Thread: Union in a struct?

Ok, I'm learning Winsock, but there's this part I'm confused about, with a union in a struct (I know how it works but I don't know why it's done like that). This is what it looks like:

Code:

struct in_addr
{
        union
        {
                struct { u_char s_b1,s_b2,s_b3,s_b4; } S_un_b;
                struct { u_short s_w1,s_w2; } S_un_w;
                u_long S_addr;
        } S_un;
};

And the only member of in_addr is the union S_un. What would the point of this be? Wouldn't it be easier and simpler just to use the union without embedding it in a struct?

In a word: compatiblity. This is basicly just the Windows implementation of BSD sockets.

Like so:

Code:

struct in_addr {
   u_long s_addr;
};

Quzah.

Hmm, then in this case, what would the point of having the u_long in the struct be?? Wouldn't it be more practical just to use a u_long variable instead?