diff --git a/chap01/unix_list.c b/chap01/unix_list.c
index eeb5910..03213a8 100644
--- a/chap01/unix_list.c
+++ b/chap01/unix_list.c
@@ -34,7 +34,7 @@ int main() {
     struct ifaddrs *addresses;
 
     if (getifaddrs(&addresses) == -1) {
-        printf("getifaddrs call failed\n");
+        perror("getifaddrs call failed");
         return -1;
     }