[Fontconfig] How to block glyph fallback in a QT application?

[Janusz S. Bien]

Quote/Cytat - Behdad Esfahbod <behdad at behdad.org> (Mon 06 Jan 2014  
03:57:06 PM CET):

> On 14-01-06 10:46 PM, Janusz S. Bien wrote:
>> Quote/Cytat - Raimund Steger <rs at mytum.de> (Mon 06 Jan 2014  
>> 02:51:29 PM CET):
>>
>>> Hi,
>>>
>>> On Mon, January 6, 2014 07:13, Janusz S. Bien wrote:
>>>> [...]
>>>> incidentally selects an improper font, then fallback creates quite a
>>>> mess.
>>>
>>> What kind of mess are you seeing --
>>>
>>> * empty squares showing (= no glyph fallback)
>>
>> That's what I would like to have when the user selects a wrong font.
>
> You need to ask Qt then.  Little that can be done in fontconfig.

The problem doesn't seem to be QT specific. On several versions of  
Debian I never get empty squares in any application - for example  
gnucharmap is quite confusing for this reason.

Best regards

Janusz

-- 
Prof. dr hab. Janusz S. Bień -  Uniwersytet Warszawski (Katedra  
Lingwistyki Formalnej)
Prof. Janusz S. Bień - University of Warsaw (Formal Linguistics Department)
jsbien at uw.edu.pl, jsbien at mimuw.edu.pl, http://fleksem.klf.uw.edu.pl/~jsbien/