- GstReservedvoid*[4] GstReserved; 
- Undocumented in source. 
- allocGstFlowReturn function(GstPushSrc* src, GstBuffer** buf) alloc; 
- createGstFlowReturn function(GstPushSrc* src, GstBuffer** buf) create; 
- fillGstFlowReturn function(GstPushSrc* src, GstBuffer* buf) fill; 
- parentClassGstBaseSrcClass parentClass; 
Subclasses can override any of the available virtual methods or not, as needed. At the minimum, the @fill method should be overridden to produce buffers.