unofficial mirror of bug-gnu-emacs@gnu.org 
 help / color / mirror / code / Atom feed
* bug#46236: 26.1; explicit the info files installation
@ 2021-02-01 14:10 marmot-te
  2021-02-03  5:48 ` Richard Stallman
  2021-03-06 14:25 ` Tomas Nordin
  0 siblings, 2 replies; 17+ messages in thread
From: marmot-te @ 2021-02-01 14:10 UTC (permalink / raw)
  To: 46236


Hello,

It is a common issue for many new emacs users to figure out how to 
get the info files for emacs, for its packages, and eventually for 
others systems packages. Somes probably never figures it out.

It is indeed sad since we all need theses nices info files.

I suggest to add a notice in the info/dir file itself (or at least 
an info link easy to notice, be it to the FAQ or not) that 
explicit that you probably need to install system-wise :
- extra documentations packages such as bash-doc, 
  emacs-common-non-dfsg (non-free repository for debian). 
- ensure texinfo is installed in order to compile documentation 
  when new emacs packages are installed.

Another step may be to trigger a message when an user type "C-h 
RET" and there is no "emacs the editor" manual (so obviously the 
user does not have the info files installed when he is asking for 
it).

I already write about this subject here :
https://teddit.net/r/emacs/comments/jm4e0k/rtfm_quest_or_the_info_files_like_it_was_supposed/

I know this is specific since it probably only affect debian / 
fedora & derivatives users but I have no idea to what are the 
steps for the OS to find and install others info files.

-- 
<:3nn~~
   <:3nn~~
      <:3nn~~





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-02-01 14:10 bug#46236: 26.1; explicit the info files installation marmot-te
@ 2021-02-03  5:48 ` Richard Stallman
  2021-04-21  3:20   ` Stefan Kangas
  2021-03-06 14:25 ` Tomas Nordin
  1 sibling, 1 reply; 17+ messages in thread
From: Richard Stallman @ 2021-02-03  5:48 UTC (permalink / raw)
  To: marmot-te; +Cc: 46236

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > I suggest to add a notice in the info/dir file itself (or at least 
  > an info link easy to notice, be it to the FAQ or not) that 
  > explicit that you probably need to install system-wise :
  > - extra documentations packages such as bash-doc, 
  >   emacs-common-non-dfsg (non-free repository for debian). 
  > - ensure texinfo is installed in order to compile documentation 
  >   when new emacs packages are installed.

In principle this is desirable, but it may be complex.  For instance,
on various GNU/Linux distros the method is different.

-- 
Dr Richard Stallman
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)







^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-02-01 14:10 bug#46236: 26.1; explicit the info files installation marmot-te
  2021-02-03  5:48 ` Richard Stallman
@ 2021-03-06 14:25 ` Tomas Nordin
  2021-03-07  6:11   ` Richard Stallman
  1 sibling, 1 reply; 17+ messages in thread
From: Tomas Nordin @ 2021-03-06 14:25 UTC (permalink / raw)
  To: marmot-te, 46236

marmot-te <marmot-te@riseup.net> writes:

> Hello,
>
> It is a common issue for many new emacs users to figure out how to 
> get the info files for emacs, for its packages, and eventually for 
> others systems packages. Somes probably never figures it out.
>
> It is indeed sad since we all need theses nices info files.
>
> I suggest to add a notice in the info/dir file itself (or at least 
> an info link easy to notice, be it to the FAQ or not) that 
> explicit that you probably need to install system-wise :
> - extra documentations packages such as bash-doc, 
>   emacs-common-non-dfsg (non-free repository for debian). 
> - ensure texinfo is installed in order to compile documentation 
>   when new emacs packages are installed.

Ever since I discovered this issue I have been curious if this (somewhat
tragicomic) split in interpretation of what is free documentation will
be resolved some day. 

It has the effect that GFDL documentation will have to be installed from
Debian non-free archives. The ease of such installations seem to be the
sole reason Debian is not an endorsed Gnu/Linux distro by the FSF.

--
Tomas





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-03-06 14:25 ` Tomas Nordin
@ 2021-03-07  6:11   ` Richard Stallman
  0 siblings, 0 replies; 17+ messages in thread
From: Richard Stallman @ 2021-03-07  6:11 UTC (permalink / raw)
  To: Tomas Nordin; +Cc: marmot-te, 46236

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

I think it is a shame Debian took that position, and I hope
they change it.

