blob: c0fd470da42991404c722f45ee7ac48cd774287b [file] [log] [blame]
git-format-patch - Prepare patches for e-mail submission
'git format-patch' [-k] [(-o|--output-directory) <dir> | --stdout]
[--no-thread | --thread[=<style>]]
[(--attach|--inline)[=<boundary>] | --no-attach]
[-s | --signoff]
[--signature=<signature> | --no-signature]
[-n | --numbered | -N | --no-numbered]
[--start-number <n>] [--numbered-files]
[--in-reply-to=Message-Id] [--suffix=.<sfx>]
[--subject-prefix=Subject-Prefix] [(--reroll-count|-v) <n>]
[--to=<email>] [--cc=<email>]
[--[no-]cover-letter] [--quiet] [--notes[=<ref>]]
[<common diff options>]
[ <since> | <revision range> ]
Prepare each commit with its patch in
one file per commit, formatted to resemble UNIX mailbox format.
The output of this command is convenient for e-mail submission or
for use with 'git am'.
There are two ways to specify which commits to operate on.
1. A single commit, <since>, specifies that the commits leading
to the tip of the current branch that are not in the history
that leads to the <since> to be output.
2. Generic <revision range> expression (see "SPECIFYING
REVISIONS" section in linkgit:gitrevisions[7]) means the
commits in the specified range.
The first rule takes precedence in the case of a single <commit>. To
apply the second rule, i.e., format everything since the beginning of
history up until <commit>, use the '\--root' option: `git format-patch
--root <commit>`. If you want to format only <commit> itself, you
can do this with `git format-patch -1 <commit>`.
By default, each output file is numbered sequentially from 1, and uses the
first line of the commit message (massaged for pathname safety) as
the filename. With the `--numbered-files` option, the output file names
will only be numbers, without the first line of the commit appended.
The names of the output files are printed to standard
output, unless the `--stdout` option is specified.
If `-o` is specified, output files are created in <dir>. Otherwise
they are created in the current working directory.
By default, the subject of a single patch is "[PATCH] " followed by
the concatenation of lines from the commit message up to the first blank
line (see the DISCUSSION section of linkgit:git-commit[1]).
When multiple patches are output, the subject prefix will instead be
"[PATCH n/m] ". To force 1/1 to be added for a single patch, use `-n`.
To omit patch numbers from the subject, use `-N`.
If given `--thread`, `git-format-patch` will generate `In-Reply-To` and
`References` headers to make the second and subsequent patch mails appear
as replies to the first mail; this also generates a `Message-Id` header to
:git-format-patch: 1
Prepare patches from the topmost <n> commits.
-o <dir>::
--output-directory <dir>::
Use <dir> to store the resulting files, instead of the
current working directory.
Name output in '[PATCH n/m]' format, even with a single patch.
Name output in '[PATCH]' format.
--start-number <n>::
Start numbering the patches at <n> instead of 1.
Output file names will be a simple number sequence
without the default first line of the commit appended.
Do not strip/add '[PATCH]' from the first line of the
commit log message.
Add `Signed-off-by:` line to the commit message, using
the committer identity of yourself.
Print all commits to the standard output in mbox format,
instead of creating a file for each one.
Create multipart/mixed attachment, the first part of
which is the commit message and the patch itself in the
second part, with `Content-Disposition: attachment`.
Disable the creation of an attachment, overriding the
configuration setting.
Create multipart/mixed attachment, the first part of
which is the commit message and the patch itself in the
second part, with `Content-Disposition: inline`.
Controls addition of `In-Reply-To` and `References` headers to
make the second and subsequent mails appear as replies to the
first. Also controls generation of the `Message-Id` header to
The optional <style> argument can be either `shallow` or `deep`.
'shallow' threading makes every mail a reply to the head of the
series, where the head is chosen from the cover letter, the
`--in-reply-to`, and the first patch mail, in this order. 'deep'
threading makes every mail a reply to the previous one.
