How to print unicode characters (no library)?

[rempas]

On Monday, 27 December 2021 at 09:29:38 UTC, Kagamin wrote:
> D strings are plain arrays without any text-specific logic, the 
> element is called code unit, which has a fixed size, and the 
> array length specifies how many elements are in the array. This 
> model is most adequate for memory correctness, i.e. it shows 
> what takes how much memory and where it will fit. D doesn't 
> impose fixed interpretations like characters or code points, 
> because there are many of them and neither is the correct one, 
> you need one or another in different situations. Linux console 
> one example of such situation: it doesn't accept characters or 
> code points, it accepts utf8 code units, using anything else is 
> an error.

So should I just use UTF-8 only for Linux? What about other 
operating systems? I suppose Unix-based OSs (maybe MacOS as well 
if I'm lucky) work the same as well. But what about Windows? 
Unfortunately I have to support this OS too with my library so I 
should know. If you know and you can tell me of course...