Get rid of math mode in some places.
diff --git a/Doc/mac/libmactcp.tex b/Doc/mac/libmactcp.tex
index 4d6d5ba..a16afc8 100644
--- a/Doc/mac/libmactcp.tex
+++ b/Doc/mac/libmactcp.tex
@@ -164,7 +164,7 @@
 \renewcommand{\indexsubitem}{(UDP stream method)}
 
 \begin{funcdesc}{Read}{timeout}
-Read a datagram, waiting at most \var{timeout} seconds ($-1$ is
+Read a datagram, waiting at most \var{timeout} seconds (-1 is
 infinite).  Return the data.
 \end{funcdesc}