RE: [xml-dev] Case sensitivity of system identifiers

["Michael Kay" <mike@saxonica.com>]

Title: Case sensitivity of system identifiers

The system identifier in XML is actually a URI. Two URIs that differ in case are different URIs, but that doesn't stop them referring to the same resource (just as a/s.xml and b/s.xml might refer to the same resource if a and b are different names for the same directory). In a document containing <!DOCTYPE sampledocument SYSTEM "sampledocument.DTD">   the validity of the document relies on the fact that the relative URI sampledocument.DTD can be dereferenced to deliver a resource, and this is obviously going to vary depending on where the document is located: it will work in an environment where there is a file retrievable by the name sampledocument.DTD, and it won't work in an environment where there isn't.

 

 

Michael Kay

http://www.saxonica.com/

 

 

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From: Moser Thomas M. (KSEB 321) [mailto:moser.thomas@credit-suisse.com]
Sent: 10 January 2007 10:09
To: xml-dev@lists.xml.org
Subject: [xml-dev] Case sensitivity of system identifiers

Hi,

Considering a DTD "sampledocument.dtd" and two documents, one starting with:

<!DOCTYPE sampledocument SYSTEM "sampledocument.dtd">
...

the other one starting with:

<!DOCTYPE sampledocument SYSTEM "sampledocument.DTD">
...

The two xml documents only differ by the case of the file name of the refered local DTD. On a Windows host both xml documents are regarded as valid (XMLSpy), on a UNIX host the second document is not, because the validator cannot find the DTD (UNIX file system is case-sensitive).

XML as such is case-sensitive, but are the values of system identifiers case-sensitive as well?

I did not find any explicit hint on that, can anybody point me to where this matter might be specified?

Thanks a lot

Thomas.