RtlCheckBit macro (wdm.h)
The RtlCheckBit routine determines whether a particular bit in a given bitmap variable is clear or set.
C++
BOOLEAN RtlCheckBit(
[in] PRTL_BITMAP BitMapHeader,
[in] ULONG BitPosition
);
[in] BitMapHeader
A pointer to the RTL_BITMAP structure that describes the bitmap. This structure must have been initialized by the RtlInitializeBitMap routine.
[in] BitPosition
Specifies which bit to check. This is a zero-based value indicating the position of the bit to be tested.
RtlCheckBit returns zero if the given bit is clear, or one if the given bit is set.
Callers of RtlCheckBit 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, RtlCheckBit can be called at any IRQL.
| Requirement | Value |
|---|---|
| Minimum supported client | Available starting with Windows 2000. |
| Target Platform | Desktop |
| Header | wdm.h (include Wdm.h, Ntddk.h, Ntifs.h) |
| IRQL | <= APC_LEVEL (see Remarks section) |