diff --git a/cryptobox b/cryptobox
index 3233016..a8bf2d2 100755
--- a/cryptobox
+++ b/cryptobox
@@ -10,85 +10,76 @@
 #                                                            #
 ##############################################################
 
-NAME=`echo $0 | grep -o -e "[^\/]*$"`
+NAME=`echo "$0" | grep -o -e "[^\/]*$"`
 
-# Check for root
-[[ "$UID" -ne 0 ]] && (echo -e "Error: Please run this script with root permissions\n"; exit 1)
-
-# Check dependencies
-[[ `type -P dd` ]] || (echo "Error: The 'dd' program is missing"; exit 1)
-[[ `type -P losetup` ]] || (echo "Error: The 'losetup' program is missing"; exit 1)
-[[ `type -P cryptsetup` ]] || (echo "Error: The 'cryptsetup' program is missing"; exit 1)
-[[ `type -P mkfs` ]] || (echo "Error: The 'mkfs' program is missing"; exit 1)
-
-# Load modules if they aren't present
-[[ `lsmod | grep loop` ]] || echo "loading 'loop' module"; modprobe loop || (echo "Error: failed to load 'loop' module"; exit 1)
-[[ `lsmod | grep dm_mod` ]] || echo "loading 'dm_mod' module"; modprobe dm_mod || (echo "Error: failed to load 'dm_mod' module"; exit 1)
+function errorquit {
+    echo -e "Error: $1"
+    [[ "$1" = "syntax" ]] && (echo; usage)
+    exit 1
+}
 
 function usage {
     echo -e "${NAME}: create and mount encrypted images\n"
-    echo "Usage: ${NAME} option arguments"
+    echo "Usage: $NAME option arguments"
     echo -e "\tc (create) -> $NAME c filename.img filesystem size-in-mb"
     echo -e "\tm (mount) -> $NAME m filename.img /mount/point"
     echo -e "\tu (umount) -> $NAME u /mount/point"
 }
 
+# Check for root
+[[ "$UID" -ne 0 ]] && errorquit "run with root permission\n"
+
+# Check dependencies
+[[ `type -P dd` ]] || errorquit "Error: The 'dd' program is missing"
+[[ `type -P losetup` ]] || errorquit "Error: The 'losetup' program is missing"
+[[ `type -P cryptsetup` ]] || errorquit "Error: The 'cryptsetup' program is missing"
+[[ `type -P mkfs` ]] || errorquit "Error: The 'mkfs' program is missing"
+
+# Load modules if they aren't present
+[[ `lsmod | grep loop` ]] || echo "loading 'loop' module"; modprobe loop || errorquit "Error: failed to load 'loop' module"
+[[ `lsmod | grep dm_mod` ]] || echo "loading 'dm_mod' module"; modprobe dm_mod || errorquit "Error: failed to load 'dm_mod' module"
+
 if [ -z "$1" ]; then
-    usage
-    exit 1
+    usage; exit 1
 elif [ ! "$1" = "c" -a ! "$1" = "m" -a ! "$1" = "u" ]; then
-    echo "syntax error"
-    usage
-    exit 1
+    errorquit "syntax"
 fi
 
