NtLoadKeyEx - NtDoc

#ifndef _NTREGAPI_H

/**
 * Loads a registry key from a file with extended options.
 * 
 * @param[in] TargetKey A pointer to an OBJECT_ATTRIBUTES structure that specifies the target key.
 * @param[in] SourceFile A pointer to an OBJECT_ATTRIBUTES structure that specifies the source file.
 * @param[in] Flags The options to use when loading the key.
 * @param[in, optional] TrustClassKey A handle to the trust class key.
 * @param[in, optional] Event A handle to an event.
 * @param[in, optional] DesiredAccess The access mask that specifies the desired access rights.
 * @param[out, optional] RootHandle A pointer to a handle that receives the root handle.
 * @param[in, reserved] Reserved Reserved.
 * @return NTSTATUS Successful or errant status.
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtLoadKeyEx(
    _In_ POBJECT_ATTRIBUTES TargetKey,
    _In_ POBJECT_ATTRIBUTES SourceFile,
    _In_ ULONG Flags,
    _In_opt_ HANDLE TrustClassKey,
    _In_opt_ HANDLE Event,
    _In_opt_ ACCESS_MASK DesiredAccess,
    _Out_opt_ PHANDLE RootHandle,
    _Reserved_ PVOID Reserved // previously PIO_STATUS_BLOCK
    );

#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwLoadKeyEx(
    _In_ POBJECT_ATTRIBUTES TargetKey,
    _In_ POBJECT_ATTRIBUTES SourceFile,
    _In_ ULONG Flags,
    _In_opt_ HANDLE TrustClassKey,
    _In_opt_ HANDLE Event,
    _In_opt_ ACCESS_MASK DesiredAccess,
    _Out_opt_ PHANDLE RootHandle,
    _Reserved_ PVOID Reserved // previously PIO_STATUS_BLOCK
    );

#endif
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