trivia, but it's a niggle

Have you looked carefully at RFC 1738 lately (URLs)?

1) There is no production there for URLchar.  If I had to guess, I'd
guess we want the production for xchar (not helpfully named, is it?).

2) There's not much there about relative references, is there :-(

3) Unless I can't decode their semi-bnf correctly, the syntax we all
use for file URLs is actually bogus, namely

file:/home/ht/mymasterpiece.xml

As I read the relevant productions, we should be saying

file:///home/ht/mymasterpiece.xml

Do we care?  Does anyone?

4) Is

/home/ht/mymasterpiece.xml

a valid relative URL if the base is a file?

I.e. is <!doctype foo SYSTEM '/home/ht/xml/foo.dtd'> valid XML?

ht