DRV_LOAD

The DRV_LOAD message requests a user-mode multimedia driver to perform post-load operations.

Parameters

dwDriverID

Specifies the driver instance identifier. This value is zero for the DRV_LOAD message.

hDriver

Driver handle.

uMsg

DRV_LOAD

lParam1

Not used. Set to zero.

lParam2

Not used. Set to zero.

Return Value

The driver should return a nonzero value if the operation succeeds. Otherwise it should return zero, which causes winmm.dll to unload the driver.

Comments

The DRV_LOAD message is one of the standard driver messages. A client sends the message by calling the driver’s DriverProc entry point, passing the specified parameter values.

A user mode driver is not loaded until the first time a client attempts to open a driver instance. Immediately after being loaded, a driver receives a DRV_LOAD message so it can handle load-time activities. These activities might include initializing libraries or loading additional resources.

After a user-mode driver instance has been opened, the driver remains loaded until all instances have been closed.

See Also

DRV_FREE