+# use Xdisplay only if present and running under X:
+display_info() {
+if is_installed xterm && test -n "$DISPLAY" ; then
+ xterm -T 'Sorry :(' -e "dialog --msgbox \"$1\" 0 0"
+else
+ printf '%s\n' "$1">&2
+fi
+}
+
+if [ -z "$1" -o "$1" = '-h' -o "$1" = '--help' ] ; then
+ usage
+ exit 1
+fi
+
+if [ "$1" = '-p' ] ; then
+ if [ -z "$2" ] ; then
+ usage
+ exit 1
+ else
+ PROG="$2"
+ shift ; shift
+ fi