Incorporate bug fixes from Plan 9.

include/regexp9.h

diff --git a/include/regexp9.h b/include/regexp9.h
index 382d246..b241712 100644
--- a/include/regexp9.h
+++ b/include/regexp9.h
@@ -69,7 +69,7 @@
 extern void	regsub9(char*, char*, int, Resub*, int);
 
 extern int	rregexec9(Reprog*, Rune*, Resub*, int);
-extern void	rregsub9(Rune*, Rune*, Resub*, int);
+extern void	rregsub9(Rune*, Rune*, int, Resub*, int);
 
 /*
  * Darwin simply cannot handle having routines that