[xsl] Xmllint and xsltproc standard in support

[list@xxxxxxxxxxx]

This is really more of a wish than a support question.

Can the tools use stdin as an input stream? the tools themselves would 
use some sort of stream based sax parser. This would make them very much 
more useful.

I was hoping to

myprog | xmlint --format -

and

myprog | xmlint - | xsltproc validator.xslt -

Just to get an indication, is this a simple patch or a major rework to 
provide that function?