结构体 字节对齐的练习

分析结构体大小

struct S1                                                         {                                                                         char c1;                                                                  double d;         char c2;         char c3;                                                 }; struct S2                                                         {                                                                         char c1;                 char c2;         char c3;                                                          double d;                                                          };                 struct S3                                 {                         char c1;                          S1 s;          char c2;         char c3; };        

分析结构体大小

#pragma pack(1) struct S1                                                         {                                                                         char c1;                                                                  double d;         char c2;         char c3;                                                 }; #pragma pack()  struct S3                                 {                         char c1;                          S1 s;          char c2;         char c3; };

分析结构体大小

#pragma pack(4) struct S1                                                         {                                                                         char c1;                                                                  double d;         char c2;         char c3;                                                 }; #pragma pack()  struct S3                                 {                         char c1;                          S1 s;          char c2;         char c3; };

分析结构体大小

struct S1                                                         {                                                                         char c1;                                                                  double d;         char c2;         char c3;                                                 };  #pragma pack(1) struct S3                                 {                         char c1;                          S1 s;          char c2;         char c3; }; #pragma pack()