Supplying DTD for validation when using Reader API
(Opening this here since my issue at https://bugzilla.gnome.org/show_bug.cgi?id=169375 was closed as OBSOLETE during migration to GitLab)
The issue is that there should be a way to specify an external DTD to be used for validation when using the Reader API (similar to posteriori validation when using the DOM API, but occurring at the time of reading, without having to read the whole document into memory).
This was further discussed on the mailing list in 2011: https://mail.gnome.org/archives/xml/2011-July/msg00005.html
@veillard suggested in that thread that writing a custom I/O which injects a DOCTYPE referencing the DTD of choice would be the easiest/safest option: https://mail.gnome.org/archives/xml/2011-July/msg00012.html
A question was raised whether that approach could also handle the case where the DTD referenced in an existing DOCTYPE needs to be replaced.
@veillard also suggested "The real solution would be to allow DTD validation from a preparsed DTD at the xmlreader level directly.", so this issue is to track potential future work on that.
Assigning @veillard since he was the assignee on the original Bugzilla bug, but I realize that a lot of things may have happened since 2005, so feel free to un-assign yourself :)