diff --git a/lcl.c b/lcl.c
index 1e5d5d6..c0b9848 100644
--- a/lcl.c
+++ b/lcl.c
@@ -230,7 +230,7 @@ cl_parseopts(lua_State *L)
 
 	/* parameter type checking */
 	luaL_checktype(L, 1, LUA_TTABLE);
-	strcpy(optstring, (char *)luaL_checkstring(L, 2));
+	strlcpy(optstring, (char *)luaL_checkstring(L, 2), lua_rawlen(L, 2) * sizeof(char *));
 	luaL_checktype(L, 3, LUA_TFUNCTION);
 
 	argc = (int)lua_rawlen(L, 1) + 1; /* get argv length */