Remove all uses of \sectcode; we can now use logical markup everywhere.
diff --git a/Doc/lib/libposix.tex b/Doc/lib/libposix.tex
index 261c6aa..071cf56 100644
--- a/Doc/lib/libposix.tex
+++ b/Doc/lib/libposix.tex
@@ -1,4 +1,4 @@
-\section{Built-in Module \sectcode{posix}}
+\section{Built-in Module \module{posix}}
 \label{module-posix}
 \bimodindex{posix}