#ifndef _NTREGAPI_H

/**
 * Opens an existing registry key.
 * 
 * @param[out] KeyHandle A pointer to a handle that receives the key handle.
 * @param[in] DesiredAccess The access mask that specifies the desired access rights.
 * @param[in] ObjectAttributes A pointer to an OBJECT_ATTRIBUTES structure that specifies the object attributes.
 * @return NTSTATUS Successful or errant status.
 * @remarks NtOpenKey ignores the security information in the ObjectAttributes structure.
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtOpenKey(
    _Out_ PHANDLE KeyHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_ POBJECT_ATTRIBUTES ObjectAttributes
    );

#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwOpenKey(
    _Out_ PHANDLE KeyHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_ POBJECT_ATTRIBUTES ObjectAttributes
    );

#endif
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