Use \withsubitem{} for indexing functions from other modules. This fixes
things in the index.
diff --git a/Doc/lib/libposix.tex b/Doc/lib/libposix.tex
index 1a62bba..467195f 100644
--- a/Doc/lib/libposix.tex
+++ b/Doc/lib/libposix.tex
@@ -440,10 +440,10 @@
\var{machine})}. Some systems truncate the nodename to 8
characters or to the leading component; a better way to get the
hostname is \function{socket.gethostname()}%
-\index{gethostname()@\idxcode{gethostname()} (in module socket)}
+\withsubitem{(in module socket)}{\ttindex{gethostname()}}
or even
\code{socket.gethostbyaddr(socket.gethostname())}%
-\index{gethostbyaddr()@\idxcode{gethostbyaddr()} (in module socket)}.
+\withsubitem{(in module socket)}{\ttindex{gethostbyaddr()}}.
(Not on MS-DOS, nor on older \UNIX{} systems.)
\end{funcdesc}