I am experiencing font issues for a few specific characters, namely the "SYMBOL FOR …" family, which are textual representations of control characters such as NUL, BEL, BS, etc.
This screenshot shows:
on the left,
emacs -Q
, with completion candidates forC-x 8 RET SYMBOL FOR
;on the right, a Terminator console running Python, displaying some of the same characters.
Not shown: a file containing some of these characters, opened with the Geany text editor. Geany displays the same glyphs as Terminator.
While the symbols on the left are rather cute, I would rather have Emacs show the same glyphs as Terminator and Geany. I have no idea of what causes this though. Terminator and Geany both use the Monospace font, but customizing Emacs's default
face to Monospace does not change the situation. I do not know yet whether the issue comes from:
- my system (font cache, what have you);
- my Emacs configuration (unlikely, since
-Q
includes--no-init-file --no-site-file
); - the Emacs software.
C-u C-x =
on e.g. SYMBOL FOR NULL has this to say about the character:
position: 146 of 151 (96%), column: 0
character: ␀ (displayed as ␀) (codepoint 9216, #o22000, #x2400)
preferred charset: unicode (Unicode (ISO10646))
code point in charset: 0x2400
script: symbol
syntax: _ which means: symbol
category: .:Base, c:Chinese
to input: type "C-x 8 RET 2400" or "C-x 8 RET SYMBOL FOR NULL"
buffer code: #xE2 #x90 #x80
file code: #xE2 #x90 #x80 (encoded by coding system utf-8-unix)
display: by this font (glyph code)
xft:-unknown-Symbola-normal-normal-semicondensed-*-15-*-*-*-*-0-iso10646-1 (#x77D)
Character code properties: customize what to show
name: SYMBOL FOR NULL
old-name: GRAPHIC FOR NULL
general-category: So (Symbol, Other)
decomposition: (9216) ('␀')
There are text properties here:
fontified t
Note that emacs -nw
is unaffected, i.e. the characters on the right side of the screenshot are shown. I guess Terminator takes care of font selection in this case? 🤷
I would appreciate any input on the subject. I do not know whether this warrants a bug report, since for all I know my whole setup is working "as intended" for some value of "intended".
Emacs version: GNU Emacs 25.1.1 (i686-pc-linux-gnu, GTK+ Version 3.14.5)
Terminator version: terminator 0.97
Python version: Python 3.4.2
Geany version: geany 1.24.1 (built on 2014-04-19 with GTK 2.24.23, GLib 2.40.0)
OS: BunsenLabs GNU/Linux 8.5 (Hydrogen) (essentially Debian Jessie)
PS: I tried to reproduce on a Xubuntu 14.04 machine, and saw intricate glyphs composed of a square box, featuring the acronym (e.g. NUL, BS) in the bottom half and the weird symbol (e.g. heart, spades) in the top-right corner (could not take a screenshot unfortunately).
PS2: now that I've copy-pasted the above code-block in Firefox (49.0), I can also add that Firefox uses the same glyph than Terminator and Geany.