Wird...

[Chris]

I encounter this in my current development and hope someone can explain more abt it

Below is a structure that i define in my application. By reference to the MSDN and I get 67 Bytes with reference to the individual data type. But once, i use the sizeof() function, i get 72 bytes. Where the extra 5 bytes come from?

So, in future, should i use the sizeof function? or

typedef struct tagGPS
{
    double TOW;                    // 8 bytes
    double Lat;                    // 8 bytes
    double Lon;                    // 8 bytes
    int Alt;                    // 4 bytes
    int Speed;                    // 4 bytes
    int ClimbRate;                // 4 bytes
    int WeekNum;                // 4 bytes
    double Direction;            // 8 bytes
    int Mode;                    // 4 bytes
    int DOP;                    // 4 bytes
    int NumSat;                    // 4 bytes
    unsigned char Event;        // 1 bytes
    unsigned short MTUid;        // 2 bytes
    unsigned short GPIO;        // 2 bytes
    unsigned short UnitStatus;    // 2 bytes
                                //========
                                //67 bytes 
}GPS; 

[kedaman]

MTUid is aligned after a 3 bytes gap, 2 extra bytes are wasted after UnitStatus, move Event downmost and see if it helps

[Chris]

CornedBee, now I know where the extra 5 bytes come from

Thx a lot.

regards,
Chris.C