--- a/wrap.c
+++ b/wrap.c
@@ -105,7 +105,7 @@ int main(int argc, char **argv)
 	{
 	*wp = 0;
 	putchar('\n');
-	printf(wbuf);
+	printf("%s", wbuf);
 	putchar(c);
 	putchar('\n');
 	wp = wbuf, ll = wl = 0;
@@ -123,7 +123,7 @@ int main(int argc, char **argv)
 	{
 	*wp = 0;
 	if(ll) putchar(' '), ll++;
-	printf(wbuf);
+	printf("%s", wbuf);
 	ll += wl;
 	wl = 0,	wp = wbuf;
 	}
@@ -131,7 +131,7 @@ int main(int argc, char **argv)
 	{
 	*wp = 0;
 	putchar('\n');
-	printf(wbuf);
+	printf("%s", wbuf);
 	ll = wl;
 	wl = 0, wp = wbuf;
 	}
@@ -148,7 +148,7 @@ int main(int argc, char **argv)
       if(ll) putchar(' ');
       }
     else putchar('\n');
-    printf(wbuf);
+    printf("%s", wbuf);
     }
   putchar('\n');
   free(wbuf);