+AC_CHECK_HEADERS(signal.h termios.h sys/errno.h)
+
+
+case "$host" in
+ *mingw* | *cygwin*)
+ AM_CONDITIONAL(WIN32_PKG, true)
+ AM_CONDITIONAL(MACOSX_PKG, false)
+ ;;
+ *darwin*)
+ AM_CONDITIONAL(WIN32_PKG, false)
+ AM_CONDITIONAL(MACOSX_PKG, true)
+ ;;
+ *)
+ AM_CONDITIONAL(WIN32_PKG, false)
+ AM_CONDITIONAL(MACOSX_PKG, false)
+ ;;
+esac
+
+