DriverProc
Processes driver messages for the installable driver. DriverProc is a driver-supplied function.
LONG DriverProc(
DWORDdwDriverId,
HDRVRhdrvr,
UINTmsg,
LONGlParam1,
LONGlParam2);
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
** Windows NT/2000:** Requires Windows NT 3.1 or later.
** Windows 95/98:** Requires Windows 95 or later.
** Header:** Declared in Mmsystem.h.
See Also