RtlNumberOfClearBits - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers 
#ifndef _NTRTL_H

NTSYSAPI
ULONG
NTAPI
RtlNumberOfClearBits(
    _In_ PRTL_BITMAP BitMapHeader
    );

#endif

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// wdm.h

NTSYSAPI ULONG RtlNumberOfClearBits(
  [in] PRTL_BITMAP BitMapHeader
);
View the official Windows Driver Kit DDI reference

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This function is documented in Windows Driver Kit.

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Windows Driver Kit DDI reference (nf-wdm-rtlnumberofclearbits)

RtlNumberOfClearBits function

Description

The RtlNumberOfClearBits routine returns a count of the clear bits in a given bitmap variable.

Parameters

BitMapHeader [in]

A pointer to the RTL_BITMAP structure that describes the bitmap. This structure must have been initialized by the RtlInitializeBitMap routine.

Return value

RtlNumberOfClearBits returns the number of bits that are currently clear.

Remarks

Callers of RtlNumberOfClearBits must be running at IRQL <= APC_LEVEL if the memory that contains the bitmap variable is pageable or the memory at BitMapHeader is pageable. Otherwise, RtlNumberOfClearBits can be called at any IRQL.

See also

RTL_BITMAP

RtlFindClearBits

RtlFindClearRuns

RtlFindFirstRunClear

RtlFindLastBackwardRunClear

RtlFindLongestRunClear

RtlFindNextForwardRunClear

RtlInitializeBitMap

RtlNumberOfSetBits

View the official Windows Driver Kit DDI reference

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