counting the number of files
226               changed. Each changed file counts equally in the dirstat
227               analysis. This is the computationally cheapest --dirstat
228               behavior, since it does not have to look at the file contents
229               at all.
230
231           cumulative
232               Count changes in a child directory for the parent directory as
233               well. Note that when using cumulative, the sum of the
234               percentages reported may exceed 100%. The default
235               (non-cumulative) behavior can be specified with the
236               noncumulative parameter.
237
238           <limit>
239               An integer parameter specifies a cut-off percent (3% by
240               default). Directories contributing less than this percentage of
241               the changes are not shown in the output.
242
243           Example: The following will count changed files, while ignoring
244           directories with less than 10% of the total amount of changed
245           files, and accumulating child directory counts in the parent
246           directories: --dirstat=files,10,cumulative.
247
248       --cumulative
249           Synonym for --dirstat=cumulative
250
251       --dirstat-by-file[=<param1,param2>...]
252           Synonym for --dirstat=files,param1,param2...
253
254       --summary
255           Output a condensed summary of extended header information such as
256           creations, renames and mode changes.
257
258       --no-renames
259           Turn off rename detection, even when the configuration file gives
260           the default to do so.
261
262       --[no-]rename-empty
263           Whether to use empty blobs as rename source.
264
265       --full-index
266           Instead of the first handful of characters, show the full pre- and
267           post-image blob object names on the "index" line when generating
268           patch format output.
269
270       --binary
271           In addition to --full-index, output a binary diff that can be
272           applied with git-apply.
273
274       --abbrev[=<n>]
275           Instead of showing the full 40-byte hexadecimal object name in
276           diff-raw format output and diff-tree header lines, show the
277           shortest prefix that is at least <n> hexdigits long that uniquely
278           refers the object. In diff-patch output format, --full-index takes
279           higher precedence, i.e. if --full-index is specified, full blob
280           names will be shown regardless of --abbrev. Non default number of
281           digits can be specified with --abbrev=<n>.
282
283       -B[<n>][/<m>], --break-rewrites[=[<n>][/<m>]]
284           Break complete rewrite changes into pairs of delete and create.
285           This serves two purposes:
286
287           It affects the way a change that amounts to a total rewrite of a
288           file not as a series of deletion and insertion mixed together with
289           a very few lines that happen to match textually as the context, but
290           as a single deletion of everything old followed by a single
291           insertion of everything new, and the number m controls this aspect
292           of the -B option (defaults to 60%).  -B/70% specifies that less
293           than 30% of the original should remain in the result for Git to
294           consider it a total rewrite (i.e. otherwise the resulting patch
295           will be a series of deletion and insertion mixed together with
296           context lines).
297
298           When used with -M, a totally-rewritten file is also considered as
299           the source of a rename (usually -M only considers a file that
300           disappeared as the source of a rename), and the number n controls
301           this aspect of the -B option (defaults to 50%).  -B20% specifies
302           that a change with addition and deletion compared to 20% or more of
303           the file’s size are eligible for being picked up as a possible
304           source of a rename to another file.
305
306       -M[<n>], --find-renames[=<n>]
307           Detect renames. If n is specified, it is a threshold on the
308           similarity index (i.e. amount of addition/deletions compared to the
309           file’s size). For example, -M90% means Git should consider a
310           delete/add pair to be a rename if more than 90% of the file hasn’t
311           changed. Without a % sign, the number is to be read as a fraction,
312           with a decimal point before it. I.e., -M5 becomes 0.5, and is thus
313           the same as -M50%. Similarly, -M05 is the same as -M5%. To limit
314           detection to exact renames, use -M100%. The default similarity
315           index is 50%.
316
317       -C[<n>], --find-copies[=<n>]
318           Detect copies as well as renames. See also --find-copies-harder. If
319           n is specified, it has the same meaning as for -M<n>.
320
321       --find-copies-harder
322           For performance reasons, by default, -C option finds copies only if
323           the original file of the copy was modified in the same changeset.
324           This flag makes the command inspect unmodified files as candidates
325           for the source of copy. This is a very expensive operation for
326           large projects, so use it with caution. Giving more than one -C
327           option has the same effect.
328
329       -D, --irreversible-delete
330           Omit the preimage for deletes, i.e. print only the header but not
331           the diff between the preimage and /dev/null. The resulting patch is
