The GetCLSID method of the IUrlAccessor interface returns the CLSID of a document type.
pClsid [out] Pointer to a CLSID that contains the class ID from the registry for the document type. This is used for items with special IFilter associations to indicate the appropriate IFilter to use for that embedded document.
For a list of error messages returned by Microsoft Office SharePoint Portal Server 2003 protocol handlers, see Protocol Handler Error Messages.
If you do not provide an implementation for the GetDocFormat or GetCLSID methods, the Filter Daemon makes the association between the item's file extension and the Multipurpose Internet Mail Extensions (MIME) "Content Type." Implement this method when the extensions you are dealing with are supposed to have a different association from what is indicated by the file extension or content type. For example if ".doc" items in your content source are not associated with Microsoft Office Word, this method should return the class ID of the appropriate document source.
Platforms: Microsoft Windows Server 2003