The default is `--no-thread`, unless the 'format.thread' configuration
is set. If `--thread` is specified without a style, it defaults to the
style specified by 'format.thread' if any, or else `shallow`.
Beware that the default for 'git send-email' is to thread emails
itself. If you want `git format-patch` to take care of threading, you
will want to ensure that threading is disabled for `git send-email`.
Make the first mail (or all the mails with `--no-thread`) appear as a
reply to the given Message-Id, which avoids breaking threads to
provide a new patch series.
Do not include a patch that matches a commit in
<until>..<since>. This will examine all patches reachable
from <since> but not from <until> and compare them with the
patches being generated, and any patch that matches is
Instead of the standard '[PATCH]' prefix in the subject
line, instead use '[<Subject-Prefix>]'. This
allows for useful naming of a patch series, and can be
combined with the `--numbered` option.
-v <n>::
Mark the series as the <n>-th iteration of the topic. The
output filenames have `v<n>` pretended to them, and the
subject prefix ("PATCH" by default, but configurable via the
`--subject-prefix` option) has ` v<n>` appended to it. E.g.
`--reroll-count=4` may produce `v4-0001-add-makefile.patch`
file that has "Subject: [PATCH v4 1/20] Add makefile" in it.
Add a `To:` header to the email headers. This is in addition
to any configured headers, and may be used multiple times.
The negated form `--no-to` discards all `To:` headers added so
far (from config or command line).
Add a `Cc:` header to the email headers. This is in addition
to any configured headers, and may be used multiple times.
The negated form `--no-cc` discards all `Cc:` headers added so
far (from config or command line).
Use `ident` in the `From:` header of each commit email. If the
author ident of the commit is not textually identical to the
provided `ident`, place a `From:` header in the body of the
message with the original author. If no `ident` is given, use
the committer ident.
Note that this option is only useful if you are actually sending the
emails and want to identify yourself as the sender, but retain the
original author (and `git am` will correctly pick up the in-body
header). Note also that `git send-email` already handles this
transformation for you, and this option should not be used if you are
feeding the result to `git send-email`.
Add an arbitrary header to the email headers. This is in addition
to any configured headers, and may be used multiple times.
For example, `--add-header="Organization: git-foo"`.
The negated form `--no-add-header` discards *all* (`To:`,
`Cc:`, and custom) headers added so far from config or command
In addition to the patches, generate a cover letter file
containing the shortlog and the overall diffstat. You can
fill in a description in the file before sending it out.
Append the notes (see linkgit:git-notes[1]) for the commit
after the three-dash line.
The expected use case of this is to write supporting explanation for
the commit that does not belong to the commit log message proper,
and include it with the patch submission. While one can simply write
these explanations after `format-patch` has run but before sending,
keeping them as Git notes allows them to be maintained between versions
of the patch series (but see the discussion of the `notes.rewrite`
configuration options in linkgit:git-notes[1] to use this workflow).
Add a signature to each message produced. Per RFC 3676 the signature
is separated from the body by a line with '-- ' on it. If the
signature option is omitted the signature defaults to the Git version
Works just like --signature except the signature is read from a file.
Instead of using `.patch` as the suffix for generated
filenames, use specified suffix. A common alternative is
`--suffix=.txt`. Leaving this empty will remove the `.patch`
Note that the leading character does not have to be a dot; for example,
you can use `--suffix=-patch` to get `0001-description-of-my-change-patch`.
Do not print the names of the generated files to standard output.
Do not output contents of changes in binary files, instead
display a notice that those files changed. Patches generated
using this option cannot be applied properly, but they are
still useful for code review.
Treat the revision argument as a <revision range>, even if it
is just a single commit (that would normally be treated as a
<since>). Note that root commits included in the specified
range are always formatted as creation patches, independently
of this flag.
