Structure

Structure names form a separate namespace
```
struct STRUCT {
  member1type member1;
  member2type member2;
};
```
usage in declarations and definitions requires keyword struct in C (recommended to C++ too)
```
struct STRUCT s;
```
typedef can be used to shorten declarations and definitions
```
typedef struct STRUCT Struct;
Struct s;
```

typedef and struct declarations can be combined into one construct

typedef struct STRUCT {
  member1type member1;
  member2type member2;
} Struct;

Typically, inner struct declaration needs no name

typedef struct {
  member1type member1;
  member2type member2;
} Struct;

Definition of pointer to structure type

typedef struct STRUCT {
  member1type member1;
  member2type member2;
} *Struct;

// usage in application
Struct s;	// variable of pointer type, not structure type

Pointer to structure is efficient in passing parameters, but definition of pointer to structure type leads many confusion and require manual memory allocation. With the introduction of reference variable, its usage is less popular.

Struct s[STRUCTNUM];
Struct *p = s;
p++;	// point to (s+sizeof s) = s[1]

Index