The API functions provided by Silk Performer work on handles that represent either a whole XML document, a single node or a list of nodes. Depending on the type of handle, there are different functions that can be used to operate on those type of nodes.
There are different ways to get a document handle. You can either load an existing document from a file, load an existing document from a valid XML string or create a new document from scratch. The methods responsible for this are XmlCreateDocument, XmlCreateDocumentFromFile and XmlCreateDocumentFromXml. All these functions return a handle to a document.