Adjusted to use the new module synopsis support macros.
diff --git a/Doc/lib/libgrp.tex b/Doc/lib/libgrp.tex
index 551171b..986c831 100644
--- a/Doc/lib/libgrp.tex
+++ b/Doc/lib/libgrp.tex
@@ -1,7 +1,9 @@
 \section{Built-in Module \module{grp}}
-\label{module-grp}
+\declaremodule{builtin}{grp}
 
-\bimodindex{grp}
+
+\modulesynopsis{The group database (\function{getgrnam()} and friends).}
+
 This module provides access to the \UNIX{} group database.
 It is available on all \UNIX{} versions.