332           not meant to be applied with patch or git apply; this is solely for
333           people who want to just concentrate on reviewing the text after the
334           change. In addition, the output obviously lacks enough information
335           to apply such a patch in reverse, even manually, hence the name of
336           the option.
337
338           When used together with -B, omit also the preimage in the deletion
339           part of a delete/create pair.
340
341       -l<num>
342           The -M and -C options involve some preliminary steps that can
343           detect subsets of renames/copies cheaply, followed by an exhaustive
344           fallback portion that compares all remaining unpaired destinations
345           to all relevant sources. (For renames, only remaining unpaired
346           sources are relevant; for copies, all original sources are
347           relevant.) For N sources and destinations, this exhaustive check is
348           O(N^2). This option prevents the exhaustive portion of rename/copy
349           detection from running if the number of source/destination files
350           involved exceeds the specified number. Defaults to
351           diff.renameLimit. Note that a value of 0 is treated as unlimited.
352
353       -O<orderfile>
354           Control the order in which files appear in the output. This
355           overrides the diff.orderFile configuration variable (see git-
356           config(1)). To cancel diff.orderFile, use -O/dev/null.
357
358           The output order is determined by the order of glob patterns in
359           <orderfile>. All files with pathnames that match the first pattern
360           are output first, all files with pathnames that match the second
361           pattern (but not the first) are output next, and so on. All files
362           with pathnames that do not match any pattern are output last, as if
363           there was an implicit match-all pattern at the end of the file. If
364           multiple pathnames have the same rank (they match the same pattern
365           but no earlier patterns), their output order relative to each other
366           is the normal order.
367
368           <orderfile> is parsed as follows:
369
370           •   Blank lines are ignored, so they can be used as separators for
371               readability.
372
373           •   Lines starting with a hash ("#") are ignored, so they can be
374               used for comments. Add a backslash ("\") to the beginning of
375               the pattern if it starts with a hash.
376
377           •   Each other line contains a single pattern.
378
379           Patterns have the same syntax and semantics as patterns used for
380           fnmatch(3) without the FNM_PATHNAME flag, except a pathname also
381           matches a pattern if removing any number of the final pathname
382           components matches the pattern. For example, the pattern "foo*bar"
383           matches "fooasdfbar" and "foo/bar/baz/asdf" but not "foobarx".
384
385       --skip-to=<file>, --rotate-to=<file>
386           Discard the files before the named <file> from the output (i.e.
387           skip to), or move them to the end of the output (i.e.  rotate to).
388           These were invented primarily for use of the git difftool command,
389           and may not be very useful otherwise.
390
391       --relative[=<path>], --no-relative
392           When run from a subdirectory of the project, it can be told to
393           exclude changes outside the directory and show pathnames relative
394           to it with this option. When you are not in a subdirectory (e.g. in
395           a bare repository), you can name which subdirectory to make the
396           output relative to by giving a <path> as an argument.
397           --no-relative can be used to countermand both diff.relative config
398           option and previous --relative.
399
400       -a, --text
401           Treat all files as text.
402
403       --ignore-cr-at-eol
404           Ignore carriage-return at the end of line when doing a comparison.
405
406       --ignore-space-at-eol
407           Ignore changes in whitespace at EOL.
408
409       -b, --ignore-space-change
410           Ignore changes in amount of whitespace. This ignores whitespace at
411           line end, and considers all other sequences of one or more
412           whitespace characters to be equivalent.
413
414       -w, --ignore-all-space
415           Ignore whitespace when comparing lines. This ignores differences
416           even if one line has whitespace where the other line has none.
417
418       --ignore-blank-lines
419           Ignore changes whose lines are all blank.
420
421       -I<regex>, --ignore-matching-lines=<regex>
422           Ignore changes whose all lines match <regex>. This option may be
423           specified more than once.
424
425       --inter-hunk-context=<lines>
426           Show the context between diff hunks, up to the specified number of
427           lines, thereby fusing hunks that are close to each other. Defaults
428           to diff.interHunkContext or 0 if the config option is unset.
429
430       -W, --function-context
431           Show whole function as context lines for each change. The function
432           names are determined in the same way as git diff works out patch
433           hunk headers (see Defining a custom hunk-header in
434           gitattributes(5)).
435
436       --ext-diff
437           Allow an external diff helper to be executed. If you set an
438           external diff driver with gitattributes(5), you need to use this
439           option with git-log(1) and friends.
