Re: tramp "too many open files" [Re: bug#56606

[Madhu <enometh@meer.net>]

*  Michael Albinus <87ttyfzcpf.fsf @gmx.de>
Wrote on Mon, 20 Mar 2023 16:04:12 +0100
> Madhu <enometh@meer.net> writes:
>> The #56606 is archived and this may be unrelated and related to tramp,
>> but I wanted to note I encoutered something similar on recent master
>> (GNU Emacs 30.0.50 (build 2, x86_64-pc-linux-gnu, X toolkit, cairo
>> version 1.16.0, Xaw3d scroll bars) of 2023-03-18) native compilation.
>
> I might be wrong, but likely, bug#56606 is unrelated.

Thanks for your note, Sorry for the false alarm.

>
> Hmm. tramp-archive.el uses th GVFS file system to read a file
> archive. GVFS in this case uses libarchive(3).

I notice my gvfsd is not compiled with libarchive.

>> Of course I could do nothing but kill the process. I updated mew to 6.9
>> and tried the sequence again in a fresh emacs, but wasn't able to
>> reproduce this (but hit a vertico bug instead)
>>
>> If this looks familiar, or if someone has a clue about it, please tell
>> me. Maybe I should a bug report under the `tramp' product if I hit it
>> again.
>
> What I could imagine is, that Emacs has many of the files open from the zip
> file. However, mew shouldn't use tramp-archive.el ...

Ah, I might have made a mistake when entering the filename: by adding
"foo.zip/" when saving the file (it uses read-file-name)

> Well, I'm not familiar with mew. Could you please write a bug report,
> which contains a recipe starting with "emacs -Q", and which tells how to
> reach the point when the error appeared as reported above. The recipe is
> also good when it doesn't show the error; I want to use it in order to
> see how tramp-archive.el comes into play.

Usually I run without a system dbus (but with a session dbus for
emacs). tramp-archive disables itself when it finds it cannot connect
to a system dbus, so I was protected from it being triggered. (btw if
the situation changes, and a system dbus comes up later, it has to be
initialized explicitly with (dbus-init-bus :system))

I think I happened to have a system dbus when I triggered the
error. tramp found a gvfs and gvfs-fuse process, but it wouldn't have
worked because gvfds is not linked with libarchive.

So far I've not able to reproduce the error and am not sure. When I
try to trigger it with a filename with like /tmp/foo.zip/sle.txt, it
just says that there is no such directory.

[I'll try to compile gvfsd with libarchive and try again later, but it
will take some time to unscrew and fix the gentoo config: I have to
update libarchive, and that requires undoing some upstream e2fsprogs
decisions.]