@@ -203,8 +203,8 @@ static struct option longopts[] = {

 int main(int argc, char *argv[]){

 	int benchmark = 0;

-	char *initial_query = NULL;

-	char *tty_filename = "/dev/tty";

+	const char *initial_query = NULL;

+	const char *tty_filename = "/dev/tty";

 	char c;

 	while((c = getopt_long(argc, argv, "vhse:l:t:p:", longopts, NULL)) != -1){

 		switch(c){