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问 请问，就是下面的问题
typedef struct
{
   unsigned short  h_type;
   unsigned short  p_type;           
   unsigned char   h_len;
   unsigned char   i_len;               
   unsigned short  m_type;
   unsigned char   sr[6];              
   unsigned int    sddr;
   unsigned char   dr[6];    
   unsigned int    dddr;
} ARP_HEADER;

uchar RXT[] = {
               0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x03,0x0F,
               0xF9,0xAE,0xF9,0x08,0x06,0x00,0x01,0x08,0x00,
               0x06,0x04,0x00,0x01,0x00,0x03,0x0F,0xF9,0xAE,
               0xF9,0xC0,0xA8,0x01,0xFA,0x00,0x00,0x00,0x00,
               0x00,0x01,0xC0,0xA8,0x01,0xFA,0x66
               };


   uint volatile w;
   ARP_HEADER * ar;
      
   arp = (ARP_HEADER *)(RXT + 14);
   w = ar->daddr;    //这个总是不对
   w = ar->sddr;  //这个正确

这样的结构我读dddr的数据总是不对，为什么？  答 1: ALIGN 引起的.#pragma pack(push,1)
typedef struct
{
   unsigned short  h_type;
   unsigned short  p_type;           
   unsigned char   h_len;
   unsigned char   i_len;               
   unsigned short  m_type;
   unsigned char   sr[6];              
   unsigned int    sddr;
   unsigned char   dr[6];    
   unsigned int    dddr;
} ARP_HEADER;
#pragma pack(pop)