--- a/nuc-fw/cfgmagic/functions	Sun Aug 25 19:27:40 2013 +0000
+++ b/nuc-fw/cfgmagic/functions	Sun Aug 25 20:13:24 2013 +0000
@@ -46,7 +46,13 @@
 		echo "export_to_c: wrong number of arguments" 1>&2
 		exit 1
 	fi
-	c_export_list="$c_export_list $1"
+	case "$c_export_list" in
+		*" $1 "* | *" $1")
+			;;
+		*)
+			c_export_list="$c_export_list $1"
+			;;
+	esac
 }
 
 export_to_mk() {
@@ -55,7 +61,13 @@
 		echo "export_to_mk: wrong number of arguments" 1>&2
 		exit 1
 	fi
-	mk_export_list="$mk_export_list $1"
+	case "$mk_export_list" in
+		*" $1 "* | *" $1")
+			;;
+		*)
+			mk_export_list="$mk_export_list $1"
+			;;
+	esac
 }
 
 export_to_m4() {
@@ -64,5 +76,11 @@
 		echo "export_to_m4: wrong number of arguments" 1>&2
 		exit 1
 	fi
-	m4_export_list="$m4_export_list $1"
+	case "$m4_export_list" in
+		*" $1 "* | *" $1")
+			;;
+		*)
+			m4_export_list="$m4_export_list $1"
+			;;
+	esac
 }