breaking long header lines into 2 (or more) lines

[Matthias Apitz]

Hello,

Long header lines can be split into 2 or more lines and the 2nd line
must start with a blank (is TAB allowed too). Is there any rule (RFC) at
which char the split is allowed or not allowed? For example, can mail
addr lines be broken at any point like this one:

To: mutt-***@mut
t.org

I did tests before asking and such a case like the one with mutt-***@mutt.org
above is arriving fine and the line is put together somewhere in the MTA
chain.

Thanks for any pointer?

matthias

[Darac Marjal]

Post by Matthias Apitz
Hello,
Long header lines can be split into 2 or more lines and the 2nd line
must start with a blank (is TAB allowed too). Is there any rule (RFC) at
which char the split is allowed or not allowed? For example, can mail
t.org
above is arriving fine and the line is put together somewhere in the MTA
chain.

RFC 5322 (which obsoletes RFC2822, which obsoletes RFC822) defines the
format of "Internet Messages" (i.e. e-mails). The relevant section of it
is section 2.2.3 "Long Header Fields"
https://tools.ietf.org/html/rfc5322#section-2.2.3

2.2.3. Long Header Fields

Each header field is logically a single line of characters comprising
the field name, the colon, and the field body. For convenience
however, and to deal with the 998/78 character limitations per line,
the field body portion of a header field can be split into a
multiple-line representation; this is called "folding". The general
rule is that wherever this specification allows for folding white
space (not simply WSP characters), a CRLF may be inserted before any
WSP.

For example, the header field:

Subject: This is a test

can be represented as:

Subject: This
is a test

Note: Though structured field bodies are defined in such a way
that folding can take place between many of the lexical tokens
(and even within some of the lexical tokens), folding SHOULD be
limited to placing the CRLF at higher-level syntactic breaks. For
instance, if a field body is defined as comma-separated values, it
is recommended that folding occur after the comma separating the
structured items in preference to other places where the field
could be folded, even if it is allowed elsewhere.

The process of moving from this folded multiple-line representation
of a header field to its single line representation is called
"unfolding". Unfolding is accomplished by simply removing any CRLF
that is immediately followed by WSP. Each header field should be
treated in its unfolded form for further syntactic and semantic
evaluation. An unfolded header field has no length restriction and
therefore may be indeterminately long.

Post by Matthias Apitz
Thanks for any pointer?
matthias
--
Public GnuPG key: http://www.unixarea.de/key.pub

[Ian Zimmerman]

Post by Matthias Apitz
Long header lines can be split into 2 or more lines and the 2nd line
must start with a blank (is TAB allowed too). Is there any rule (RFC)
at which char the split is allowed or not allowed? For example, can
t.org
I did tests before asking and such a case like the one with
together somewhere in the MTA chain.

That is odd, it shouldn't work. According to the RFC cited elsewhere in
thread.

[Matthias Apitz]

Post by Ian Zimmerman
That is odd, it shouldn't work. According to the RFC cited elsewhere in
thread.
--
Please don't Cc: me privately on mailing lists and Usenet,
if you also post the followup to the list or newsgroup.
To reply privately _only_ on Usenet and on broken lists
which rewrite From, fetch the TXT record for no-use.mooo.com.

Hmmm? You Cc'ed me :-)

matthias

[Ian Zimmerman]

Post by Matthias Apitz

Please don't Cc: me privately on mailing lists and Usenet, if you
also post the followup to the list or newsgroup. To reply privately
_only_ on Usenet and on broken lists which rewrite From, fetch the
TXT record for no-use.mooo.com.

Hmmm? You Cc'ed me :-)

Sorry about that, but it is because the list is of the munging variety
(namely, it adds a Reply-To header). I refuse to spend energy
compensating for that borkage.

Unless you did that yourself, of course - but I'm giving you the benefit
of the doubt ;-)

[Patrick Shanahan]

Post by Ian Zimmerman

Post by Matthias Apitz

Please don't Cc: me privately on mailing lists and Usenet, if you
also post the followup to the list or newsgroup. To reply privately
_only_ on Usenet and on broken lists which rewrite From, fetch the
TXT record for no-use.mooo.com.

Hmmm? You Cc'ed me :-)

Sorry about that, but it is because the list is of the munging variety
(namely, it adds a Reply-To header). I refuse to spend energy
compensating for that borkage.
Unless you did that yourself, of course - but I'm giving you the benefit
of the doubt ;-)

which he did and does regularily:
"Mail-Followup-To: Matthias Apitz <***@unixarea.de>,
mutt-***@mutt.org"

[Matthias Apitz]

On Wednesday, 25 April 2018 17:17:54 CEST, Patrick Shanahan

Post by Ian Zimmerman

Post by Matthias Apitz

Please don't Cc: me privately on mailing lists and Usenet, if you
also post the followup to the list or newsgroup. To reply privately
_only_ on Usenet and on broken lists which rewrite From, fetch the
TXT record for no-use.mooo.com.

