IoGetDriverObjectExtension function (wdm.h)

The IoGetDriverObjectExtension routine retrieves a previously allocated per-driver context area.

Syntax

__drv_aliasesMem PVOID IoGetDriverObjectExtension(
  [in] PDRIVER_OBJECT DriverObject,
  [in] PVOID          ClientIdentificationAddress
);

Parameters

[in] DriverObject

Specifies the driver object with which the context area is associated.

[in] ClientIdentificationAddress

Specifies the unique identifier, provided when it was allocated, of the context area to be retrieved.

Return value

IoGetDriverObjectExtension returns a pointer to the context area, if any or returns NULL.

Remarks

Drivers call IoGetDriverObjectExtension to retrieve a pointer to a previously allocated extension area.

Requirements

   
Minimum supported client Available starting with Windows 2000.
Target Platform Universal
Header wdm.h (include Wdm.h, Ntddk.h, Ntifs.h)
Library NtosKrnl.lib
DLL NtosKrnl.exe
IRQL <= DISPATCH_LEVEL

See also

IoAllocateDriverObjectExtension