Remove mentionings of DOS.
diff --git a/Doc/doc/doc.tex b/Doc/doc/doc.tex
index b88350f..22f9d13 100644
--- a/Doc/doc/doc.tex
+++ b/Doc/doc/doc.tex
@@ -927,8 +927,8 @@
     \begin{macrodesc}{program}{\p{name}}
       The name of an executable program.  This may differ from the
       file name for the executable for some platforms.  In particular, 
-      the \file{.exe} (or other) extension should be omitted for DOS
-      and Windows programs.
+      the \file{.exe} (or other) extension should be omitted for 
+      Windows programs.
     \end{macrodesc}
 
     \begin{macrodesc}{programopt}{\p{option}}