_PORT_MESSAGE

Metadatacopy
struct _PORT_MESSAGE {
    union {
        struct {
            short DataLength;/* 0x0  2 */
            short TotalLength;/* 0x2  2 */
        } s1;/* 0x0  4 */
        unsigned long Length;/* 0x0  4 */
    } u1;/* 0x0  4 */
    union {
        struct {
            short Type;/* 0x4  2 */
            short DataInfoOffset;/* 0x6  2 */
        } s2;/* 0x4  4 */
        unsigned long ZeroInit;/* 0x4  4 */
    } u2;/* 0x4  4 */
    union {
        struct _CLIENT_ID ClientId;/* 0x8  8 */
        double DoNotUseThisField;/* 0x8  8 */
    };/* 0x8  8 */
    unsigned long MessageId;/* 0x10  4 */
    union {
        unsigned long ClientViewSize;/* 0x14  4 */
        unsigned long CallbackId;/* 0x14  4 */
    };/* 0x14  4 */
};
/* source: Windows 2000 RC2 DDK Alpha libcntpr.lib CodeView type records; build 2128 per the DDK's ntverp.h */