Cygwin may be the only way to stay sane while using Windows, but it has its own Unix-like notion for drive names, e.g., “/cygdrive/c/” instead of “c:“. Which is fine, except when you want to use both Java XML tools, which understand only the “c:” form, and Cygwin tools, which tend to understand only the “/cygdrive/c/” form.
The Cygwin xsltproc and xmllint complain when you use them with files containing Windows drive names in system identifiers, so the second time it happened, I wrote a simple XML catalog file to map the Windows drive names to the Cygwin paths.
Put this as the contents of /etc/xml/catalog (not catalog.xml!) and the Cygwin xsltproc, etc., will handle Windows drive names:
<?xml version="1.0"?>
<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
<rewriteSystem
systemIdStartString="file:///C:/"
rewritePrefix="file:///cygdrive/c/"/>
</catalog>
You will have to add a suitable rewriteSystem for each additional drive that you use.