NtAlpcQueryInformationMessage - NtDoc

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

NTSYSCALLAPI
NTSTATUS
NTAPI
NtAlpcQueryInformationMessage(
    _In_ HANDLE PortHandle,
    _In_ PPORT_MESSAGE PortMessage,
    _In_ ALPC_MESSAGE_INFORMATION_CLASS MessageInformationClass,
    _Out_writes_bytes_to_opt_(Length, *ReturnLength) PVOID MessageInformation,
    _In_ ULONG Length,
    _Out_opt_ PULONG ReturnLength
    );

#endif
// end_private
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwAlpcQueryInformationMessage(
    _In_ HANDLE PortHandle,
    _In_ PPORT_MESSAGE PortMessage,
    _In_ ALPC_MESSAGE_INFORMATION_CLASS MessageInformationClass,
    _Out_writes_bytes_to_opt_(Length, *ReturnLength) PVOID MessageInformation,
    _In_ ULONG Length,
    _Out_opt_ PULONG ReturnLength
    );

#endif
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