You can specify extra mail header lines to be added to each message,
defaults for the subject prefix and file suffix, number patches when
outputting more than one patch, add "To" or "Cc:" headers, configure
attachments, and sign off patches with configuration variables.
headers = "Organization: git-foo\n"
subjectprefix = CHANGE
suffix = .txt
numbered = auto
to = <email>
cc = <email>
attach [ = mime-boundary-string ]
signoff = true
coverletter = auto
The patch produced by 'git format-patch' is in UNIX mailbox format,
with a fixed "magic" time stamp to indicate that the file is output
from format-patch rather than a real mailbox, like so:
From 8f72bad1baf19a53459661343e21d6491c3908d3 Mon Sep 17 00:00:00 2001
From: Tony Luck <>
Date: Tue, 13 Jul 2010 11:42:54 -0700
Subject: [PATCH] =?UTF-8?q?[IA64]=20Put=20ia64=20config=20files=20on=20the=20?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
arch/arm config files were slimmed down using a python script
(See commit c2330e286f68f1c408b4aa6515ba49d57f05beae comment)
Do the same for ia64 so we can have sleek & trim looking
Typically it will be placed in a MUA's drafts folder, edited to add
timely commentary that should not go in the changelog after the three
dashes, and then sent as a message whose body, in our example, starts
with "arch/arm config files were...". On the receiving end, readers
can save interesting patches in a UNIX mailbox and apply them with
When a patch is part of an ongoing discussion, the patch generated by
'git format-patch' can be tweaked to take advantage of the 'git am
--scissors' feature. After your response to the discussion comes a
line that consists solely of "`-- >8 --`" (scissors and perforation),
followed by the patch with unnecessary header fields removed:
> So we should do such-and-such.
Makes sense to me. How about this patch?
-- >8 --
Subject: [IA64] Put ia64 config files on the Uwe Kleine-K├Ânig diet
arch/arm config files were slimmed down using a python script
When sending a patch this way, most often you are sending your own
patch, so in addition to the "`From $SHA1 $magic_timestamp`" marker you
should omit `From:` and `Date:` lines from the patch file. The patch
title is likely to be different from the subject of the discussion the
patch is in response to, so it is likely that you would want to keep
the Subject: line, like the example above.
Checking for patch corruption
Many mailers if not set up properly will corrupt whitespace. Here are
two common types of corruption:
* Empty context lines that do not have _any_ whitespace.
* Non-empty context lines that have one extra whitespace at the
One way to test if your MUA is set up correctly is:
* Send the patch to yourself, exactly the way you would, except
with To: and Cc: lines that do not contain the list and
maintainer address.
* Save that patch to a file in UNIX mailbox format. Call it a.patch,
* Apply it:
$ git fetch <project> master:test-apply
$ git checkout test-apply
$ git reset --hard
$ git am a.patch
If it does not apply correctly, there can be various reasons.
* The patch itself does not apply cleanly. That is _bad_ but
does not have much to do with your MUA. You might want to rebase
the patch with linkgit:git-rebase[1] before regenerating it in
this case.
* The MUA corrupted your patch; "am" would complain that
the patch does not apply. Look in the .git/rebase-apply/ subdirectory and
see what 'patch' file contains and check for the common
corruption patterns mentioned above.
* While at it, check the 'info' and 'final-commit' files as well.
If what is in 'final-commit' is not exactly what you would want to
see in the commit log message, it is very likely that the
receiver would end up hand editing the log message when applying
your patch. Things like "Hi, this is my first patch.\n" in the
patch e-mail should come after the three-dash line that signals
the end of the commit message.
Here are some hints on how to successfully submit patches inline using
various mailers.
GMail does not have any way to turn off line wrapping in the web
interface, so it will mangle any emails that you send. You can however
use "git send-email" and send your patches through the GMail SMTP server, or
use any IMAP email client to connect to the google IMAP server and forward
the emails through that.