-- 
Dr Richard Stallman
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)







^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-02-03  5:48 ` Richard Stallman
@ 2021-04-21  3:20   ` Stefan Kangas
  2021-04-21  9:02     ` Eli Zaretskii
  0 siblings, 1 reply; 17+ messages in thread
From: Stefan Kangas @ 2021-04-21  3:20 UTC (permalink / raw)
  To: Richard Stallman; +Cc: marmot-te, 46236

Richard Stallman <rms@gnu.org> writes:

>   > I suggest to add a notice in the info/dir file itself (or at least
>   > an info link easy to notice, be it to the FAQ or not) that
>   > explicit that you probably need to install system-wise :
>   > - extra documentations packages such as bash-doc,
>   >   emacs-common-non-dfsg (non-free repository for debian).
>   > - ensure texinfo is installed in order to compile documentation
>   >   when new emacs packages are installed.
>
> In principle this is desirable, but it may be complex.  For instance,
> on various GNU/Linux distros the method is different.

Let's assume for the sake of argument that we only want to do this for
Debian and derivatives.  That would require adding the non-free
repository, thus indirectly encouraging users to use proprietary
software.  Is that something we really would want to do?





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21  3:20   ` Stefan Kangas
@ 2021-04-21  9:02     ` Eli Zaretskii
  2021-04-21 12:06       ` Stefan Kangas
  0 siblings, 1 reply; 17+ messages in thread
From: Eli Zaretskii @ 2021-04-21  9:02 UTC (permalink / raw)
  To: Stefan Kangas; +Cc: marmot-te, 46236, rms

> From: Stefan Kangas <stefan@marxist.se>
> Date: Tue, 20 Apr 2021 22:20:03 -0500
> Cc: marmot-te <marmot-te@riseup.net>, 46236@debbugs.gnu.org
> 
> Richard Stallman <rms@gnu.org> writes:
> 
> >   > I suggest to add a notice in the info/dir file itself (or at least
> >   > an info link easy to notice, be it to the FAQ or not) that
> >   > explicit that you probably need to install system-wise :
> >   > - extra documentations packages such as bash-doc,
> >   >   emacs-common-non-dfsg (non-free repository for debian).
> >   > - ensure texinfo is installed in order to compile documentation
> >   >   when new emacs packages are installed.
> >
> > In principle this is desirable, but it may be complex.  For instance,
> > on various GNU/Linux distros the method is different.
> 
> Let's assume for the sake of argument that we only want to do this for
> Debian and derivatives.  That would require adding the non-free
> repository, thus indirectly encouraging users to use proprietary
> software.  Is that something we really would want to do?

That depend on what we say.  We don't have to mention Debian or their
repository explicitly -- which would also be better because other
distros could have a similar problem.

My problem with the suggestion is that I don't have a good idea where
to add the message.  We could:

  . display a special message when a manual is supposed to be part of
    Emacs; or
  . modify the message in case of a manual that wasn't found to better
    indicate that the user should try installing it

We could also do both.

But I don't think we should name the specific distros or their
specific package names; that way lies madness of having to maintain
those names forever.
  





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21  9:02     ` Eli Zaretskii
@ 2021-04-21 12:06       ` Stefan Kangas
  2021-04-21 12:16         ` Eli Zaretskii
  2021-04-21 12:32         ` Gregory Heytings
  0 siblings, 2 replies; 17+ messages in thread
From: Stefan Kangas @ 2021-04-21 12:06 UTC (permalink / raw)
  To: Eli Zaretskii; +Cc: marmot-te, 46236, rms

Eli Zaretskii <eliz@gnu.org> writes:

> That depend on what we say.  We don't have to mention Debian or their
> repository explicitly -- which would also be better because other
> distros could have a similar problem.

I have never seen or heard of any other distribution ripping out the
manual and distributing it separately from Emacs itself.  Do you know of
any examples?

> My problem with the suggestion is that I don't have a good idea where
> to add the message.  We could:
>
>   . display a special message when a manual is supposed to be part of
>     Emacs; or
>   . modify the message in case of a manual that wasn't found to better
>     indicate that the user should try installing it
>
> We could also do both.

When I say `C-h r' without `emacs-common-non-dfsg' installed on my
Debian machine, I get "Info file emacs does not exist".  I get the same
message when trying to follow the Info node reference from
`C-h f pcase', but it is complaining about the elisp manual.

Perhaps we could just find where that message comes from, add a list of
manuals that should always exist, and warn the user there if they don't.

> But I don't think we should name the specific distros or their
> specific package names; that way lies madness of having to maintain
> those names forever.