 case "$1" in
-    "c")
-        if [ -z "$2" -o -z "$3" -o -z "$4" ]; then
-            echo "syntax error"
-            usage
-            exit 1
-        fi
-        if [ -f "$2" ]; then
-            echo "error: $2 already exists"
-            exit 1
-        fi
+    c)
+        if [ -z "$2" -o -z "$3" -o -z "$4" ]; then errorquit "syntax"; fi
+        [[ -f "$2" ]] && errorquit "$2 already exists"
         LOOPDEV=`losetup -f`
         CONTAINER=`echo "$2" | sed s/"[^\/]*\/"//g | sed s/"\.".*$//g`
-        dd bs=1M count="$4" if=/dev/urandom of="$2"
-        losetup $LOOPDEV "$2"
-        cryptsetup -c aes-xts-plain -y -s 512 luksFormat $LOOPDEV
-        cryptsetup luksOpen $LOOPDEV $CONTAINER
-        mkfs -t "$3" /dev/mapper/$CONTAINER || echo "error: mkfs failed for filesystem type: $3"
-        cryptsetup luksClose $CONTAINER
-        losetup -d $LOOPDEV
+        dd bs=1M count="$4" if=/dev/urandom of="$2" || errorquit "couldn't create create image file"
+        losetup "$LOOPDEV" "$2" || errorquit "couldn't setup loop device (${LOOPDEV})"
+        cryptsetup -c aes-xts-plain -y -s 512 luksFormat "$LOOPDEV" || errorquit "couldn't encrypt image file"
+        cryptsetup luksOpen "$LOOPDEV" "$CONTAINER" || errorquit "couldn't decrypt $CONTAINER"
+        mkfs -t "$3" "/dev/mapper/${CONTAINER}" || errorquit "mkfs failed for filesystem type: $3"
+        cryptsetup luksClose "$CONTAINER" || errorquit "couldn't close encryption for $CONTAINER"
+        sleep 1
+        losetup -d "$LOOPDEV" || errorquit "couldn't close loop device (${LOOPDEV})"
         ;;
-    "m")
-        if [ -z "$2" -o -z "$3" ]; then echo -e "Error: syntax\n"; usage; exit 1; fi
-        [[ ! -f "$2" ]] && (echo "Error: $2 does not exist"; exit 1)
-        [[ -d "$3" ]] || (echo "Error: $3 does not exist"; exit 1)
+    m)
+        if [ -z "$2" -o -z "$3" ]; then errorquit "syntax"; fi
+        [[ ! -f "$2" ]] && errorquit "$2 does not exist"
+        [[ -d "$3" ]] || errorquit "$3 does not exist"
         LOOPDEV=$(losetup -f)
-        CONTAINER=$(echo $LOOPDEV | sed s/"[^\/]*\/"//g | sed s/"\.".*$//g)
-        losetup $LOOPDEV "$2"
-        cryptsetup luksOpen $LOOPDEV $CONTAINER
-        mount /dev/mapper/$CONTAINER "$3"
+        CONTAINER=$(echo "$LOOPDEV" | sed s/"[^\/]*\/"//g | sed s/"\.".*$//g)
+        losetup "$LOOPDEV" "$2" || errorquit "couldn't setup loop device (${LOOPDEV})"
+        cryptsetup luksOpen "$LOOPDEV" "$CONTAINER" || errorquit "couldn't decrypt $CONTAINER"
+        mount "/dev/mapper/${CONTAINER}" "$3" || errorquit "couldn't mount /dev/mapper/${CONTAINER} on $3"
         ;;
-    "u")
-        if [ -z "$2" ]; then
-            echo "syntax error"
-            usage
-            exit 1
-        fi
+    u)
+        if [ -z "$2" ]; then errorquit "syntax"; fi
         MOUNT=`mount | grep $(echo "$2" | sed s/"\/"$//)`
-        if [ -z "$MOUNT" ]; then
-            echo "error: $2 is not mounted"
-            exit 1
-        fi
-        LOOPDEV=`echo $MOUNT | sed s/\ .*//g | sed s/"\/mapper"//`
-        CONTAINER=`echo $LOOPDEV | sed s/"[^\/]*\/"//g | sed s/"\.".*$//g`
-        umount "$2"
-        cryptsetup luksClose $CONTAINER
-        losetup -d $LOOPDEV
+        [[ -z "$MOUNT" ]] && errorquit "$2 is not mounted"
+        LOOPDEV=`echo "$MOUNT" | sed s/\ .*//g | sed s/"\/mapper"//`
+        CONTAINER=`echo "$LOOPDEV" | sed s/"[^\/]*\/"//g | sed s/"\.".*$//g`
+        umount "$2" || errorquit "Couldn't unmount $2"
+        cryptsetup luksClose "$CONTAINER" || errorquit "couldn't close encryption for $CONTAINER"
+        sleep 1
+        losetup -d "$LOOPDEV" || errorquit "couldn't close loop device (${LOOPDEV})"
         ;;
     generic)
         usage