Do the right magic to make \UNIX{} get sorted correctly in the index.
diff --git a/Doc/libfcntl.tex b/Doc/libfcntl.tex
index 15aeec2..5dab283 100644
--- a/Doc/libfcntl.tex
+++ b/Doc/libfcntl.tex
@@ -1,8 +1,8 @@
% Manual text by Jaap Vermeulen
\section{Built-in Module \sectcode{fcntl}}
\bimodindex{fcntl}
-\indexii{\UNIX{}}{file control}
-\indexii{\UNIX{}}{I/O control}
+\indexii{UNIX@\UNIX{}}{file control}
+\indexii{UNIX@\UNIX{}}{I/O control}
This module performs file control and I/O control on file descriptors.
It is an interface to the \dfn{fcntl()} and \dfn{ioctl()} \UNIX{} routines.