Given that Debian and its derivatives have a fairly dominant position,
and are the only ones suffering from this, I think this maintenance
overhead would be small.

Our job also got easier recently since Debian abandoned their "emacsNN"
packages (where NN is the major version) in favour of just versioned
"emacs".  So the packages used to be named "emacs24-common-non-dfsg",
but now they are just named "emacs-common-non-dfsg".

IOW, I think this would be easy to do technically, but it would need us
to recommend the "non-free" repository.

I'm therefore starting to think that this should be the responsibility
of Debian.  They should solve the problems that they have created for
their users; such a warning should be added by *them*.  Doesn't that
make more sense?





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 12:06       ` Stefan Kangas
@ 2021-04-21 12:16         ` Eli Zaretskii
  2021-04-21 12:40           ` Stefan Kangas
  2021-04-21 12:32         ` Gregory Heytings
  1 sibling, 1 reply; 17+ messages in thread
From: Eli Zaretskii @ 2021-04-21 12:16 UTC (permalink / raw)
  To: Stefan Kangas; +Cc: marmot-te, 46236, rms

> From: Stefan Kangas <stefan@marxist.se>
> Date: Wed, 21 Apr 2021 07:06:47 -0500
> Cc: rms@gnu.org, marmot-te@riseup.net, 46236@debbugs.gnu.org
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > That depend on what we say.  We don't have to mention Debian or their
> > repository explicitly -- which would also be better because other
> > distros could have a similar problem.
> 
> I have never seen or heard of any other distribution ripping out the
> manual and distributing it separately from Emacs itself.  Do you know of
> any examples?

It doesn't matter.  I'm saying that we shouldn't name them as a matter
of principle, so as to avoid the few pitfalls you've mentioned, like
talking about non-free repositories.

> When I say `C-h r' without `emacs-common-non-dfsg' installed on my
> Debian machine, I get "Info file emacs does not exist".

We could, for example, say something like

  Info manual for Emacs was not found; consider installing it.

which would be more explicit and clear, I think.

> Perhaps we could just find where that message comes from

It comes from Info-find-file.

> IOW, I think this would be easy to do technically, but it would need us
> to recommend the "non-free" repository.

Which is why I suggest not to name them.

> I'm therefore starting to think that this should be the responsibility
> of Debian.  They should solve the problems that they have created for
> their users; such a warning should be added by *them*.  Doesn't that
> make more sense?

We could indeed decide that it's not our problem.  In fact, the
current situation is tantamount to doing just that.





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 12:06       ` Stefan Kangas
  2021-04-21 12:16         ` Eli Zaretskii
@ 2021-04-21 12:32         ` Gregory Heytings
  2021-04-21 13:00           ` Eli Zaretskii
  2021-04-21 13:11           ` Stefan Kangas
  1 sibling, 2 replies; 17+ messages in thread
From: Gregory Heytings @ 2021-04-21 12:32 UTC (permalink / raw)
  To: Stefan Kangas; +Cc: marmot-te, 46236, rms


>
> When I say `C-h r' without `emacs-common-non-dfsg' installed on my 
> Debian machine, I get "Info file emacs does not exist".  I get the same 
> message when trying to follow the Info node reference from `C-h f 
> pcase', but it is complaining about the elisp manual.
>

A suggestion: when the info files bundled with Emacs cannot be found, 
download them from info.gnu.org (after asking the user if they're okay 
with that) and install them into ~/.emacs.d/info.  The info files that are 
supposed to be bundled with Emacs are not that big (about 5 MB, gzipped), 
and something similar (downloading data from a gnu.org site and install 
them into a ~/.emacs.d subdirectory) happens with M-x list-packages.





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 12:16         ` Eli Zaretskii
@ 2021-04-21 12:40           ` Stefan Kangas
  2021-04-21 15:32             ` Glenn Morris
  0 siblings, 1 reply; 17+ messages in thread
From: Stefan Kangas @ 2021-04-21 12:40 UTC (permalink / raw)
  To: Eli Zaretskii; +Cc: marmot-te, 46236, rms

Eli Zaretskii <eliz@gnu.org> writes:

> It doesn't matter.  I'm saying that we shouldn't name them as a matter
> of principle, so as to avoid the few pitfalls you've mentioned, like
> talking about non-free repositories.

Right, I see now what you are saying and I agree.

>> When I say `C-h r' without `emacs-common-non-dfsg' installed on my
>> Debian machine, I get "Info file emacs does not exist".
>
> We could, for example, say something like
>
>   Info manual for Emacs was not found; consider installing it.
>
> which would be more explicit and clear, I think.

