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VideoPortZeroMemory function

The VideoPortZeroMemory function fills a block of system memory with zeros.

Syntax


VOID VideoPortZeroMemory(
  _Out_ PVOID Destination,
        ULONG Length
);

Parameters

Destination [out]

Specifies the starting address of the block of memory. This value must be in a mapped logical range returned by VideoPortGetDeviceBase.

Length

Specifies the size, in bytes, of the block.

Return value

None

Remarks

Miniport drivers' DriverEntry functions generally call VideoPortZeroMemory to initialize the VIDEO_HW_INITIALIZATION_DATA structure with zeros.

The given Destination must be in a mapped logical range returned by VideoPortGetDeviceBase and/or a system space RAM address, such as an address on the stack. Use VideoPortZeroDeviceMemory to fill any device-memory block, such as a frame buffer, with zeros.

A miniport driver's HwVidInterrupt or HwVidSynchronizeExecutionCallback function can call VideoPortZeroMemory.

Callers of VideoPortZeroMemory can be running at any IRQL if the memory pointed to by the Destination parameter is in nonpaged pool. Otherwise, the caller must be running at IRQL < DISPATCH_LEVEL.

Requirements

Target platform

Desktop

Version

Available in Windows 2000 and later versions of the Windows operating systems.

Header

Video.h (include Video.h)

Library

Videoprt.lib

DLL

Videoprt.sys

IRQL

See Remarks section.

See also

DriverEntry
HwVidInterrupt
HwVidSynchronizeExecutionCallback
VIDEO_HW_INITIALIZATION_DATA
VideoPortCompareMemory
VideoPortMoveMemory
VideoPortZeroDeviceMemory

 

 

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