PORT_MESSAGE - NtDoc

#ifndef _NTLPCAPI_H

typedef struct _PORT_MESSAGE
{
    union
    {
        struct
        {
            CSHORT DataLength;
            CSHORT TotalLength;
        } s1;
        ULONG Length;
    } u1;
    union
    {
        struct
        {
            CSHORT Type;
            CSHORT DataInfoOffset;
        } s2;
        ULONG ZeroInit;
    } u2;
    union
    {
        CLIENT_ID ClientId;
        double DoNotUseThisField;
    };
    ULONG MessageId;
    union
    {
        SIZE_T ClientViewSize; // only valid for LPC_CONNECTION_REQUEST messages
        ULONG CallbackId; // only valid for LPC_REQUEST messages
    };
} PORT_MESSAGE, *PPORT_MESSAGE;

#endif
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