[NTG-context] Forcing XeTeX output

[Philipp Reichmuth]

Hi,

is there a first-line comment directive or a \setupoutput[] parameter to 
force usage of XeTeX just like the --xtx commandline switch?

Consider the following document:

----------------------
% ??? = xetex???
\starttext
This is a piece of text
\stoptext
----------------------

I just experimentally tried "engine=xetex", "tex=xetex" and 
"output=xetex" on the first line.  The first two actually launch XeTeX, 
but they bail out with the comment "you should use pdfetex instad" and a 
\wait command, and the last one runs pdfetex instead and produces a DVI 
file.

Philipp