That's very good, yes.  It points the user to the solution.

>> I'm therefore starting to think that this should be the responsibility
>> of Debian.  They should solve the problems that they have created for
>> their users; such a warning should be added by *them*.  Doesn't that
>> make more sense?
>
> We could indeed decide that it's not our problem.  In fact, the
> current situation is tantamount to doing just that.

I think the message you suggest above imposes almost no burden on us, so
that would be my first choice here.  That message is also useful even in
cases where there is no shenanigans from the distribution, but just an
info manual that wasn't installed.

If anyone asks us to do more than that, our reply could then be that it
is their problem to fix.





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 12:32         ` Gregory Heytings
@ 2021-04-21 13:00           ` Eli Zaretskii
  2021-04-21 13:47             ` Gregory Heytings
  2021-04-21 13:11           ` Stefan Kangas
  1 sibling, 1 reply; 17+ messages in thread
From: Eli Zaretskii @ 2021-04-21 13:00 UTC (permalink / raw)
  To: Gregory Heytings; +Cc: stefan, marmot-te, 46236, rms

> Date: Wed, 21 Apr 2021 12:32:38 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: Eli Zaretskii <eliz@gnu.org>, marmot-te@riseup.net, 46236@debbugs.gnu.org, 
>     rms@gnu.org
> 
> A suggestion: when the info files bundled with Emacs cannot be found, 
> download them from info.gnu.org (after asking the user if they're okay 
> with that) and install them into ~/.emacs.d/info.

We already have the latest manuals at

  https://www.gnu.org/software/emacs/manual/emacs.html

but what you suggest will require to maintain several versions back,
which is a non-trivial complication of the release procedures that are
already quite complex and tedious.  So I don't think we should take
this issue to be our problem to that level.





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 12:32         ` Gregory Heytings
  2021-04-21 13:00           ` Eli Zaretskii
@ 2021-04-21 13:11           ` Stefan Kangas
  2021-04-21 13:54             ` Gregory Heytings
  1 sibling, 1 reply; 17+ messages in thread
From: Stefan Kangas @ 2021-04-21 13:11 UTC (permalink / raw)
  To: Gregory Heytings; +Cc: marmot-te, 46236, rms

Gregory Heytings <gregory@heytings.org> writes:

> A suggestion: when the info files bundled with Emacs cannot be found,
> download them from info.gnu.org (after asking the user if they're okay
> with that) and install them into ~/.emacs.d/info.  The info files that are
> supposed to be bundled with Emacs are not that big (about 5 MB, gzipped),
> and something similar (downloading data from a gnu.org site and install
> them into a ~/.emacs.d subdirectory) happens with M-x list-packages.

I like the suggestion.  It would be a fun hack, if nothing else.

But I think the Debian maintainers might be upset, and it would be easy
for them to then disable this functionality.  So in some ways, I'd
rather that users of Debian complain so that they fix the root cause:
that they don't ship GFDL manuals.  OTOH, that is exceedingly unlikely
to happen any time soon.

Perhaps the Debian maintainers won't care, and this is a fine solution
to the problem that they created.  It really is unfortunate that Emacs
is so crippled on the most popular GNU/Linux distributions, so we might
have reason to take a more aggressive stance.

So yeah, I don't know...





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 13:00           ` Eli Zaretskii
@ 2021-04-21 13:47             ` Gregory Heytings
  0 siblings, 0 replies; 17+ messages in thread
From: Gregory Heytings @ 2021-04-21 13:47 UTC (permalink / raw)
  To: Eli Zaretskii; +Cc: stefan, marmot-te, 46236, rms


>> A suggestion: when the info files bundled with Emacs cannot be found, 
>> download them from info.gnu.org (after asking the user if they're okay 
>> with that) and install them into ~/.emacs.d/info.
>
> We already have the latest manuals at
>
>  https://www.gnu.org/software/emacs/manual/emacs.html
>
> but what you suggest will require to maintain several versions back, 
> which is a non-trivial complication of the release procedures that are 
> already quite complex and tedious.  So I don't think we should take this 
> issue to be our problem to that level.
>

In fact this makes it even easier than what I thought: it would suffice to 
add 60 files in the https://www.gnu.org/software/emacs/manual/info/ 
directory.  Of course there's the version problem.  Perhaps an 
"emacs-version" file could be added in that directory, it would be 
compared against emacs-version, with a warning when the files are for a 
more recent version.





