Running sudo early in order to get the possible password prompt

xorriso-dd-target/xorriso-dd-target

@@ -230,8 +230,17 @@ arg_interpreter() {
     have_su_power=y
   elif test -n "$with_sudo"
   then
+    echo "Testing sudo to possibly get password prompting done now:"
+    if sudo $lsblk_cmd -h >/dev/null
+    then
+      echo "sudo $lsblk_cmd seems ok."
+      echo
       sudo_cmd=sudo
       have_su_power=y
+    else
+      echo "FAILURE: Cannot execute program $lsblk_cmd by sudo" >&2
+      exit 11
+    fi
   fi
 }
 
@@ -603,6 +612,7 @@ then
   if test -n "$dummy_force" -a -n "$dummy_run" -a "$num_cand" -ne 1 
   then
     # -dummy_force in a situation where the program would normally refuse
+    echo
     echo "Overriding any advice because of -dummy_force"
     candidates="$devs"
     num_cand=1