+### use option --enable-interop to turn on use of bindings used for interop
+AC_MSG_CHECKING(if you want interop bindings)
+AC_ARG_ENABLE(interop,
+ [ --enable-interop compile-in experimental interop bindings],
+ [with_exp_interop=$enableval],
+ [with_exp_interop=no])
+AC_MSG_RESULT($with_exp_interop)
+
+NCURSES_INTEROP_FUNCS=0
+test "$with_exp_interop" = yes && NCURSES_INTEROP_FUNCS=1
+AC_SUBST(NCURSES_INTEROP_FUNCS)
+