NtQuerySystemInformationEx - NtDoc

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

NTSYSCALLAPI
NTSTATUS
NTAPI
NtQuerySystemInformationEx(
    _In_ SYSTEM_INFORMATION_CLASS SystemInformationClass,
    _In_reads_bytes_(InputBufferLength) PVOID InputBuffer,
    _In_ ULONG InputBufferLength,
    _Out_writes_bytes_opt_(SystemInformationLength) PVOID SystemInformation,
    _In_ ULONG SystemInformationLength,
    _Out_opt_ PULONG ReturnLength
    );

#endif
#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwQuerySystemInformationEx(
    _In_ SYSTEM_INFORMATION_CLASS SystemInformationClass,
    _In_reads_bytes_(InputBufferLength) PVOID InputBuffer,
    _In_ ULONG InputBufferLength,
    _Out_writes_bytes_opt_(SystemInformationLength) PVOID SystemInformation,
    _In_ ULONG SystemInformationLength,
    _Out_opt_ PULONG ReturnLength
    );

#endif
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