440
441       --no-ext-diff
442           Disallow external diff drivers.
443
444       --textconv, --no-textconv
445           Allow (or disallow) external text conversion filters to be run when
446           comparing binary files. See gitattributes(5) for details. Because
447           textconv filters are typically a one-way conversion, the resulting
448           diff is suitable for human consumption, but cannot be applied. For
449           this reason, textconv filters are enabled by default only for git-
450           diff(1) and git-log(1), but not for git-format-patch(1) or diff
451           plumbing commands.
452
453       --ignore-submodules[=<when>]
454           Ignore changes to submodules in the diff generation. <when> can be
455           either "none", "untracked", "dirty" or "all", which is the default.
456           Using "none" will consider the submodule modified when it either
457           contains untracked or modified files or its HEAD differs from the
458           commit recorded in the superproject and can be used to override any
459           settings of the ignore option in git-config(1) or gitmodules(5).
460           When "untracked" is used submodules are not considered dirty when
461           they only contain untracked content (but they are still scanned for
462           modified content). Using "dirty" ignores all changes to the work
463           tree of submodules, only changes to the commits stored in the
464           superproject are shown (this was the behavior until 1.7.0). Using
465           "all" hides all changes to submodules.
466
467       --src-prefix=<prefix>
468           Show the given source prefix instead of "a/".
469
470       --dst-prefix=<prefix>
471           Show the given destination prefix instead of "b/".
472
473       --no-prefix
474           Do not show any source or destination prefix.
475
476       --line-prefix=<prefix>
477           Prepend an additional prefix to every line of output.
478
479       --ita-invisible-in-index
480           By default entries added by "git add -N" appear as an existing
481           empty file in "git diff" and a new file in "git diff --cached".
482           This option makes the entry appear as a new file in "git diff" and
483           non-existent in "git diff --cached". This option could be reverted
484           with --ita-visible-in-index. Both options are experimental and
485           could be removed in future.
486
487       For more detailed explanation on these common options, see also
488       gitdiffcore(7).
489
490       -<n>
491           Prepare patches from the topmost <n> commits.
492
493       -o <dir>, --output-directory <dir>
494           Use <dir> to store the resulting files, instead of the current
495           working directory.
496
497       -n, --numbered
498           Name output in [PATCH n/m] format, even with a single patch.
499
500       -N, --no-numbered
501           Name output in [PATCH] format.
502
503       --start-number <n>
504           Start numbering the patches at <n> instead of 1.
505
506       --numbered-files
507           Output file names will be a simple number sequence without the
508           default first line of the commit appended.
509
510       -k, --keep-subject
511           Do not strip/add [PATCH] from the first line of the commit log
512           message.
513
514       -s, --signoff
515           Add a Signed-off-by trailer to the commit message, using the
516           committer identity of yourself. See the signoff option in git-
517           commit(1) for more information.
518
519       --stdout
520           Print all commits to the standard output in mbox format, instead of
521           creating a file for each one.
522
523       --attach[=<boundary>]
524           Create multipart/mixed attachment, the first part of which is the
525           commit message and the patch itself in the second part, with
526           Content-Disposition: attachment.
527
528       --no-attach
529           Disable the creation of an attachment, overriding the configuration
530           setting.
531
532       --inline[=<boundary>]
533           Create multipart/mixed attachment, the first part of which is the
534           commit message and the patch itself in the second part, with
535           Content-Disposition: inline.
536
537       --thread[=<style>], --no-thread
538           Controls addition of In-Reply-To and References headers to make the
539           second and subsequent mails appear as replies to the first. Also
540           controls generation of the Message-Id header to reference.
541
542           The optional <style> argument can be either shallow or deep.
543           shallow threading makes every mail a reply to the head of the
544           series, where the head is chosen from the cover letter, the
545           --in-reply-to, and the first patch mail, in this order.  deep
546           threading makes every mail a reply to the previous one.
547
548           The default is --no-thread, unless the format.thread configuration
549           is set. If --thread is specified without a style, it defaults to
550           the style specified by format.thread if any, or else shallow.
551
552           Beware that the default for git send-email is to thread emails
553           itself. If you want git format-patch to take care of threading, you
554           will want to ensure that threading is disabled for git send-email.
555
556       --in-reply-to=<message id>
557           Make the first mail (or all the mails with --no-thread) appear as a
558           reply to the given <message id>, which avoids breaking threads to
