KSLN, Type
Selects those keypoints associated with the selected nodes.
TypeLabel identifying the type of keypoint select:
S  | —  | Select a new set (default).  | 
R  | —  | Reselect a set from the current set.  | 
A  | —  | Additionally select a set and extend the current set.  | 
U  | —  | Unselect a set from the current set.  |