Dependent on a text file in /usr/X11R6/

[James Wright]

If I have a port that needs a text file that is installed with the X 
sets, but needs nothing else of X, what is the correct way to indicate 
that?  Should I assume X is installed, make it as USE_X11 or have a copy 
of the file in files/ and copy it to /usr/local/share/packagename?