#ifndef _NTREGAPI_H

/**
 * Queries the value of a registry key.
 * 
 * @param[in] KeyHandle A handle to the key to be queried.
 * @param[in] ValueName A pointer to a UNICODE_STRING structure that specifies the name of the value to be queried.
 * @param[in] KeyValueInformationClass The type of information to be queried.
 * @param[out] KeyValueInformation A pointer to a buffer that receives the value information.
 * @param[in] Length The size of the buffer.
 * @param[out] ResultLength A pointer to a variable that receives the size of the data returned.
 * @return NTSTATUS Successful or errant status.
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtQueryValueKey(
    _In_ HANDLE KeyHandle,
    _In_ PUNICODE_STRING ValueName,
    _In_ KEY_VALUE_INFORMATION_CLASS KeyValueInformationClass,
    _Out_writes_bytes_to_opt_(Length, *ResultLength) PVOID KeyValueInformation,
    _In_ ULONG Length,
    _Out_ PULONG ResultLength
    );

#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwQueryValueKey(
    _In_ HANDLE KeyHandle,
    _In_ PUNICODE_STRING ValueName,
    _In_ KEY_VALUE_INFORMATION_CLASS KeyValueInformationClass,
    _Out_writes_bytes_to_opt_(Length, *ResultLength) PVOID KeyValueInformation,
    _In_ ULONG Length,
    _Out_ PULONG ResultLength
    );

#endif
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