bug#69987: 28.2; *mailcap shell* not in buffer list

bug#69987: 28.2; *mailcap shell* not in buffer list

[tom]

After switching away from *mailcap shell* buffer
there is no way to get back to it.
At least I cannot find it in the *Buffer List* buffer.
Would it be possible to keep the *mailcap shell* buffer
around as usual?  This automagical disappearance is
rather inconvenient and surprising.



In GNU Emacs 28.2 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo version 1.16.0, Xaw3d scroll bars)
System Description: NixOS 23.05 (Stoat)

Configured using:
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bug#69987: 28.2; *mailcap shell* not in buffer list

[Eli Zaretskii]

> From: tom@logand.com
> Date: Sun, 24 Mar 2024 20:12:54 +0100
> 
> After switching away from *mailcap shell* buffer
> there is no way to get back to it.
> At least I cannot find it in the *Buffer List* buffer.
> Would it be possible to keep the *mailcap shell* buffer
> around as usual?  This automagical disappearance is
> rather inconvenient and surprising.

Can you show a recipe, preferably starting from "emacs -Q"?  Or at
least explain how you get to this *mailcap shell* buffer?  That would
help us investigate the issue.

A stab in the dark: if the buffer's name is actually " *mailcap shell*",
i.e. it begins with a space, then you can switch to it by typing its
name at the "C-x b" prompt.

bug#69987: 28.2; *mailcap shell* not in buffer list

[Tomas Hlavaty]

Hi Eli,

thanks for the quick reply.

> Can you show a recipe, preferably starting from "emacs -Q"?  Or at
> least explain how you get to this *mailcap shell* buffer?

$ emacs -Q --eval='(eww
"https://dq4n3btxmr8c9.cloudfront.net/files/oj7hht/Liberties_Rule_Of_Law_Report_2024_FULL.pdf")'

then C-x 1 to hide the *mailcal shell* buffer

then C-x C-b to show *Buffer List*

> A stab in the dark: if the buffer's name is actually " *mailcap shell*",
> i.e. it begins with a space,

you are right, fascinating

> then you can switch to it by typing its name at the "C-x b" prompt.

this works, thank you!

although not very discoverable

Where could I learn more about such buffer name conventions?

Regards,

Tomas

bug#69987: 28.2; *mailcap shell* not in buffer list

[Stephen Berman via Bug reports for GNU Emacs, the Swiss army knife of text editors]

On Sun, 24 Mar 2024 23:25:50 +0100 Tomas Hlavaty <tom@logand.com> wrote:

> Hi Eli,
>
> thanks for the quick reply.
>
>> Can you show a recipe, preferably starting from "emacs -Q"?  Or at
>> least explain how you get to this *mailcap shell* buffer?
>
> $ emacs -Q --eval='(eww
> "https://dq4n3btxmr8c9.cloudfront.net/files/oj7hht/Liberties_Rule_Of_Law_Report_2024_FULL.pdf")'
>
> then C-x 1 to hide the *mailcal shell* buffer
>
> then C-x C-b to show *Buffer List*
>
>> A stab in the dark: if the buffer's name is actually " *mailcap shell*",
>> i.e. it begins with a space,
>
> you are right, fascinating
>
>> then you can switch to it by typing its name at the "C-x b" prompt.
>
> this works, thank you!
>
> although not very discoverable
>
> Where could I learn more about such buffer name conventions?

In the Emacs user's manual (info "(emacs) List Buffers"):

   21.2 Listing Existing Buffers
   =============================
   
   ‘C-x C-b’
        List the existing buffers (‘list-buffers’).
   [...]
      ‘list-buffers’ omits buffers whose names begin with a space, unless
   they visit files: such buffers are used internally by Emacs.

With `M-x ibuffer' you get a table of all buffers, including those
beginning with a space, by typing `C-u g' in the *Ibuffer* buffer.

Steve Berman

bug#69987: 28.2; *mailcap shell* not in buffer list

[Tomas Hlavaty]

On Mon 25 Mar 2024 at 00:25, Stephen Berman <stephen.berman@gmx.net> wrote:
> (info "(emacs) List Buffers")

thank you!

bug#69987: 28.2; *mailcap shell* not in buffer list

[Juri Linkov]

> then C-x C-b to show *Buffer List*

In the *Buffer List* you can see all internal buffers
by typing 'I' (Buffer-menu-toggle-internal).

bug#69987: 28.2; *mailcap shell* not in buffer list

[Stephen Berman via Bug reports for GNU Emacs, the Swiss army knife of text editors]

On Mon, 25 Mar 2024 09:55:37 +0200 Juri Linkov <juri@linkov.net> wrote:

>> then C-x C-b to show *Buffer List*
>
> In the *Buffer List* you can see all internal buffers
> by typing 'I' (Buffer-menu-toggle-internal).

Does the "---" line above the NEWS entry for this feature mean the "List
Buffers" node in the Emacs manual will be updated to mention it?

Steve Berman

bug#69987: 28.2; *mailcap shell* not in buffer list

[Eli Zaretskii]

> From: Stephen Berman <stephen.berman@gmx.net>
> Cc: Tomas Hlavaty <tom@logand.com>,  69987@debbugs.gnu.org,  Eli Zaretskii
>  <eliz@gnu.org>
> Date: Mon, 25 Mar 2024 09:33:23 +0100
> 
> On Mon, 25 Mar 2024 09:55:37 +0200 Juri Linkov <juri@linkov.net> wrote:
> 
> >> then C-x C-b to show *Buffer List*
> >
> > In the *Buffer List* you can see all internal buffers
> > by typing 'I' (Buffer-menu-toggle-internal).
> 
> Does the "---" line above the NEWS entry for this feature mean the "List
> Buffers" node in the Emacs manual will be updated to mention it?

No, it means we didn't think this worth documenting.  Now reconsidered.

I'm therefore closing this bug.

bug#69987: 28.2; *mailcap shell* not in buffer list

[Stephen Berman via Bug reports for GNU Emacs, the Swiss army knife of text editors]

On Mon, 25 Mar 2024 14:55:12 +0200 Eli Zaretskii <eliz@gnu.org> wrote:

>> From: Stephen Berman <stephen.berman@gmx.net>
>> Cc: Tomas Hlavaty <tom@logand.com>,  69987@debbugs.gnu.org,  Eli Zaretskii
>>  <eliz@gnu.org>
>> Date: Mon, 25 Mar 2024 09:33:23 +0100
>>
>> On Mon, 25 Mar 2024 09:55:37 +0200 Juri Linkov <juri@linkov.net> wrote:
>>
>> >> then C-x C-b to show *Buffer List*
>> >
>> > In the *Buffer List* you can see all internal buffers
>> > by typing 'I' (Buffer-menu-toggle-internal).
>>
>> Does the "---" line above the NEWS entry for this feature mean the "List
>> Buffers" node in the Emacs manual will be updated to mention it?
>
> No, it means we didn't think this worth documenting.  Now reconsidered.

Thanks.

Steve Berman