Re: Can watermarking Unicode text using invisible differences sneak through Emacs, or can Emacs detect it?

[Eli Zaretskii]

> From: Tomas Hlavaty <tom@logand.com>
> Cc: eliz@gnu.org, psainty@orcon.net.nz, luangruo@yahoo.com,
>       emacs-devel@gnu.org, kevin.legouguec@gmail.com
> Date: Sat, 05 Feb 2022 14:55:19 +0100
> 
> 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?

Also, these calls are incorrect:

 (char-displayable-p ?ã¯)
 (char-displayable-p ?ã˘)

char-displayable-p accepts a single character, not 2.