Re: [xml] libxml2 newbie question about the Reader API

[Daniel Veillard <veillard redhat com>]

On Thu, Feb 17, 2005 at 08:59:24PM +0100, Aron Stansvik wrote:
> Hello xml readers.
>
> Because of some peoples misuse of XML, I'm now writing a simple
> wxWidgets application that needs to process huge XML documents. I've
> tested that the libxml2 Reader API can handle the load well.
>
> Now I want my application to give some kind of progress feedback to
> the user. Is there a way to obtain the number of bytes read when using
> a Reader obtained using the simple xmlReaderForFile() function, or
> will I have to set up my own custom I/O handlers with
> xmlReaderForIO()? I can't find any example usage of this function
> anywhere, and I having a bit of a hard time deciphering how it
> actually works. Googling for "xmlReaderForIO" only gives 10 hits (!).
>
> My plan is to just stat() the file for it's size before processing it,
> and then use the number of bytes read to calculate progress, so all I
> need is the position in the input stream that libxml2 uses.

  There is number of simplifications in your approach, like external
parsed entities, encoding conversions.

  http://xmlsoft.org/html/libxml-parser.html#xmlByteConsumed
  From a normal parser you can call this. This is more complex
than you may think. I don't think on can get the parsr from a reader 
but the option exists.

> Greatful for any advice and examples of using custom I/O with the
> Reader API. I've looked at the custom I/O code samples at xmlsoft.org,

  It's like the I/O from other APIs !
   
    http://xmlsoft.org/xmlio.html#Example2
    http://xmlsoft.org/examples/index.html#InputOutput

Daniel

-- 
Daniel Veillard      | Red Hat Desktop team http://redhat.com/
veillard redhat com  | libxml GNOME XML XSLT toolkit  http://xmlsoft.org/
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