PORT_MESSAGE64 - NtDoc

#ifndef _NTLPCAPI_H

// WOW64 definitions

// Except in a small number of special cases, WOW64 programs using the LPC APIs must use the 64-bit versions of the
// PORT_MESSAGE, PORT_VIEW and REMOTE_PORT_VIEW data structures. Note that we take a different approach than the
// official NT headers, which produce 64-bit versions in a 32-bit environment when USE_LPC6432 is defined.

typedef struct _PORT_MESSAGE64
{
    union
    {
        struct
        {
            CSHORT DataLength;
            CSHORT TotalLength;
        } s1;
        ULONG Length;
    } u1;
    union
    {
        struct
        {
            CSHORT Type;
            CSHORT DataInfoOffset;
        } s2;
        ULONG ZeroInit;
    } u2;
    union
    {
        CLIENT_ID64 ClientId;
        double DoNotUseThisField;
    };
    ULONG MessageId;
    union
    {
        ULONGLONG ClientViewSize; // only valid for LPC_CONNECTION_REQUEST messages
        ULONG CallbackId; // only valid for LPC_REQUEST messages
    };
} PORT_MESSAGE64, *PPORT_MESSAGE64;

#endif
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