559           provide a new patch series.
560
561       --ignore-if-in-upstream
562           Do not include a patch that matches a commit in <until>..<since>.
563           This will examine all patches reachable from <since> but not from
564           <until> and compare them with the patches being generated, and any
565           patch that matches is ignored.
566
567       --always
568           Include patches for commits that do not introduce any change, which
569           are omitted by default.
570
571       --cover-from-description=<mode>
572           Controls which parts of the cover letter will be automatically
573           populated using the branch’s description.
574
575           If <mode> is message or default, the cover letter subject will be
576           populated with placeholder text. The body of the cover letter will
577           be populated with the branch’s description. This is the default
578           mode when no configuration nor command line option is specified.
579
580           If <mode> is subject, the first paragraph of the branch description
581           will populate the cover letter subject. The remainder of the
582           description will populate the body of the cover letter.
583
584           If <mode> is auto, if the first paragraph of the branch description
585           is greater than 100 bytes, then the mode will be message, otherwise
586           subject will be used.
587
588           If <mode> is none, both the cover letter subject and body will be
589           populated with placeholder text.
590
591       --subject-prefix=<subject prefix>
592           Instead of the standard [PATCH] prefix in the subject line, instead
593           use [<subject prefix>]. This allows for useful naming of a patch
594           series, and can be combined with the --numbered option.
595
596       --filename-max-length=<n>
597           Instead of the standard 64 bytes, chomp the generated output
598           filenames at around <n> bytes (too short a value will be silently
599           raised to a reasonable length). Defaults to the value of the
600           format.filenameMaxLength configuration variable, or 64 if
601           unconfigured.
602
603       --rfc
604           Alias for --subject-prefix="RFC PATCH". RFC means "Request For
605           Comments"; use this when sending an experimental patch for
606           discussion rather than application.
607
608       -v <n>, --reroll-count=<n>
609           Mark the series as the <n>-th iteration of the topic. The output
610           filenames have v<n> prepended to them, and the subject prefix
611           ("PATCH" by default, but configurable via the --subject-prefix
612           option) has ` v<n>` appended to it. E.g.  --reroll-count=4 may
613           produce v4-0001-add-makefile.patch file that has "Subject: [PATCH
614           v4 1/20] Add makefile" in it.  <n> does not have to be an integer
615           (e.g. "--reroll-count=4.4", or "--reroll-count=4rev2" are allowed),
616           but the downside of using such a reroll-count is that the
617           range-diff/interdiff with the previous version does not state
618           exactly which version the new interation is compared against.
619
620       --to=<email>
621           Add a To: header to the email headers. This is in addition to any
622           configured headers, and may be used multiple times. The negated
623           form --no-to discards all To: headers added so far (from config or
624           command line).
625
626       --cc=<email>
627           Add a Cc: header to the email headers. This is in addition to any
628           configured headers, and may be used multiple times. The negated
629           form --no-cc discards all Cc: headers added so far (from config or
630           command line).
631
632       --from, --from=<ident>
633           Use ident in the From: header of each commit email. If the author
634           ident of the commit is not textually identical to the provided
635           ident, place a From: header in the body of the message with the
636           original author. If no ident is given, use the committer ident.
637
638           Note that this option is only useful if you are actually sending
639           the emails and want to identify yourself as the sender, but retain
640           the original author (and git am will correctly pick up the in-body
641           header). Note also that git send-email already handles this
642           transformation for you, and this option should not be used if you
643           are feeding the result to git send-email.
644
645       --[no-]force-in-body-from
646           With the e-mail sender specified via the --from option, by default,
647           an in-body "From:" to identify the real author of the commit is
648           added at the top of the commit log message if the sender is
649           different from the author. With this option, the in-body "From:" is
650           added even when the sender and the author have the same name and
651           address, which may help if the mailing list software mangles the
652           sender’s identity. Defaults to the value of the
653           format.forceInBodyFrom configuration variable.
654
655       --add-header=<header>
656           Add an arbitrary header to the email headers. This is in addition
657           to any configured headers, and may be used multiple times. For
658           example, --add-header="Organization: git-foo". The negated form
659           --no-add-header discards all (To:, Cc:, and custom) headers added
660           so far from config or command line.
