I'm reading the TurnKey Linux 14 documentation and it states that in order to preseed values for an appliance, you have to write them to the file system before the machine boots for the first time.
The most obvious way to do this that I can think of, is to boot the VM to a Live CD and mount the file system in question in order to write the file.
Does VirtualBox contain another way of doing this? For instance using a bash utility of some sort to write an external file to the existing file system?
I believe there was a way to accomplish this on VMWare using vSphere, which is why I am asking.