NtQuerySystemInformationEx - NtDoc

#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * The NtQuerySystemInformationEx routine queries information about the system.
 *
 * \param SystemInformationClass The type of information to be retrieved.
 * \param InputBuffer Pointer to a caller-allocated input buffer that contains class-specific information.
 * \param InputBufferLength The size of the buffer pointed to by InputBuffer.
 * \param SystemInformation A pointer to a buffer that receives the requested information.
 * \param SystemInformationLength The size of the buffer pointed to by SystemInformation.
 * \param ReturnLength A pointer to a variable that receives the size of the data returned in the buffer.
 * \return NTSTATUS Successful or errant status.
 * \see https://learn.microsoft.com/en-us/windows/win32/sysinfo/zwquerysysteminformation
 */
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
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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
View code on GitHub