diff --git a/docs/examples/post-callback.c b/docs/examples/post-callback.c
index 1a044808a..e3f37c4ae 100644
--- a/docs/examples/post-callback.c
+++ b/docs/examples/post-callback.c
@@ -36,7 +36,7 @@ static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *userp)
     return 1;                        /* we return 1 byte at a time! */
   }
 
-  return -1;                         /* no more data left to deliver */
+  return 0;                          /* no more data left to deliver */
 }
 
 int main(void)