[XeTeX] turn off special characters in PDF

[Khaled Hosny]

On Sun, Dec 29, 2013 at 09:12:28PM +0000, Joe Corneli wrote:
> This answer talks about how to turn off litgatures:
> http://tex.stackexchange.com/a/5419/4357
> 
> Is there a way to turn off *all* special characters (e.g. small caps)
> and just get ASCII characters in the copy-and-paste level of the PDF?

It should just works (unless it is a MS font with no glyph names or font
that uses PUA for those alternate glyphs, in this case the only solution
is to wait for the next TeX Live where this will, hopefully, be
handled).

Regards,
Khaled