No AC power cord for Laptop. I solved the problem.

Somehow I forgot my AC power cord for my laptop. I did bring my AC adapter that works off of DC for use on a plane or car.  So it seemed like all I could do was charge the laptop's battery in the truck or use it while in the truck.

I thought that leaving the laptop charging in the truck all night might run down the truck's battery.  So, I just connected the 12V battery charger for my camper batteries to the laptop's cigarette lighter plug. 

The battery charger provides just enough power to run the laptop.