bug#66993: [PATCH] project.el: avoid asking user about project-list-file lock

[Dmitry Gutov <dmitry@gutov.dev>]

On 09/11/2023 08:37, Eli Zaretskii wrote:
>> Date: Wed, 8 Nov 2023 23:04:50 +0200
>> Cc:66993@debbugs.gnu.org
>> From: Dmitry Gutov<dmitry@gutov.dev>
>>
>> On 08/11/2023 18:32, Eli Zaretskii wrote:
>>> I thought these writes were already just adding projects, not
>>> clobbering the list.
>> The file is re-written in full every time e.g. to remove the previous
>> mentions of a project that should now be moved to the top.
> I don't understand how this resolves the concern about clobbering.  If
> each Emacs session just writes its list of projects to the file,
> without refreshing the list due to additions done by another session,
> they will still clobber each other's lists, no?  This could be avoided
> if the writer would read the file before rewriting it.

Not resolves. Explains.

> Can you tell why the list of projects is saved on a file that is
> global among all sessions of the same user?  Would it make sense to
> make the file specific to an Emacs process?

Specific, meaning in a file name e.g. suffixed with pid?

And what happens after the restart? The list needs to be recovered.