threads / discuss / 6037

Question about commit message conventions

Subject: Question about commit message conventions

## tl;dr

6 messages between Oct 24, 2006 and Oct 25, 2006.

replies: 5people: 5as markdown or json

Tobias Toedter· Oct 24, 2006, 13:49 UTC · lore

Hi,

although I've read the documentation of git very carefully, I could not find anything related to certain commit message conventions. It would be great if someone here could explain a few things, maybe this could be added to the wiki afterwards (<http://git.or.cz/gitwiki/CommitMessageConventions>).

First of all, what's the intended use of the "Signed-off-by:" lines? Does it make sense to add my name there, even when I'm listed as the author or committer of a commit? I thought that they are intended mostly to note the approval of other developers.

On the other hand, concerning the approval of other developers, what's the difference between "Signed-off-by:" and "Acked-by:"? Are there any more "*-by:" fields that are in use?

Regards, Tobias

-- 
Tobias Toedter   | "I don't care to belong to a club that accepts people
Hamburg, Germany | like me as members." -- Groucho Marx

Jakub Narebski· Oct 24, 2006, 14:08 UTC · re: Tobias Toedter · lore

Re: Question about commit message conventions

Tobias Toedter wrote:

Show 15 quoted lines

> Hi,
> 
> although I've read the documentation of git very carefully, I could not find 
> anything related to certain commit message conventions. It would be great 
> if someone here could explain a few things, maybe this could be added to 
> the wiki afterwards (<http://git.or.cz/gitwiki/CommitMessageConventions>).
> 
> First of all, what's the intended use of the "Signed-off-by:" lines? Does it 
> make sense to add my name there, even when I'm listed as the author or 
> committer of a commit? I thought that they are intended mostly to note the 
> approval of other developers.
> 
> On the other hand, concerning the approval of other developers, what's the 
> difference between "Signed-off-by:" and "Acked-by:"? Are there any 
> more "*-by:" fields that are in use?

>From Documentation/SubmittingPatches:

(6) Sign your work [...] The sign-off is a simple line at the end of the explanation for the patch, which certifies that you wrote it or otherwise have the right to pass it on as a open-source patch.

"Acked-by:" is used to notify that patch was accepted by somebody, which usually is maintainer of part affected by patch.

I have seen exactly on "Cheered-on-by:", and there are probably some "Noticed-by:" there.

-- 
Jakub Narebski
Warsaw, Poland
ShadeHawk on #git

Tobias Toedter· Oct 24, 2006, 14:14 UTC · re: Jakub Narebski · lore

Re: Question about commit message conventions

On Tuesday 24 October 2006 16:08, Jakub Narebski wrote:

> Tobias Toedter wrote:
> > although I've read the documentation of git very carefully

[...]

> From Documentation/SubmittingPatches:

D'oh! Thanks.

Regards, Tobias

-- 
Tobias Toedter   | "I don't care to belong to a club that accepts people
Hamburg, Germany | like me as members." -- Groucho Marx

Erik Mouw· Oct 24, 2006, 14:08 UTC · re: Tobias Toedter · lore

Re: Question about commit message conventions

On Tue, Oct 24, 2006 at 03:49:44PM +0200, Tobias Toedter wrote:

Show 9 quoted lines

> although I've read the documentation of git very carefully, I could not find 
> anything related to certain commit message conventions. It would be great 
> if someone here could explain a few things, maybe this could be added to 
> the wiki afterwards (<http://git.or.cz/gitwiki/CommitMessageConventions>).
> 
> First of all, what's the intended use of the "Signed-off-by:" lines? Does it 
> make sense to add my name there, even when I'm listed as the author or 
> committer of a commit? I thought that they are intended mostly to note the 
> approval of other developers.

See Documentation/SubmittingPatches. You basically say you have the right to submit the patch.

> On the other hand, concerning the approval of other developers, what's the 
> difference between "Signed-off-by:" and "Acked-by:"? Are there any 
> more "*-by:" fields that are in use?

Acked-by is usually used when someone (not the upstream maintainer the patch was send to) agrees with the patch. I.e.: (s)he says the content of the patch is OK without actually acknowledging something about the right to submit.

Erik

-- 
+-- Erik Mouw -- www.harddisk-recovery.com -- +31 70 370 12 90 --
| Lab address: Delftechpark 26, 2628 XH, Delft, The Netherlands

Andreas Ericsson· Oct 25, 2006, 15:23 UTC · re: Erik Mouw · lore

Re: Question about commit message conventions

Erik Mouw wrote:

Show 11 quoted lines

> On Tue, Oct 24, 2006 at 03:49:44PM +0200, Tobias Toedter wrote:
> 
>> On the other hand, concerning the approval of other developers, what's the 
>> difference between "Signed-off-by:" and "Acked-by:"? Are there any 
>> more "*-by:" fields that are in use?
> 
> Acked-by is usually used when someone (not the upstream maintainer the
> patch was send to) agrees with the patch. I.e.: (s)he says the content
> of the patch is OK without actually acknowledging something about the
> right to submit.
>

If you sift through the Linux kernel, you will find numerous patches where subsystem maintainers have acked patches sent to them. I *think* this usually means that they have reviewed the patch and approve of it, but not modified it. The Ack is then solely for Linus' benefits and tells him that at least one pair of eyes have already gone over the patch.

Subsys maintainers sometimes also add Signed-off-by: lines, which I assume means they have tweaked the patch somewhat or somehow collaborated with the author in producing it. I know Junio signs off patches he modifies, and I'm guessing this habit is inherited from the kernel workflow which was most likely encouraged by Linus when he was the Git maintainer.

Lots of guesswork here, but in a sane world I can't be too far off the mark ;-)

-- 
Andreas Ericsson                   andreas.ericsson@op5.se
OP5 AB                             www.op5.se

Junio C Hamano· Oct 25, 2006, 18:48 UTC · re: Andreas Ericsson · lore

Re: Question about commit message conventions

Andreas Ericsson <ae@op5.se> writes:

Show 6 quoted lines

> If you sift through the Linux kernel, you will find numerous patches
> where subsystem maintainers have acked patches sent to them. I *think*
> this usually means that they have reviewed the patch and approve of
> it, but not modified it. The Ack is then solely for Linus' benefits
> and tells him that at least one pair of eyes have already gone over
> the patch.

Correct.

Show 6 quoted lines

> Subsys maintainers sometimes also add Signed-off-by: lines, which I
> assume means they have tweaked the patch somewhat or somehow
> collaborated with the author in producing it.
>...
> Lots of guesswork here, but in a sane world I can't be too far off the
> mark ;-)

Documentation/SubmittingPatches makes it unnecessary to make any guesses on S-o-b lines. Regarding subsystem maintainer sign-offs, you are referring to DCO 1.1 (b), but the signature could have been made under DCO 1.1 (c).

In plain terms, the signer vouches that the patch was passed either intact or with modifications but the original and modifications are both releasable, to the best of signer's knowledge, under open source terms.