Modifies a pointer to a GstQuery to point to a different GstQuery. The
modification is done atomically (so this is useful for ensuring thread safety
in some cases), and the reference counts are updated appropriately (the old
query is unreffed, the new one is reffed).
Either new_query or the GstQuery pointed to by old_query may be NULL.
Modifies a pointer to a GstQuery to point to a different GstQuery. The modification is done atomically (so this is useful for ensuring thread safety in some cases), and the reference counts are updated appropriately (the old query is unreffed, the new one is reffed). Either new_query or the GstQuery pointed to by old_query may be NULL.