DriverProc function pointer

Processes driver messages for the installable driver. DriverProc is a driver-supplied function.

Syntax

typedef LRESULT ( CALLBACK *DRIVERPROC)(
   DWORD_PTR dwDriverId,
   HDRVR     hdrvr,
   UINT      msg,
   LONG      lParam1,
   LONG      lParam2
);

Parameters

• dwDriverId
  Identifier of the installable driver.

• hdrvr
  Handle of the installable driver instance. Each instance of the installable driver has a unique handle.

• msg
  Driver message value. It can be a custom value or one of these standard values:

  Value	Meaning
  DRV_CLOSE	Notifies the driver that it should decrement its usage count and unload the driver if the count is zero.
  DRV_CONFIGURE	Notifies the driver that it should display a configuration dialog box. This message is sent only if the driver returns a nonzero value when processing the DRV_QUERYCONFIGURE message.
  DRV_DISABLE	Notifies the driver that its allocated memory is about to be freed.
  DRV_ENABLE	Notifies the driver that it has been loaded or reloaded or that Windows has been enabled.
  DRV_FREE	Notifies the driver that it will be discarded.
  DRV_INSTALL	Notifies the driver that it has been successfully installed.
  DRV_LOAD	Notifies the driver that it has been successfully loaded.
  DRV_OPEN	Notifies the driver that it is about to be opened.
  DRV_POWER	Notifies the driver that the device's power source is about to be turned on or off.
  DRV_QUERYCONFIGURE	Directs the driver to specify whether it supports the DRV_CONFIGURE message.
  DRV_REMOVE	Notifies the driver that it is about to be removed from the system.

   

• lParam1
  32-bit message-specific value.

• lParam2
  32-bit message-specific value.

Return value

Returns nonzero if successful or zero otherwise.

Remarks

When msg is DRV_OPEN, lParam1 is the string following the driver filename from the SYSTEM.INI file and lParam2 is the value given as the lParam parameter in a call to the OpenDriver function.

When msg is DRV_CLOSE, lParam1 and lParam2 are the same values as the lParam1 and lParam2 parameters in a call to the CloseDriver function.

Requirements

See also

Installable Drivers

Driver Functions