Trap SIGINT, etc and release used resources
diff --git a/tools/build_usb_boot.sh b/tools/build_usb_boot.sh
index fc5e969..e4dabc0 100755
--- a/tools/build_usb_boot.sh
+++ b/tools/build_usb_boot.sh
@@ -11,6 +11,26 @@
OPWD=`pwd`
PROGDIR=`dirname $0`
+# Clean up any resources that may be in use
+cleanup() {
+ set +o errexit
+
+ # Mop up temporary files
+ if [ -n "$DEST_DEV" ]; then
+ umount $DEST_DIR
+ rmdir $DEST_DIR
+ fi
+ if [ -n "$MNTDIR" -a -d "$MNTDIR" ]; then
+ umount $MNTDIR
+ rmdir $MNTDIR
+ fi
+
+ # Kill ourselves to signal any calling process
+ trap 2; kill -2 $$
+}
+
+trap cleanup SIGHUP SIGINT SIGTERM
+
if [ -b $DEST_DIR ]; then
# We have a block device, install syslinux and mount it
DEST_DEV=$DEST_DIR