* guaranteed to be writable. @size can be set to -1 to return a copy
* from @offset to the end of the memory region.
*
- * Returns: a new #GstMemory.
+ * Returns: (transfer full) (nullable): a new copy of @mem if the copy succeeded, %NULL otherwise.
*/
GstMemory *
gst_memory_copy (GstMemory * mem, gssize offset, gssize size)