diff --git a/test.block b/test.block
index 781560dee1..622a66037f 100644
--- a/test.block
+++ b/test.block
@@ -2,9 +2,17 @@
 #
 # test.block - run udev(8) on each block device in /sys/block
 
+if [ $# = "0" ] ; then
+	echo
+	echo "usage: $0 <action>"
+	echo "where <action> is \"add\" or \"remove\""
+	echo
+	exit 1
+fi
+
 SYSFSDIR=/sys		# change this for a nonstand sysfs mount point
 BIN=./udev		# location of your udev binary
-export ACTION=add	# 'add' or 'remove'
+export ACTION=$1	# 'add' or 'remove'
 
 for i in ${SYSFSDIR}/block/*; do
 	# add each drive
diff --git a/test.tty b/test.tty
index ec8b1d0404..d5e2d6715d 100644
--- a/test.tty
+++ b/test.tty
@@ -2,9 +2,17 @@
 #
 # test.tty - run udev(8) on each tty device in /sys/class/tty
 
+if [ $# = "0" ] ; then
+	echo
+	echo "usage: $0 <action>"
+	echo "where <action> is \"add\" or \"remove\""
+	echo
+	exit 1
+fi
+
 SYSFSDIR=/sys		# change this for a nonstand sysfs mount point
 BIN=./udev		# location of your udev binary
-export ACTION=add	# 'add' or 'remove'
+export ACTION=$1	# 'add' or 'remove'
 
 for i in ${SYSFSDIR}/class/tty/*; do
 	export DEVPATH="/"`echo $i | cut --delimiter='/' --fields=3-`