From: <tomas@tuxteam.de>
To: emacs-devel@gnu.org
Subject: Re: file-equal-p
Date: Fri, 17 Feb 2023 13:45:57 +0100 [thread overview]
Message-ID: <Y+93BZHhVkY2Y1GP@tuxteam.de> (raw)
In-Reply-To: <83ilg01nst.fsf@gnu.org>
[-- Attachment #1: Type: text/plain, Size: 1359 bytes --]
On Fri, Feb 17, 2023 at 02:25:38PM +0200, Eli Zaretskii wrote:
> > From: Andreas Schwab <schwab@linux-m68k.org>
> > Cc: Po Lu <luangruo@yahoo.com>, emacs-devel@gnu.org
> > Date: Fri, 17 Feb 2023 11:02:48 +0100
> >
> > On Feb 16 2023, Richard Stallman wrote:
> >
> > > If so, can Emacs examine it using that other way?
> >
> > The right way to solve the issue is to only compare the inode and device
> > numbers. The other attributes (other than the type) can change any time
> > for unrelated reasons, and do not define the identity of a file.
>
> That depends on the semantics of "files are equal". If the issue is
> only whether two file names point to the same file's data, then yes,
> using file-attribute-file-identifier is TRT.
This is how I read `file-equal-p''s docstring [1] (coming from Lisp,
I'd called it `file-eq-p', but hey :-)
> But that is not the only
> possible semantics of these tests. It is therefore up to the
> application to decide which API to use, IMO.
>
> Of course, as long as the file is identified only by its name, race
> condition is possible even if we only compare the inode and the device
> number.
Identity is always difficult in a mutable world, yes.
Cheers
[1] Return non-nil if files FILE1 and FILE2 name the same file.
--
t
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 195 bytes --]
next prev parent reply other threads:[~2023-02-17 12:45 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <87a61es8fh.fsf.ref@yahoo.com>
2023-02-16 1:30 ` file-equal-p Po Lu
2023-02-16 8:18 ` file-equal-p Eli Zaretskii
2023-02-16 8:43 ` file-equal-p Po Lu
2023-02-16 8:57 ` file-equal-p Eli Zaretskii
2023-02-16 9:59 ` file-equal-p Po Lu
2023-02-16 11:52 ` file-equal-p Eli Zaretskii
2023-02-16 12:34 ` file-equal-p Po Lu
2023-02-16 12:42 ` file-equal-p Eli Zaretskii
2023-02-17 2:40 ` file-equal-p Po Lu
2023-02-17 6:26 ` file-equal-p Eli Zaretskii
2023-02-17 7:07 ` file-equal-p Po Lu
2023-02-17 8:32 ` file-equal-p Eli Zaretskii
2023-02-17 11:05 ` file-equal-p Po Lu
2023-02-16 9:15 ` file-equal-p Andreas Schwab
2023-02-16 9:58 ` file-equal-p Po Lu
2023-02-16 10:35 ` file-equal-p Michael Albinus
2023-02-16 12:35 ` file-equal-p Po Lu
2023-02-16 12:43 ` file-equal-p Eli Zaretskii
2023-02-17 4:50 ` file-equal-p Richard Stallman
2023-02-17 10:02 ` file-equal-p Andreas Schwab
2023-02-17 12:25 ` file-equal-p Eli Zaretskii
2023-02-17 12:45 ` tomas [this message]
2023-02-17 13:17 ` file-equal-p Andreas Schwab
2023-02-18 12:25 ` file-equal-p Eli Zaretskii
2023-02-18 14:04 ` file-equal-p Andreas Schwab
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: https://www.gnu.org/software/emacs/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y+93BZHhVkY2Y1GP@tuxteam.de \
--to=tomas@tuxteam.de \
--cc=emacs-devel@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).