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 13:11           ` Stefan Kangas
@ 2021-04-21 13:54             ` Gregory Heytings
  2021-04-21 14:13               ` Stefan Kangas
  0 siblings, 1 reply; 17+ messages in thread
From: Gregory Heytings @ 2021-04-21 13:54 UTC (permalink / raw)
  To: Stefan Kangas; +Cc: marmot-te, 46236, rms


>
> But I think the Debian maintainers might be upset, and it would be easy 
> for them to then disable this functionality.
>

Why would they be?  They already distribute these files in a separate 
package, so AFAICS they have no reason to prevent their users from doing 
the same.

>
> So in some ways, I'd rather that users of Debian complain so that they 
> fix the root cause: that they don't ship GFDL manuals.  OTOH, that is 
> exceedingly unlikely to happen any time soon.
>

I fear it is, indeed.





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 13:54             ` Gregory Heytings
@ 2021-04-21 14:13               ` Stefan Kangas
  0 siblings, 0 replies; 17+ messages in thread
From: Stefan Kangas @ 2021-04-21 14:13 UTC (permalink / raw)
  To: Gregory Heytings; +Cc: marmot-te, 46236, rms

Gregory Heytings <gregory@heytings.org> writes:

>> But I think the Debian maintainers might be upset, and it would be easy
>> for them to then disable this functionality.
>
> Why would they be?  They already distribute these files in a separate
> package, so AFAICS they have no reason to prevent their users from doing
> the same.

I mean, I don't know, obviously.

But we would in a sense short-circuit their [IMO incorrect, pedantic and
damaging] decision to mark GFDL manuals "non-free".





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 12:40           ` Stefan Kangas
@ 2021-04-21 15:32             ` Glenn Morris
  2021-04-21 16:34               ` Stefan Kangas
  0 siblings, 1 reply; 17+ messages in thread
From: Glenn Morris @ 2021-04-21 15:32 UTC (permalink / raw)
  To: Stefan Kangas; +Cc: marmot-te, 46236


IMO it's obviously Debian's responsibility to fix this.
If they want to remove an info file, they should replace it with a stub that
says that they did so, and explains how to get the original.
It would seem simple to do so.
But given that this has not happened in 15 years, it seems unlikely to.

See eg https://bugs.debian.org/961593
(But I'm sure this must have been discussed before that.)

(This problem is of course not specific to Emacs info files.)





^ permalink raw reply	[flat|nested] 17+ messages in thread

* bug#46236: 26.1; explicit the info files installation
  2021-04-21 15:32             ` Glenn Morris
@ 2021-04-21 16:34               ` Stefan Kangas
  0 siblings, 0 replies; 17+ messages in thread
From: Stefan Kangas @ 2021-04-21 16:34 UTC (permalink / raw)
  To: Glenn Morris; +Cc: marmot-te, 46236

tags 46236 fixed
close 46236 28.1
thanks

Glenn Morris <rgm@gnu.org> writes:

> IMO it's obviously Debian's responsibility to fix this.
> If they want to remove an info file, they should replace it with a stub that
> says that they did so, and explains how to get the original.
> It would seem simple to do so.
> But given that this has not happened in 15 years, it seems unlikely to.
>
> See eg https://bugs.debian.org/961593
> (But I'm sure this must have been discussed before that.)
>
> (This problem is of course not specific to Emacs info files.)

That's true.

So I installed the improved error message suggested by Eli, and I'm
closing this bug.





^ permalink raw reply	[flat|nested] 17+ messages in thread

end of thread, other threads:[~2021-04-21 16:34 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-02-01 14:10 bug#46236: 26.1; explicit the info files installation marmot-te
2021-02-03  5:48 ` Richard Stallman
2021-04-21  3:20   ` Stefan Kangas
2021-04-21  9:02     ` Eli Zaretskii
2021-04-21 12:06       ` Stefan Kangas
2021-04-21 12:16         ` Eli Zaretskii
2021-04-21 12:40           ` Stefan Kangas
2021-04-21 15:32             ` Glenn Morris
2021-04-21 16:34               ` Stefan Kangas
2021-04-21 12:32         ` Gregory Heytings
2021-04-21 13:00           ` Eli Zaretskii
2021-04-21 13:47             ` Gregory Heytings
2021-04-21 13:11           ` Stefan Kangas
2021-04-21 13:54             ` Gregory Heytings
2021-04-21 14:13               ` Stefan Kangas
2021-03-06 14:25 ` Tomas Nordin
2021-03-07  6:11   ` Richard Stallman

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/emacs.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).