661
662       --[no-]cover-letter
663           In addition to the patches, generate a cover letter file containing
664           the branch description, shortlog and the overall diffstat. You can
665           fill in a description in the file before sending it out.
666
667       --encode-email-headers, --no-encode-email-headers
668           Encode email headers that have non-ASCII characters with
669           "Q-encoding" (described in RFC 2047), instead of outputting the
670           headers verbatim. Defaults to the value of the
671           format.encodeEmailHeaders configuration variable.
672
673       --interdiff=<previous>
674           As a reviewer aid, insert an interdiff into the cover letter, or as
675           commentary of the lone patch of a 1-patch series, showing the
676           differences between the previous version of the patch series and
677           the series currently being formatted.  previous is a single
678           revision naming the tip of the previous series which shares a
679           common base with the series being formatted (for example git
680           format-patch --cover-letter --interdiff=feature/v1 -3 feature/v2).
681
682       --range-diff=<previous>
683           As a reviewer aid, insert a range-diff (see git-range-diff(1)) into
684           the cover letter, or as commentary of the lone patch of a 1-patch
685           series, showing the differences between the previous version of the
686           patch series and the series currently being formatted.  previous
687           can be a single revision naming the tip of the previous series if
688           it shares a common base with the series being formatted (for
689           example git format-patch --cover-letter --range-diff=feature/v1 -3
690           feature/v2), or a revision range if the two versions of the series
691           are disjoint (for example git format-patch --cover-letter
692           --range-diff=feature/v1~3..feature/v1 -3 feature/v2).
693
694           Note that diff options passed to the command affect how the primary
695           product of format-patch is generated, and they are not passed to
696           the underlying range-diff machinery used to generate the
697           cover-letter material (this may change in the future).
698
699       --creation-factor=<percent>
700           Used with --range-diff, tweak the heuristic which matches up
701           commits between the previous and current series of patches by
702           adjusting the creation/deletion cost fudge factor. See git-range-
703           diff(1)) for details.
704
705       --notes[=<ref>], --no-notes
706           Append the notes (see git-notes(1)) for the commit after the
707           three-dash line.
708
709           The expected use case of this is to write supporting explanation
710           for the commit that does not belong to the commit log message
711           proper, and include it with the patch submission. While one can
712           simply write these explanations after format-patch has run but
713           before sending, keeping them as Git notes allows them to be
714           maintained between versions of the patch series (but see the
715           discussion of the notes.rewrite configuration options in git-
716           notes(1) to use this workflow).
717
718           The default is --no-notes, unless the format.notes configuration is
719           set.
720
721       --[no-]signature=<signature>
722           Add a signature to each message produced. Per RFC 3676 the
723           signature is separated from the body by a line with '-- ' on it. If
724           the signature option is omitted the signature defaults to the Git
725           version number.
726
727       --signature-file=<file>
728           Works just like --signature except the signature is read from a
729           file.
730
731       --suffix=.<sfx>
732           Instead of using .patch as the suffix for generated filenames, use
733           specified suffix. A common alternative is --suffix=.txt. Leaving
734           this empty will remove the .patch suffix.
735
736           Note that the leading character does not have to be a dot; for
737           example, you can use --suffix=-patch to get
738           0001-description-of-my-change-patch.
739
740       -q, --quiet
741           Do not print the names of the generated files to standard output.
742
743       --no-binary
744           Do not output contents of changes in binary files, instead display
745           a notice that those files changed. Patches generated using this
746           option cannot be applied properly, but they are still useful for
747           code review.
748
749       --zero-commit
750           Output an all-zero hash in each patch’s From header instead of the
751           hash of the commit.
752
753       --[no-]base[=<commit>]
754           Record the base tree information to identify the state the patch
755           series applies to. See the BASE TREE INFORMATION section below for
756           details. If <commit> is "auto", a base commit is automatically
757           chosen. The --no-base option overrides a format.useAutoBase
758           configuration.
759
760       --root
761           Treat the revision argument as a <revision range>, even if it is
762           just a single commit (that would normally be treated as a <since>).
763           Note that root commits included in the specified range are always
764           formatted as creation patches, independently of this flag.
765
766       --progress
767           Show progress reports on stderr as patches are generated.
768

