SOCKET 常用数据类型分析

from http://blog.csdn.net/icedmilk/article/details/5336188

1. SOCKET (套接字)

 

typedef    UINT_PTR        SOCKET;
typedef    unsigned int    UINT_PTR;

 

4个字节

 

2. sockaddr, SOCKADDR, PSOCKADDR (网络地址,通用)

typedef    sockaddr    SOCKADDR, *PSOCKADDR;

 

struct sockaddr {

    unsigned short    sa_family;
    char              sa_data[14];

};

 

16个字节，并不直接使用，sa_data成员会被细化

 

3. sockaddr_in, SOCKADDR_IN, PSOCKADDR_IN (网络地址,internet style)

 

typedef    struct sockaddr_in    SOCKADDR_IN, *PSOCKADDR_IN;

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

 

16个字节,sockaddr_in是sockaddr的细化

 

4. in_addr (网络IP)

 

typedef    struct in_addr    IN_ADDR, *PIN_ADDR;

 

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;
}

4字节,4个字节采用的是网络字节序