NtSetTimerEx - NtDoc

#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_WIN7)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtSetTimerEx(
    _In_ HANDLE TimerHandle,
    _In_ TIMER_SET_INFORMATION_CLASS TimerSetInformationClass,
    _Inout_updates_bytes_opt_(TimerSetInformationLength) PVOID TimerSetInformation,
    _In_ ULONG TimerSetInformationLength
    );

#endif
#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwSetTimerEx(
    _In_ HANDLE TimerHandle,
    _In_ TIMER_SET_INFORMATION_CLASS TimerSetInformationClass,
    _Inout_updates_bytes_opt_(TimerSetInformationLength) PVOID TimerSetInformation,
    _In_ ULONG TimerSetInformationLength
    );

#endif
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