+ 6.4 (Dec 31, 2022)
+ Interface changes:
+
+ + none
+
+ Added extensions:
+
+ + none
+
+ Added internal functions (other than "_sp" variants):
+
+ + add _nc_free_termtype1 and _nc_free_tparm, for memory-leaks
+
+ Removed internal functions:
+
+ + none
+
+ Modified internal functions:
+
+ + none
+