To define a virtual device based on a real device
When you execute the MEL script, a virtual device is defined with the same name as the real device. If you have attachment scripts, they will work with the virtual device without any changes.
You can use virtual devices to import numeric data into Maya. In many cases, you can use the movIn command. However, if you are using filters or resamplers, we recommend using a virtual device.
For more information, search the Help > MEL Command Reference documentation for the defineVirtualDevice command.
To read data into a virtual device