CONFIGURATION

770       You can specify extra mail header lines to be added to each message,
771       defaults for the subject prefix and file suffix, number patches when
772       outputting more than one patch, add "To:" or "Cc:" headers, configure
773       attachments, change the patch output directory, and sign off patches
774       with configuration variables.
775
776           [format]
777                   headers = "Organization: git-foo\n"
778                   subjectPrefix = CHANGE
779                   suffix = .txt
780                   numbered = auto
781                   to = <email>
782                   cc = <email>
783                   attach [ = mime-boundary-string ]
784                   signOff = true
785                   outputDirectory = <directory>
786                   coverLetter = auto
787                   coverFromDescription = auto
788

DISCUSSION

790       The patch produced by git format-patch is in UNIX mailbox format, with
791       a fixed "magic" time stamp to indicate that the file is output from
792       format-patch rather than a real mailbox, like so:
793
794           From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
795           From: Tony Luck <tony.luck@intel.com>
796           Date: Tue, 13 Jul 2010 11:42:54 -0700
797           Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
798            =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig=20diet?=
799           MIME-Version: 1.0
800           Content-Type: text/plain; charset=UTF-8
801           Content-Transfer-Encoding: 8bit
802
803           arch/arm config files were slimmed down using a python script
804           (See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)
805
806           Do the same for ia64 so we can have sleek & trim looking
807           ...
808
809       Typically it will be placed in a MUA’s drafts folder, edited to add
810       timely commentary that should not go in the changelog after the three
811       dashes, and then sent as a message whose body, in our example, starts
812       with "arch/arm config files were...". On the receiving end, readers can
813       save interesting patches in a UNIX mailbox and apply them with git-
814       am(1).
815
816       When a patch is part of an ongoing discussion, the patch generated by
817       git format-patch can be tweaked to take advantage of the git am
818       --scissors feature. After your response to the discussion comes a line
819       that consists solely of "-- >8 --" (scissors and perforation), followed
820       by the patch with unnecessary header fields removed:
821
822           ...
823           > So we should do such-and-such.
824
825           Makes sense to me.  How about this patch?
826
827           -- >8 --
828           Subject: [IA64] Put ia64 config files on the Uwe Kleine-König diet
829
830           arch/arm config files were slimmed down using a python script
831           ...
832
833       When sending a patch this way, most often you are sending your own
834       patch, so in addition to the "From $SHA1 $magic_timestamp" marker you
835       should omit From: and Date: lines from the patch file. The patch title
836       is likely to be different from the subject of the discussion the patch
837       is in response to, so it is likely that you would want to keep the
838       Subject: line, like the example above.
839
840   Checking for patch corruption
841       Many mailers if not set up properly will corrupt whitespace. Here are
842       two common types of corruption:
843
844       •   Empty context lines that do not have any whitespace.
845
846       •   Non-empty context lines that have one extra whitespace at the
847           beginning.
848
849       One way to test if your MUA is set up correctly is:
850
851       •   Send the patch to yourself, exactly the way you would, except with
852           To: and Cc: lines that do not contain the list and maintainer
853           address.
854
855       •   Save that patch to a file in UNIX mailbox format. Call it a.patch,
856           say.
857
858       •   Apply it:
859
860               $ git fetch <project> master:test-apply
861               $ git switch test-apply
862               $ git restore --source=HEAD --staged --worktree :/
863               $ git am a.patch
864
865       If it does not apply correctly, there can be various reasons.
866
867       •   The patch itself does not apply cleanly. That is bad but does not
868           have much to do with your MUA. You might want to rebase the patch
869           with git-rebase(1) before regenerating it in this case.
870
871       •   The MUA corrupted your patch; "am" would complain that the patch
872           does not apply. Look in the .git/rebase-apply/ subdirectory and see
873           what patch file contains and check for the common corruption
874           patterns mentioned above.
875
876       •   While at it, check the info and final-commit files as well. If what
877           is in final-commit is not exactly what you would want to see in the
878           commit log message, it is very likely that the receiver would end
879           up hand editing the log message when applying your patch. Things
880           like "Hi, this is my first patch.\n" in the patch e-mail should
881           come after the three-dash line that signals the end of the commit
882           message.
883

