RtlQueryRegistryValues - NtDoc

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

NTSYSAPI
NTSTATUS
NTAPI
RtlQueryRegistryValues(
    _In_ ULONG RelativeTo,
    _In_ PCWSTR Path,
    _Inout_ _At_(*(*QueryTable).EntryContext, _Pre_unknown_) PRTL_QUERY_REGISTRY_TABLE QueryTable,
    _In_opt_ PVOID Context,
    _In_opt_ PVOID Environment
    );

#endif

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This function is documented in Windows Driver Kit.