Introduction to Changer Drivers

A changer driver controls the elements of a media library, or changer (sometimes called an autoloader, autochanger, or jukebox). In NT-based operating systems, a driver for a changer consists of the following:

• A system-supplied changer class driver provided as a library, mcd.lib, that provides functionality common to all changer drivers

• A device-specific miniclass driver, statically linked to mcd.lib, that provides routines called by the changer class driver to support a particular type of changer

This section describes the Windows changer driver model, and provides details for writing a new changer miniclass driver.