In XSLT, we can specify the output options by using the <xsl:output method="xml"  doctype-system=".." ..../>, how do we specify the output options in XQuery? 
What I want to do is there is one XQuery file, which contains all the functions and other things( possibly the output options), then during the run time, I can just apply this XQuery file to the source XML and get the result XML.  But I don't know how to specify the output options within the XQuery file, I know I can use the output properites, but these properties seem have to store outside the XQuery file and during the run time, I have to manually set them and then pass them to the serialize function.
Thanks for your help.