File: URI scheme gotcha

Question

This is mainly a public note to myself; maybe it will help others, and maybe it will be even added to the FAQ and used to amend the relevant sections of the documentation. Trying to load a document from the filesystem, I've just again run into this issue of the file: URI weirdness with DBXML. The doc() function works with HTTP as you would expect:
doc('http://example.com/videos.xml')But how does it work for the local filesystem? Well, the documentation has two suggestive, but misleading examples: file://path-to-document - found here, and myscheme://a/b/c - found in the [FAQ (What are the restrictions on document names?)|http://www.oracle.com/technology/products/berkeley-db/faq/xml_faq.html#18]. So I went:
doc('file:///C:/videos.xml') (: wrong :)
doc('file://C:/videos.xml') (: wrong :)
doc('file:/C:/videos.xml') (: wrong :)
doc('file:C:/videos.xml') (: finally ... looks weird, but works :)It didn't occur to me that despite the customary double slash shown in the examples in the documentation, you mustn't put any slash at all after the file: scheme!
Michael Ludwig
PS:
Maybe you could comment on how it is supposed to work? Just found that for a file in the current directory, I can use all of the following:
doc('file:u.xml')
doc('file:/u.xml')
doc('file://u.xml')
doc('file:///u.xml')
doc('file:////////////////////////////////u.xml')Edited by: miluas on Apr 27, 2009 6:58 PM
Edited by: miluas on Apr 29, 2009 9:33 AM

Answer 1

As far as Xerces is concerned, I don't think it is a bug. I don't think it's a non-conformance either. The file URI Xerces wants for Windows is conformant to the general URI scheme, as far as I can tell.
[RFC 1738 - Uniform Resource Locators (URL)|http://tools.ietf.org/html/rfc1738]
[RFC 3986 - Uniform Resource Identifier (URI): Generic Syntax|http://tools.ietf.org/html/rfc3986]
But I think it's a bug in the BDB XML documentation and FAQ, which I included links to in my original message, to suggest another, non-working syntax.
Michael Ludwig