DRIVERPROC callback function (mmiscapi.h)

Article
02/22/2024

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

Syntax

DRIVERPROC Driverproc;

LRESULT Driverproc(
  DWORD_PTR unnamedParam1,
  HDRVR unnamedParam2,
  UINT unnamedParam3,
  LPARAM unnamedParam4,
  LPARAM unnamedParam5
)
{...}

Parameters

unnamedParam1

Identifier of the installable driver.

unnamedParam2

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

unnamedParam3

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.

unnamedParam4

32-bit message-specific value.

unnamedParam5

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

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	mmiscapi.h (include Mmiscapi.h, Windows.h)