For hints on using 'git send-email' to send your patches through the
GMail SMTP server, see the EXAMPLE section of linkgit:git-send-email[1].
For hints on submission using the IMAP interface, see the EXAMPLE
section of linkgit:git-imap-send[1].
By default, Thunderbird will both wrap emails as well as flag
them as being 'format=flowed', both of which will make the
resulting email unusable by Git.
There are three different approaches: use an add-on to turn off line wraps,
configure Thunderbird to not mangle patches, or use
an external editor to keep Thunderbird from mangling the patches.
Approach #1 (add-on)
Install the Toggle Word Wrap add-on that is available from
It adds a menu entry "Enable Word Wrap" in the composer's "Options" menu
that you can tick off. Now you can compose the message as you otherwise do
(cut + paste, 'git format-patch' | 'git imap-send', etc), but you have to
insert line breaks manually in any text that you type.
Approach #2 (configuration)
Three steps:
1. Configure your mail server composition as plain text:
Edit...Account Settings...Composition & Addressing,
uncheck "Compose Messages in HTML".
2. Configure your general composition window to not wrap.
In Thunderbird 2:
Edit..Preferences..Composition, wrap plain text messages at 0
In Thunderbird 3:
Edit..Preferences..Advanced..Config Editor. Search for
Toggle it to make sure it is set to `false`. Also, search for
"mailnews.wraplength" and set the value to 0.
3. Disable the use of format=flowed:
Edit..Preferences..Advanced..Config Editor. Search for
Toggle it to make sure it is set to `false`.
After that is done, you should be able to compose email as you
otherwise would (cut + paste, 'git format-patch' | 'git imap-send', etc),
and the patches will not be mangled.
Approach #3 (external editor)
The following Thunderbird extensions are needed:
AboutConfig from and
External Editor from
1. Prepare the patch as a text file using your method of choice.
2. Before opening a compose window, use Edit->Account Settings to
uncheck the "Compose messages in HTML format" setting in the
"Composition & Addressing" panel of the account to be used to
send the patch.
3. In the main Thunderbird window, 'before' you open the compose
window for the patch, use Tools->about:config to set the
following to the indicated values:
mailnews.send_plaintext_flowed => false
mailnews.wraplength => 0
4. Open a compose window and click the external editor icon.
5. In the external editor window, read in the patch file and exit
the editor normally.
Side note: it may be possible to do step 2 with
about:config and the following settings but no one's tried yet.
mail.html_compose => false
mail.identity.default.compose_html => false => false
There is a script in contrib/thunderbird-patch-inline which can help
you include patches with Thunderbird in an easy way. To use it, do the
steps above and then use the script as the external editor.
This should help you to submit patches inline using KMail.
1. Prepare the patch as a text file.
2. Click on New Mail.
3. Go under "Options" in the Composer window and be sure that
"Word wrap" is not set.
4. Use Message -> Insert file... and insert the patch.
5. Back in the compose window: add whatever other text you wish to the
message, complete the addressing and subject fields, and press send.
* Extract commits between revisions R1 and R2, and apply them on top of
the current branch using 'git am' to cherry-pick them:
$ git format-patch -k --stdout R1..R2 | git am -3 -k
* Extract all commits which are in the current branch but not in the
origin branch:
$ git format-patch origin
For each commit a separate file is created in the current directory.
* Extract all commits that lead to 'origin' since the inception of the
$ git format-patch --root origin
* The same as the previous one:
$ git format-patch -M -B origin
Additionally, it detects and handles renames and complete rewrites
intelligently to produce a renaming patch. A renaming patch reduces
the amount of text output, and generally makes it easier to review.
Note that non-Git "patch" programs won't understand renaming patches, so
use it only when you know the recipient uses Git to apply your patch.
* Extract three topmost commits from the current branch and format them
as e-mailable patches:
$ git format-patch -3
linkgit:git-am[1], linkgit:git-send-email[1]
Part of the linkgit:git[1] suite