To illustrate both the construction of a kernel-mode driver and the use of soundlib.lib, the following sections examine the sample kernel-mode driver sndblst.sys. This driver supports the Creative Labs Sound Blaster card. It is called from the user-mode driver sndblst.dll, for waveform, mixer, and auxiliary I/O operations. For MIDI operations, sndblst.sys is called from the standard audio driver, mmdrv.dll. Source code for sndblst.sys, sndblst.dll, and mmdrv.dll are included with this DDK, at the directory paths listed in Sample Audio Drivers. When you read the topics within this section, it is helpful to refer to the source code for sndblst.sys.