bug#53814: process-status returns invalid/undocumented status file-error for network process

[emacsq]

>
> Apparently, process.c does set this this invalid status for some
> reason:
>
>   Lisp_Object data = get_file_errno_data (err, contact, xerrno);
>   pset_status (p, list2 (Fcar (data), Fcdr (data)));
>   unbind_to (count, Qnil);
>   return;
>

So process.c sets the status to file-error, and it also has
error message obtained via get_file_errno_data.

I checked what it says for such a process:

("make client process failed" "Too many open files" :name "example.com" ...)

So I guess it's a too many open connections error, but instead of
saying that, it sets the status to the undocumented file-error.

What's strange is when I delete such a 'file-error' process from
the process list, then it immediately goes to connect and then open
state for the given domain, which is not clear for me how it is
possible, since delete-process removes the process from the list
of processes.