NtAlpcQueryInformation - NtDoc

#ifndef _NTLPCAPI_H
// begin_private
#if (PHNT_VERSION >= PHNT_VISTA)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtAlpcQueryInformation(
    _In_opt_ HANDLE PortHandle,
    _In_ ALPC_PORT_INFORMATION_CLASS PortInformationClass,
    _Inout_updates_bytes_to_(Length, *ReturnLength) PVOID PortInformation,
    _In_ ULONG Length,
    _Out_opt_ PULONG ReturnLength
    );

#endif
// end_private
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwAlpcQueryInformation(
    _In_opt_ HANDLE PortHandle,
    _In_ ALPC_PORT_INFORMATION_CLASS PortInformationClass,
    _Inout_updates_bytes_to_(Length, *ReturnLength) PVOID PortInformation,
    _In_ ULONG Length,
    _Out_opt_ PULONG ReturnLength
    );

#endif
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