Fix markup where C include files get named in <...> form; bug reported by
Lorenzo M. Catucci <lorenzo@argon.roma2.infn.it>.
diff --git a/Doc/lib/libgrp.tex b/Doc/lib/libgrp.tex
index b15128d..4d1ab80 100644
--- a/Doc/lib/libgrp.tex
+++ b/Doc/lib/libgrp.tex
@@ -9,7 +9,7 @@
 It is available on all \UNIX{} versions.
 
 Group database entries are reported as 4-tuples containing the
-following items from the group database (see \file{<grp.h>}), in order:
+following items from the group database (see \code{<grp.h>}), in order:
 \code{gr_name},
 \code{gr_passwd},
 \code{gr_gid},