Hmmm? You Cc'ed me :-)

Sorry about that, but it is because the list is of the munging variety
(namely, it adds a Reply-To header). I refuse to spend energy
compensating for that borkage.
Unless you did that yourself, of course - but I'm giving you the benefit
of the doubt ;-)

I do not set this in my mutt.

mstthias

[Kevin J. McCarthy]

Post by Matthias Apitz
On Wednesday, 25 April 2018 17:17:54 CEST, Patrick Shanahan
I do not set this in my mutt.

Try adding mutt-users to your 'subscribe' lists, instead of 'lists'.

[Matthias Apitz]

Post by Kevin J. McCarthy

Post by Matthias Apitz
On Wednesday, 25 April 2018 17:17:54 CEST, Patrick Shanahan
I do not set this in my mutt.

Try adding mutt-users to your 'subscribe' lists, instead of 'lists'.

Kind of thread drift, but I actually wonder if Mutt shouldn't move away
from Mail-Followup-To, as it never became a standard, and is not really
adopted by (m)any other commonly used mail clients.
w

$ grep mutt-users ~/.muttrc
send-hook mutt-***@mutt.org 'my_hdr From: Matthias Apitz <***@unixarea.de>'
send-hook mutt-***@mutt.org 'my_hdr Reply-To: Matthias Apitz <***@unixarea.de>'
lists asterisk-***@lists.digium.com biblio-***@yahoogrupos.com.mx ***@berklix.org ***@lists.openmoko.org digikam-***@kde.org ekiga-devel-***@gnome.org ekiga-***@gnome.org enlightenment-***@lists.sourceforge.net fgcuba-muc-***@listen.einewelthaus.de freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org freebsd-***@freebsd.org ***@es.freebsd.org gnomemeeting-***@gnome.org gphoto-***@lists.sourceforge.net gpsd-***@lists.berlios.de kde-***@freebsd.kde.org kde-***@kde.org l-***@glove.org.ve linux-***@listas.softwarelibre.cu evolution-***@gnome.org local-openmoko-***@projects.openmoko.org mplayer-***@mplayerhq.hu mutt-***@mutt.org openmoko-***@lists.openmoko.org ubuntu-***@lists.launchpad.net betatesters-***@bq.com chromium-os-***@chromium.org ***@freebsd.org gnupg-***@gnupg.org

$ grep -i Mail-Followup-To ~/.muttrc
$

as I said, I do not set any Mail-Followup-To; and I think Reply-To:
and From: is quite normal;

matthias

[Patrick Shanahan]

Post by Matthias Apitz

Post by Kevin J. McCarthy

Post by Matthias Apitz
On Wednesday, 25 April 2018 17:17:54 CEST, Patrick Shanahan
I do not set this in my mutt.

Try adding mutt-users to your 'subscribe' lists, instead of 'lists'.

Kind of thread drift, but I actually wonder if Mutt shouldn't move away
from Mail-Followup-To, as it never became a standard, and is not really
adopted by (m)any other commonly used mail clients.
w

$ grep mutt-users ~/.muttrc
$ grep -i Mail-Followup-To ~/.muttrc
$
and From: is quite normal;

then you have someone in your system makeing changes to your posts,

<quote>
Date: Wed, 25 Apr 2018 19:31:20 +0200
From: Matthias Apitz <***@unixarea.de>
To: mutt-***@mutt.org
Subject: Re: Mail-Followup-To (was Re: breaking long header lines into 2 (or more)
lines)
X-Spam-Level:
X-Spam-Status: No
X-Original-To: paka
X-Original-To: mutt-***@mutt.org
Mail-Followup-To: Matthias Apitz <***@unixarea.de>, mutt-***@mutt.org
User-Agent: Mutt/1.5.24 (2015-08-30)
Reply-To: Matthias Apitz <***@unixarea.de>
X-Envelope-From: mutt-users-***@mutt.org
Lines: 57
</quote>

[Matthias Apitz]

Post by Patrick Shanahan
then you have someone in your system makeing changes to your posts,

the 'system' is a FreeBSD netbook using mutt+sendmail;

I will Cc me on this mail to see its sent headers;

matthias

[Matthias Apitz]