MUA-SPECIFIC HINTS

885       Here are some hints on how to successfully submit patches inline using
886       various mailers.
887
888   GMail
889       GMail does not have any way to turn off line wrapping in the web
890       interface, so it will mangle any emails that you send. You can however
891       use "git send-email" and send your patches through the GMail SMTP
892       server, or use any IMAP email client to connect to the google IMAP
893       server and forward the emails through that.
894
895       For hints on using git send-email to send your patches through the
896       GMail SMTP server, see the EXAMPLE section of git-send-email(1).
897
898       For hints on submission using the IMAP interface, see the EXAMPLE
899       section of git-imap-send(1).
900
901   Thunderbird
902       By default, Thunderbird will both wrap emails as well as flag them as
903       being format=flowed, both of which will make the resulting email
904       unusable by Git.
905
906       There are three different approaches: use an add-on to turn off line
907       wraps, configure Thunderbird to not mangle patches, or use an external
908       editor to keep Thunderbird from mangling the patches.
909
910       Approach #1 (add-on)
911           Install the Toggle Word Wrap add-on that is available from
912           https://addons.mozilla.org/thunderbird/addon/toggle-word-wrap/ It
913           adds a menu entry "Enable Word Wrap" in the composer’s "Options"
914           menu that you can tick off. Now you can compose the message as you
915           otherwise do (cut + paste, git format-patch | git imap-send, etc),
916           but you have to insert line breaks manually in any text that you
917           type.
918
919       Approach #2 (configuration)
920           Three steps:
921
922            1. Configure your mail server composition as plain text: Edit...
923               Account Settings...Composition & Addressing, uncheck "Compose
924               Messages in HTML".
925
926            2. Configure your general composition window to not wrap.
927
928               In Thunderbird 2: Edit..Preferences..Composition, wrap plain
929               text messages at 0
930
931               In Thunderbird 3: Edit..Preferences..Advanced..Config Editor.
932               Search for "mail.wrap_long_lines". Toggle it to make sure it is
933               set to false. Also, search for "mailnews.wraplength" and set
934               the value to 0.
935
936            3. Disable the use of format=flowed:
937               Edit..Preferences..Advanced..Config Editor. Search for
938               "mailnews.send_plaintext_flowed". Toggle it to make sure it is
939               set to false.
940
941           After that is done, you should be able to compose email as you
942           otherwise would (cut + paste, git format-patch | git imap-send,
943           etc), and the patches will not be mangled.
944
945       Approach #3 (external editor)
946           The following Thunderbird extensions are needed: AboutConfig from
947           http://aboutconfig.mozdev.org/ and External Editor from
948           http://globs.org/articles.php?lng=en&pg=8
949
950            1. Prepare the patch as a text file using your method of choice.
951
952            2. Before opening a compose window, use Edit→Account Settings to
953               uncheck the "Compose messages in HTML format" setting in the
954               "Composition & Addressing" panel of the account to be used to
955               send the patch.
956
957            3. In the main Thunderbird window, before you open the compose
958               window for the patch, use Tools→about:config to set the
959               following to the indicated values:
960
961                           mailnews.send_plaintext_flowed  => false
962                           mailnews.wraplength             => 0
963
964            4. Open a compose window and click the external editor icon.
965
966            5. In the external editor window, read in the patch file and exit
967               the editor normally.
968
969           Side note: it may be possible to do step 2 with about:config and
970           the following settings but no one’s tried yet.
971
972                       mail.html_compose                       => false
973                       mail.identity.default.compose_html      => false
974                       mail.identity.id?.compose_html          => false
975
976           There is a script in contrib/thunderbird-patch-inline which can
977           help you include patches with Thunderbird in an easy way. To use
978           it, do the steps above and then use the script as the external
979           editor.
980
981   KMail
982       This should help you to submit patches inline using KMail.
983
984        1. Prepare the patch as a text file.
985
986        2. Click on New Mail.
987
988        3. Go under "Options" in the Composer window and be sure that "Word
989           wrap" is not set.
990
991        4. Use Message → Insert file... and insert the patch.
992
993        5. Back in the compose window: add whatever other text you wish to the
994           message, complete the addressing and subject fields, and press
995           send.
996

