diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex
index aeba94ac4d6..0d23bd703a4 100644
--- a/Doc/lib/libos.tex
+++ b/Doc/lib/libos.tex
@@ -326,7 +326,6 @@ translated into a corresponding call to \function{unsetenv()}; however,
 calls to \function{unsetenv()} don't update \code{os.environ}, so it is
 actually preferable to delete items of \code{os.environ}.
 \end{funcdesc}
-\end{funcdesc}
 
 \subsection{File Object Creation \label{os-newstreams}}