Biegral Blog

     sock_addr和sock_addr_in是有区别的，实际上，它们都在系统库的头文件里面，为了方便起见，我把它们请出来，这样才知道它们的异同，看程序：

#include <stdio.h> 
#include <string.h>

struct in_addr {
        union {
                struct { unsigned char s_b1,s_b2,s_b3,s_b4; } S_un_b;
                struct { unsigned short s_w1,s_w2; } S_un_w;
                unsigned long S_addr;
        } S_un;
#define s_addr  S_un.S_addr
                                /* can be used for most tcp & ip code */
#define s_host  S_un.S_un_b.s_b2
                                /* host on imp */
#define s_net   S_un.S_un_b.s_b1
                                /* network */
#define s_imp   S_un.S_un_w.s_w2
                                /* imp */
#define s_impno S_un.S_un_b.s_b4
                                /* imp # */
#define s_lh    S_un.S_un_b.s_b3
                                /* logical host */
};


struct sockaddr_in {
        short   sin_family;
        unsigned short sin_port;
        struct  in_addr sin_addr;
        char    sin_zero[8];
};


struct sockaddr {
        unsigned short sa_family;              /* address family */
        char    sa_data[14];            /* up to 14 bytes of direct address */
};


int main() 
{ 
	struct sockaddr_in A;
	struct sockaddr *pB = (struct sockaddr *)(&A);

	A.sin_family = 0x1234;
	A.sin_port = 0x4321;
	A.sin_addr.S_un.S_addr = 0xaabbccdd;

	memset(A.sin_zero, 0, sizeof(A.sin_zero));
	strncpy(A.sin_zero, "1234567", 8 - 1);

	printf("%0x, %s\n", pB->sa_family, pB->sa_data);

	return 0; 
} 

1234, !C萏华1234567

       多的就不解释了。