diff --git a/reference/strings/functions/sscanf.xml b/reference/strings/functions/sscanf.xml
index a29c70d6b5..5dd8b69bc7 100644
--- a/reference/strings/functions/sscanf.xml
+++ b/reference/strings/functions/sscanf.xml
@@ -83,11 +83,15 @@
  <refsect1 role="returnvalues">
   &reftitle.returnvalues;
   <para>
-   If only
-   two parameters were passed to this function, the values parsed
-   will be returned as an array. Otherwise, if optional parameters are passed,
-   the function will return the number of assigned values. The optional
-   parameters must be passed by reference.
+   If only two parameters were passed to this function, the values parsed will
+   be returned as an array. Otherwise, if optional parameters are passed, the
+   function will return the number of assigned values. The optional parameters
+   must be passed by reference.
+  </para>
+  <para>
+   If there are more substrings expected in the <parameter>format</parameter>
+   than there are available within <parameter>str</parameter>,
+   <literal>-1</literal> will be returned.
   </para>
  </refsect1>