Made changes to -plug_test step 3

xorriso-dd-target/xorriso-dd-target

@@ -252,13 +252,15 @@ plug_in_watcher() {
   echo >&2
   echo "Step 1:" >&2
   echo "Please make sure that the desired target device is plugged _out_ now." >&2
+  echo "If it is currently plugged in, make sure to unmount all its fileystems" >&2
+  echo "and then unplug it." >&2
   echo "Press the Enter key when ready." >&2
   read dummy
   old_device_list=' '$($lsblk_cmd -d -n -o NAME  | grep -v '^sr[0-9]' | grep -v '^fd[0-9]' | tr '\n\r' '  ')' '
 
 # <<< Mock-up to save USB socket wear-off by erasing items from old_device_list
 # <<< Their presence in new_device_list will let them appear as fresh plugs
-# old_device_list=' '$(echo -n $old_device_list | sed -e 's/sd[e-f]//')' '
+# old_device_list=' '$(echo -n $old_device_list | sed -e 's/sde//')' '
 
   echo "Found and noted as _not_ desired: $old_device_list" >&2
   echo >&2
@@ -653,11 +655,18 @@ then
         echo "Step 3:" >&2
         if test -n "$dummy_run"
         then
-          echo "This would be the last chance to abort. Press Enter to see -dummy report." >&2
+          echo "This would be the last chance to abort. Enter the word 'yes' to see -dummy report." >&2
         else
-          echo "Last chance to abort. Press Enter to start REAL WRITING." >&2
+          echo "Last chance to abort. Enter the word 'yes' to start REAL WRITING." >&2
         fi
         read dummy
+        if test "$dummy" = "yes" -o "$dummy" = "'yes'" -o "$dummy" = '"yes"'
+        then
+          dummy=dummy
+        else
+          echo "WRITE RUN PREVENTED by user input '$dummy'." >&2
+          exit 12  
+        fi
       fi
       write_image "$image_file" $candidates
       exit $?