Memory layout of classes & structures

[anw]

Back in the old days of ANSI C programming, one could copy the data in one structure to another with code similar to the following:

struct myStruct
{
 int var1;
 char *var2;
};

struct myStruct s1;
struct myStruct s2;

memcpy(s2, s1, sizeof(struct myStruct));

On most machines, this was a lot more efficient than doing a member- by- member assignment.

Can one do this with C++ classes and structures? What about the vtable? Is it stored in the class/ struct?

And, if there is extra "stuff" in the class/ struct that prohibits one from doing this, how does one send and receive data blocks over a TCP/ IP connection, e. g.,

send(sock, myStruct, sizeof(myStruct), 0);

Thanks in advance,
Allen