[xml] xml output streaming and c14n

["Prashant R" <ramapra gmail com>]

I have a requirement, where I would not want to have the entire xml data in memory and preferably writing out canonicalized XML to IO .

I had a few questions to understand this better 

I was planning on doing the following 

• creating an OutputBuffer using the API - xmlOutputBufferCreateIO (xmlOutputWriteCallback iowrite, xmlOutputCloseCallback ioclose, void * ioctx, xmlCharEncodingHandlerPtr encoder) // as I need to stream to I/O
  
• then  using the API  xmlTextWriterPtr xmlNewTextWriter (xmlOutputBufferPtr out) , to create an xmlWriterObject
  

• write out the xml nodes based on my application logic
  

Quesions

1. When will the actual write ( to I/O , in my case )occur ? Could it occur before the entire document is fully completed?

2. Is there a way where I could stream xml data directly to IO without building the tree in memory ( using DOM API's)?

3 If there is a way to do (2) , then is there a way to specify that the output be canonicalized ?

Thanks in advance