I want to copy arbitrary files from a Pokini Tab A5 running Windows Embedded 8.1 Industry Pro to a laptop or desktop computer running anything from Windows Vista to Windows 8.1 (or even 10). This should all happen programmatically or at least in an automatic way (e.g. calling a program from the command line).
Unfortunately, Wi-Fi or Bluetooth is not an acceptable solution for my use case. However, installing software is allowed on both the computer and the Pokini Tab A5. Preferably written in Java but C, C++ and C# is also fine.
My current approach is using this cable (which goes by the name direct link cable, bridge cable, host-to-host and many others) which allows the transfer of files using supported software such as PCLinq5 (provided by the cable itself) or Windows Easy Transfer (deprecated since Windows 8.1). However, both these tools can not be used in programmatic way.
The only thing I found on the web is this project on GitHub but it doesn't include source code at all and doesn't look like it's free software which is basically a must-have for me. I also found this post on Stack Overflow but using WinUSB seems only useful to me when I know the exact protocol used by the hardware built into the cable.
Is using the cable a dead end? – Are there any other approaches?
The cable is not a dead end! – I was able to transmit data using USB bulk transfer. With this, I can probably implement my own custom file transfer protocol.
This most important part was figuring out which controller drives the data transfer cable. In my case it is a controller not unlike this one. The data sheet contains all information that is required to establish a connection between two hosts (e.g. interfaces and endpoints).