From: Eli Zaretskii <eliz@gnu.org>
To: tom@logand.com
Cc: psainty@orcon.net.nz, luangruo@yahoo.com, emacs-devel@gnu.org,
rms@gnu.org, kevin.legouguec@gmail.com
Subject: Re: Can watermarking Unicode text using invisible differences sneak through Emacs, or can Emacs detect it?
Date: Sat, 05 Feb 2022 16:12:58 +0200 [thread overview]
Message-ID: <83h79d1jx1.fsf@gnu.org> (raw)
In-Reply-To: <83iltt1k7h.fsf@gnu.org> (message from Eli Zaretskii on Sat, 05 Feb 2022 16:06:42 +0200)
> Date: Sat, 05 Feb 2022 16:06:42 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: psainty@orcon.net.nz, luangruo@yahoo.com, kevin.legouguec@gmail.com,
> rms@gnu.org, emacs-devel@gnu.org
>
> > char-displayable-p returns non-nil even though I see boxes.
>
> Is this the Linux console or is this a terminal emulator?
>
> If it's a console, does it support the ioctl issued by
> calculate_glyph_code_table?
I guess the answer is NO, because if it did, you'd see t as the return
value, not 'unicode'.
So then it isn't surprising that you get false positives when your
terminal-coding-system is UTF-8: that coding-system can encode any
character, and Emacs has no way of knowing which of them actually have
glyphs in the console font if the console doesn't support the
GIO_UNIMAP ioctl we use to find out which glyphs are actually
available.
next prev parent reply other threads:[~2022-02-05 14:12 UTC|newest]
Thread overview: 104+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-19 4:15 Can watermarking Unicode text using invisible differences sneak through Emacs, or can Emacs detect it? Richard Stallman
2022-01-19 4:47 ` Po Lu
2022-01-19 10:05 ` Phil Sainty
2022-01-19 11:43 ` Eli Zaretskii
2022-01-21 4:13 ` Richard Stallman
2022-01-21 7:49 ` Eli Zaretskii
2022-01-22 4:37 ` Richard Stallman
2022-01-22 6:58 ` Eli Zaretskii
2022-01-24 4:33 ` Richard Stallman
2022-01-24 5:06 ` Po Lu
2022-01-25 4:17 ` Richard Stallman
2022-01-25 4:58 ` Po Lu
2022-01-24 12:14 ` Eli Zaretskii
2022-01-25 4:16 ` Richard Stallman
2022-01-25 6:35 ` Eli Zaretskii
2022-01-25 12:12 ` Eli Zaretskii
2022-01-25 4:16 ` New feature: displaying ligature characters in the buffer Richard Stallman
2022-01-25 6:31 ` Eli Zaretskii
2022-01-27 4:12 ` Richard Stallman
2022-01-27 7:58 ` Eli Zaretskii
2022-01-25 11:08 ` Can watermarking Unicode text using invisible differences sneak through Emacs, or can Emacs detect it? Kévin Le Gouguec
2022-01-25 12:38 ` Eli Zaretskii
2022-01-26 3:39 ` Richard Stallman
2022-01-26 5:38 ` Eli Zaretskii
2022-01-28 13:04 ` Richard Stallman
2022-01-28 13:31 ` Eli Zaretskii
2022-01-30 4:17 ` Richard Stallman
2022-01-30 7:36 ` Eli Zaretskii
2022-01-31 4:02 ` Richard Stallman
2022-01-31 13:05 ` Eli Zaretskii
2022-02-01 5:06 ` Richard Stallman
2022-02-01 14:57 ` Eli Zaretskii
2022-02-02 3:58 ` Richard Stallman
2022-02-02 12:28 ` Eli Zaretskii
2022-02-03 4:23 ` Richard Stallman
2022-02-03 7:53 ` Eli Zaretskii
2022-02-03 8:16 ` Yuri Khan
2022-02-03 9:26 ` Eli Zaretskii
2022-02-04 3:52 ` Richard Stallman
2022-02-04 4:56 ` Yuri Khan
2022-02-06 4:13 ` Richard Stallman
2022-02-04 8:10 ` Eli Zaretskii
2022-02-06 4:13 ` Richard Stallman
2022-02-03 20:28 ` Tomas Hlavaty
2022-02-04 7:07 ` Eli Zaretskii
2022-02-05 4:20 ` Richard Stallman
2022-02-05 13:55 ` Tomas Hlavaty
2022-02-05 14:06 ` Eli Zaretskii
2022-02-05 14:12 ` Eli Zaretskii [this message]
2022-02-06 1:29 ` Tomas Hlavaty
2022-02-06 8:30 ` Eli Zaretskii
2022-02-06 10:38 ` Tomas Hlavaty
2022-02-06 10:44 ` Eli Zaretskii
2022-02-06 10:54 ` Andreas Schwab
2022-02-06 1:10 ` Tomas Hlavaty
2022-02-06 4:16 ` Richard Stallman
2022-02-06 4:16 ` Richard Stallman
2022-02-06 11:29 ` Tomas Hlavaty
2022-02-04 3:52 ` Richard Stallman
2022-02-04 8:03 ` Eli Zaretskii
2022-02-06 4:13 ` Richard Stallman
2022-02-06 8:56 ` Eli Zaretskii
2022-02-07 5:11 ` Richard Stallman
2022-02-07 13:16 ` Eli Zaretskii
2022-02-08 3:55 ` Richard Stallman
2022-02-08 12:20 ` Eli Zaretskii
2022-02-09 4:06 ` Richard Stallman
2022-02-09 13:50 ` Eli Zaretskii
2022-02-10 3:57 ` Richard Stallman
2022-02-10 6:26 ` Eli Zaretskii
2022-02-12 3:57 ` Richard Stallman
2022-02-12 7:36 ` Eli Zaretskii
2022-02-14 4:13 ` Richard Stallman
2022-02-14 12:07 ` Eli Zaretskii
2022-02-15 4:33 ` Richard Stallman
2022-02-15 13:32 ` Eli Zaretskii
2022-02-16 4:14 ` Richard Stallman
2022-02-16 12:10 ` Eli Zaretskii
2022-02-19 4:54 ` Richard Stallman
2022-02-12 20:10 ` Tomas Hlavaty
2022-02-14 4:14 ` Richard Stallman
2022-01-26 8:20 ` Andreas Schwab
2022-01-27 4:13 ` Richard Stallman
2022-01-27 6:39 ` Eli Zaretskii
2022-01-27 8:13 ` Kévin Le Gouguec
2022-01-27 9:55 ` Eli Zaretskii
2022-01-27 10:29 ` Eli Zaretskii
2022-01-27 17:36 ` Kévin Le Gouguec
2022-01-27 18:38 ` Eli Zaretskii
2022-01-20 3:17 ` Richard Stallman
2022-01-20 4:54 ` Phil Sainty
2022-01-20 6:39 ` tomas
2022-01-20 17:58 ` [External] : " Drew Adams
2022-01-22 4:37 ` Richard Stallman
2022-01-22 5:16 ` Po Lu
2022-01-20 7:57 ` Eli Zaretskii
2022-01-20 6:35 ` Tim Cross
2022-01-20 7:39 ` tomas
2022-01-20 8:20 ` Eli Zaretskii
2022-01-20 7:48 ` Eli Zaretskii
2022-01-20 8:17 ` Lars Ingebrigtsen
2022-01-21 4:14 ` Richard Stallman
2022-01-19 8:20 ` Eli Zaretskii
2022-01-19 17:36 ` T.V Raman
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