#ifndef _NTPOAPI_H

/**
 * The NtInitiatePowerAction routine initiates a shutdown and optional restart of the specified computer.
 *
 * \param SystemAction The system power action.
 * \param LightestSystemState The lightest system power state.
 * \param Flags Flags for the power action.
 * \param Asynchronous Whether the action is asynchronous.
 * \return Successful or errant status.
 * \sa https://learn.microsoft.com/en-us/windows/win32/api/winreg/nf-winreg-initiatesystemshutdownw
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtInitiatePowerAction(
    _In_ POWER_ACTION SystemAction,
    _In_ SYSTEM_POWER_STATE LightestSystemState,
    _In_ ULONG Flags, // POWER_ACTION_* flags
    _In_ BOOLEAN Asynchronous
    );

#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwInitiatePowerAction(
    _In_ POWER_ACTION SystemAction,
    _In_ SYSTEM_POWER_STATE LightestSystemState,
    _In_ ULONG Flags, // POWER_ACTION_* flags
    _In_ BOOLEAN Asynchronous
    );

#endif
View code on GitHub