BASE TREE INFORMATION

998       The base tree information block is used for maintainers or third party
999       testers to know the exact state the patch series applies to. It
1000       consists of the base commit, which is a well-known commit that is part
1001       of the stable part of the project history everybody else works off of,
1002       and zero or more prerequisite patches, which are well-known patches in
1003       flight that is not yet part of the base commit that need to be applied
1004       on top of base commit in topological order before the patches can be
1005       applied.
1006
1007       The base commit is shown as "base-commit: " followed by the 40-hex of
1008       the commit object name. A prerequisite patch is shown as
1009       "prerequisite-patch-id: " followed by the 40-hex patch id, which can be
1010       obtained by passing the patch through the git patch-id --stable
1011       command.
1012
1013       Imagine that on top of the public commit P, you applied well-known
1014       patches X, Y and Z from somebody else, and then built your three-patch
1015       series A, B, C, the history would be like:
1016
1017           ---P---X---Y---Z---A---B---C
1018
1019       With git format-patch --base=P -3 C (or variants thereof, e.g. with
1020       --cover-letter or using Z..C instead of -3 C to specify the range), the
1021       base tree information block is shown at the end of the first message
1022       the command outputs (either the first patch, or the cover letter), like
1023       this:
1024
1025           base-commit: P
1026           prerequisite-patch-id: X
1027           prerequisite-patch-id: Y
1028           prerequisite-patch-id: Z
1029
1030       For non-linear topology, such as
1031
1032           ---P---X---A---M---C
1033               \         /
1034                Y---Z---B
1035
1036       You can also use git format-patch --base=P -3 C to generate patches for
1037       A, B and C, and the identifiers for P, X, Y, Z are appended at the end
1038       of the first message.
1039
1040       If set --base=auto in cmdline, it will automatically compute the base
1041       commit as the merge base of tip commit of the remote-tracking branch
1042       and revision-range specified in cmdline. For a local branch, you need
1043       to make it to track a remote branch by git branch --set-upstream-to
1044       before using this option.
1045

EXAMPLES

1047       •   Extract commits between revisions R1 and R2, and apply them on top
1048           of the current branch using git am to cherry-pick them:
1049
1050               $ git format-patch -k --stdout R1..R2 | git am -3 -k
1051
1052       •   Extract all commits which are in the current branch but not in the
1053           origin branch:
1054
1055               $ git format-patch origin
1056
1057           For each commit a separate file is created in the current
1058           directory.
1059
1060       •   Extract all commits that lead to origin since the inception of the
1061           project:
1062
1063               $ git format-patch --root origin
1064
1065       •   The same as the previous one:
1066
1067               $ git format-patch -M -B origin
1068
1069           Additionally, it detects and handles renames and complete rewrites
1070           intelligently to produce a renaming patch. A renaming patch reduces
1071           the amount of text output, and generally makes it easier to review.
1072           Note that non-Git "patch" programs won’t understand renaming
1073           patches, so use it only when you know the recipient uses Git to
1074           apply your patch.
1075
1076       •   Extract three topmost commits from the current branch and format
1077           them as e-mailable patches:
1078
1079               $ git format-patch -3
1080

CAVEATS

1082       Note that format-patch will omit merge commits from the output, even if
1083       they are part of the requested range. A simple "patch" does not include
1084       enough information for the receiving end to reproduce the same merge
1085       commit.
1086

SEE ALSO

1088       git-am(1), git-send-email(1)
1089

GIT

1091       Part of the git(1) suite
1092
1093
1094
1095Git 2.39.1                        2023-01-13               GIT-FORMAT-PATCH(1)
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