Post by Matthias Apitz

Post by Patrick Shanahan
then you have someone in your system makeing changes to your posts,

the 'system' is a FreeBSD netbook using mutt+sendmail;
I will Cc me on this mail to see its sent headers;

The outgoing mails contains a header line:

Mail-Followup-To: Matthias Apitz <***@unixarea.de>, mutt-***@mutt.org

Who adds this? mutt by its own? If so, based on what?

matthias

[Patrick Shanahan]

Post by Matthias Apitz

Post by Matthias Apitz

Post by Patrick Shanahan
then you have someone in your system makeing changes to your posts,

the 'system' is a FreeBSD netbook using mutt+sendmail;
I will Cc me on this mail to see its sent headers;

Who adds this? mutt by its own? If so, based on what?

you do, don't you have man pages for mutt and muttrc? mutt doesn't do
anything except what *you* tell it to.

[Matthias Apitz]

Post by Patrick Shanahan

Post by Matthias Apitz
Who adds this? mutt by its own? If so, based on what?

you do, don't you have man pages for mutt and muttrc? mutt doesn't do
anything except what *you* tell it to.

no, mutt does it by its own because the default of 'followup_to' is yes; IMHO it
should be changed to 'no'.

matthias

[Patrick Shanahan]

Post by Matthias Apitz

Post by Patrick Shanahan

Post by Matthias Apitz
Who adds this? mutt by its own? If so, based on what?

you do, don't you have man pages for mutt and muttrc? mutt doesn't do
anything except what *you* tell it to.

no, mutt does it by its own because the default of 'followup_to' is yes; IMHO it
should be changed to 'no'.

you are but one person and mutt has been around > 20 years and defaults
modified to fit a majority. perhaps you can make a compelling case to
change the default. but if *you* want it different, you will have to
campaign for the change.

usually when one begins to use an application, they make an effort to set
the parameters to fit their style. you apparently have not felt the
necessity to do so, past claiming the application was doing something you
did not set it to. which you have found was incorrect.

did you look at the defaults before using mutt?

[Matthias Apitz]

I'm tired of such blames. I'm using mutt for more then 15
years, IIRC. And of course every day you learn something new or
something I did wrong. But what you send is not help, but just
blames.

Thanks

matthias

[Matthias Apitz]

you might want to reconsider. you said *you* didn't make the setting,
that "mutt" was to blame. there really is no "blame". one must make the
settings to do what they wish and you didn't bother and now try to divert
the responsibility.

Wrong. There a good and bad defaults. And the default for follow_up
policy is just bad because it does, as you see in my case, things that
the user newer wanted and not even was aware of.

make the correct settings and you will get what you wish.
btw, it is not corrected yet.

I know. But I have not had time to think what exactly I will change.

matthias

[Todd Zullinger]

Post by Matthias Apitz

Post by Matthias Apitz

Post by Patrick Shanahan
then you have someone in your system makeing changes to your posts,

the 'system' is a FreeBSD netbook using mutt+sendmail;
I will Cc me on this mail to see its sent headers;

Who adds this? mutt by its own? If so, based on what?

Quoting http://mutt.org/doc/manual/#followup-to

3.72. followup_to

Type: boolean
Default: yes

Controls whether or not the “Mail-Followup-To:” header
field is generated when sending mail. When set, Mutt
will generate this field when you are replying to a
known mailing list, specified with the “subscribe” or
“lists” commands.

This field has two purposes. First, preventing you from
receiving duplicate copies of replies to messages which
you send to mailing lists, and second, ensuring that you
do get a reply separately for any messages sent to known
lists to which you are not subscribed.

The header will contain only the list's address for
subscribed lists, and both the list address and your own
email address for unsubscribed lists. Without this
header, a group reply to your message sent to a
subscribed list will be sent to both the list and your
address, resulting in two copies of the same email for
you.

That's why Kevin suggested setting 'subscribe' for the mutt
list in your config.

The 'honor_followup_to' variable is related, relevant for
mutt users replying to messages with a 'Mail-Follup-To:'
header.

[Kevin J. McCarthy]

Post by Matthias Apitz

Post by Kevin J. McCarthy

Post by Matthias Apitz
On Wednesday, 25 April 2018 17:17:54 CEST, Patrick Shanahan
I do not set this in my mutt.

Try adding mutt-users to your 'subscribe' lists, instead of 'lists'.

^^^^^^^^^ ^^^^^
^^^^^^^^^
For mailing lists that you are subscribed to, you should use the
'subscribe' command, not the 'lists' command.

