--- a/siod/siod.cc
+++ b/siod/siod.cc
@@ -459,7 +459,7 @@ char **siod_variable_generator(char *text,int length)
     matches = walloc(char *,siod_llength(lmatches)+1);
     for (l=lmatches,i=0; l; l=cdr(l),i++)
 	matches[i] = wstrdup(PNAME(car(l)));
-    matches[i] = '\0';
+    *matches[i] = '\0';
 
     return matches;
 }
@@ -498,7 +498,7 @@ char **siod_command_generator (char *text,int length)
     matches = walloc(char *,siod_llength(lmatches)+1);
     for (l=lmatches,i=0; l; l=cdr(l),i++)
 	matches[i] = wstrdup(PNAME(car(l)));
-    matches[i] = '\0';
+    *matches[i] = '\0';
 
     return matches;
 }