Post by Matthias Apitz
$ grep mutt-users ~/.muttrc

Try changing the above line to use the 'subscribe' command (or at least
move mutt-***@mutt.org to a separate 'subscribe' command if you aren't
subscribed to all of those). Otherwise Mutt is interpreting it as a
mailing list, but not one that you are subscribed too, and is adding
your address in the Mail-Followup-To header.

[Derek Martin]

Post by Matthias Apitz
$ grep -i Mail-Followup-To ~/.muttrc
$
and From: is quite normal;

Reply-To should normally not be set; its purpose is to route mail to
the proper address where you will receive it, in the event that your
outgoing mail server or other piece of software munges the From
address when you send mail, or similar. This is pretty rare these
days but was once more common. There are other uses but they're all
basically the same: you want replies to go to a different address than
the one in the From header. In most cases your From address should be
the same as the address you receive mail at, and thus there's no
reason to set reply-to.

You can of course set it anyway, and usually it will have no effect;
but if you do so it's possible that you may interfere with other
software that has good reason to modify Reply-To on your behalf.
This, too, is rare these days.

[Matthias Apitz]

Post by Derek Martin

Post by Matthias Apitz
$ grep -i Mail-Followup-To ~/.muttrc
$
and From: is quite normal;

Reply-To should normally not be set; its purpose is to route mail to
the proper address where you will receive it, in the event that your
...

Hmm, someone set Reply-To in the headers of your mail too.

matthias

[Ian Zimmerman]

Post by Matthias Apitz
Hmm, someone set Reply-To in the headers of your mail too.

That was the list manager, and that's what I call munging. AIUI it was
one of the reasons why Mail-Followup-To was invented, because Reply-To
could not be trusted anymore. I feel it would be better to stop working
around the borkage of munging lists and expose it fully, maybe then the
practice would stop at least on geeky lists such as this one.

[Kevin J. McCarthy]

Post by Ian Zimmerman

Post by Matthias Apitz
Hmm, someone set Reply-To in the headers of your mail too.

That was the list manager, and that's what I call munging.

I don't believe so. I have reply_goes_to_list set to 'Poster', which is
not supposed to add (or remove) any such header.

[Patrick Shanahan]

Post by Kevin J. McCarthy

Post by Ian Zimmerman

Post by Matthias Apitz
Hmm, someone set Reply-To in the headers of your mail too.

That was the list manager, and that's what I call munging.

I don't believe so. I have reply_goes_to_list set to 'Poster', which is
not supposed to add (or remove) any such header.

yes, Mail-Followup-To, is set to list addr and Reply-To is empty.

[Derek Martin]

Post by Matthias Apitz

Post by Derek Martin

Post by Matthias Apitz
$ grep -i Mail-Followup-To ~/.muttrc
$
and From: is quite normal;

Reply-To should normally not be set; its purpose is to route mail to
the proper address where you will receive it, in the event that your
...

Hmm, someone set Reply-To in the headers of your mail too.

Yes, I do set it, because the address I post from is not valid (see my
sig). If you want to reply to one of my list posts your only option
is to reply to the list. Or, actually it's not that hard to figure
out how to e-mail me directly, if you're paying attention, but the
point is robots are very unlikly to succeed at that... including your
mailer's reply function.

[I tend to think list conversations should stay on the list anyway,
BUT ordinarily the list should not take the option away from the
sender... only the receiver should have that privilege, via reply-to.]

[Ian Zimmerman]

Kind of thread drift, but I actually wonder if Mutt shouldn't move
away from Mail-Followup-To, as it never became a standard, and is not
really adopted by (m)any other commonly used mail clients.

It is supported by Gnus. I don't know of any others, and I wonder the
same thing, because it seems to create at least some mischief.

Kevin, please do the evangelist thing now ;-)

[Mihai Lazarescu]

Post by Ian Zimmerman

Kind of thread drift, but I actually wonder if Mutt shouldn't move
away from Mail-Followup-To, as it never became a standard, and is

not

really adopted by (m)any other commonly used mail clients.

It is supported by Gnus. I don't know of any others, and I wonder the
same thing, because it seems to create at least some mischief.

Seems also supported by Thunderbird https://wiki.mozilla.org/Thunderbird:Help_Documentation:Mail-Followup-To_and_Mail-Reply-To and Roundcube https://github.com/roundcube/roundcubemail/issues/1937

Mihai

[Kevin J. McCarthy]

Post by Mihai Lazarescu

Post by Ian Zimmerman

Kind of thread drift, but I actually wonder if Mutt shouldn't move
away from Mail-Followup-To, as it never became a standard, and is

not

really adopted by (m)any other commonly used mail clients.

It is supported by Gnus. I don't know of any others, and I wonder the
same thing, because it seems to create at least some mischief.

Seems also supported by Thunderbird https://wiki.mozilla.org/Thunderbird:Help_Documentation:Mail-Followup-To_and_Mail-Reply-To and Roundcube https://github.com/roundcube/roundcubemail/issues/1937

I always thought $followup_to was a pretty nice feature. While I
sympathize with Matthias, the mischief was the result of
misconfiguration, and Mutt requires nothing if not attention to the
documentation and configuration.

However, if there is a strong majority of mutt-users subscribers that
agree with $followup_to defaulting to 'no', I'll make the change.

[Patrick Shanahan]

* Kevin J. McCarthy <***@8t8.us> [04-27-18 11:58]:
[...]

Post by Kevin J. McCarthy
I always thought $followup_to was a pretty nice feature. While I
sympathize with Matthias, the mischief was the result of
misconfiguration, and Mutt requires nothing if not attention to the
documentation and configuration.
However, if there is a strong majority of mutt-users subscribers that
agree with $followup_to defaulting to 'no', I'll make the change.

I have no problem with the present status and have not in last 15 years or
so.

[Erik Christiansen]

Post by Kevin J. McCarthy
I always thought $followup_to was a pretty nice feature. While I
sympathize with Matthias, the mischief was the result of
misconfiguration, and Mutt requires nothing if not attention to the
documentation and configuration.
However, if there is a strong majority of mutt-users subscribers that
agree with $followup_to defaulting to 'no', I'll make the change.

Here, <F1> declares: "Mutt also supports the Mail-Followup-To header.
When you send a message to a list of recipients which includes one or
several subscribed mailing lists, and if the $followup_to option is set,
Mutt will generate a Mail-Followup-To header which contains all the
recipients to whom you send this message, but not your address."

The request for a changed default seems to have arisen from Matthias'
Mail-Followup-To header erroneously including his own address. It does
seem likely that this problem arises from misconfiguration, as no-one
shares his difficulties. Here I have both subscribed lists, and some not.
In the latter case, Mail-Followup-To is not generated, and in the former
I find only the other recipients, as described in the manual. That is
with no $followup_to setting, i.e. default, as Matthias has.

What other configuration is required in order to place the sender's
address in Mail-Followup-To, in contradiction to the manual entry is
then a curiosity.

Erik

[Kevin J. McCarthy]

Post by Erik Christiansen
Here, <F1> declares: "Mutt also supports the Mail-Followup-To header.
When you send a message to a list of recipients which includes one or
several subscribed mailing lists, and if the $followup_to option is set,
Mutt will generate a Mail-Followup-To header which contains all the
recipients to whom you send this message, but not your address."

The key word above is "subscribed". And this is what distinguishes the
"subscribe" command from the "lists" command.

The documentation for $followup_to further elaborates:
The header will contain only the list's address for subscribed lists,
and both the list address and your own email address for unsubscribed
lists.

So, using the "subscribe" command will generate only the list address in
the MFT header. Using the "lists" command will generate both the list
address and your own email address.

The fact that this has tripped up at least a couple long-time users
means the documentation is not clear enough about this. I'll add
something to the "Handling Mailing Lists" section to help clarify this.

[Derek Martin]

Post by Kevin J. McCarthy
I always thought $followup_to was a pretty nice feature. While I
sympathize with Matthias, the mischief was the result of
misconfiguration, and Mutt requires nothing if not attention to the
documentation and configuration.

I agree strongly with this point. Moreover, it's reasonable to
presume that anyone subscribed to this list uses Mutt (at least some
of the time), and as such have access to features that make good use
of the header. So there's arguably at least some value in keeping it.

Post by Kevin J. McCarthy
However, if there is a strong majority of mutt-users subscribers that
agree with $followup_to defaulting to 'no', I'll make the change.

I think it's a nice idea too, but the draft (which expired 20 years ago)
never became a standard.
I'd argue that if one of Mutt's claims to fame is standards-compliance,
dropping support for it or not defaulting it to on might be the better
option.

I would (amiably!) argue that's nonsense, as illustrated by my
favorite anti-example of standards compliance: The removal of tail
-[number] from the tail command. It broke millions of shell scripts,
and the gnu binutils maintainers were essentially forced to put it
back in (albeit much too late for most people who were impacted),
despite it being deprecated by the standard.

The lesson should be this: Standards compliance != removal of
additional useful features not specified by the standards. And as a
corollary, standards which forbid useful features without compelling
reason should be ignored.