What does x- mean in C language?

"x->" in C language is the arrow operator, used to access structure or union members pointed to by pointers. It is mainly used in the following situations: accessing structures or unions through pointers Body members When you need to avoid compiler warnings when a structure or union is defined as a typedef

"x->" in C language is What's the meaning?

"x->" in C language is the arrow operator, used to access structure or union members. It is similar to the dot operator ("."), but has the following key differences:

1. Structure pointer:

The dot operator is used to access structures members of a variable, while the arrow operator is used to access members of a structure pointed to by a pointer. For example:

<code class="c">struct Person {
  char name[20];
  int age;
};

Person p = { "John", 30 };

printf("%s is %d years old.\n", p.name, p.age);</code>

<code class="c">struct Person *ptr = &p;

printf("%s is %d years old.\n", ptr->name, ptr->age);</code>

2. Dereferencing:

The arrow operator automatically dereferences the structure pointer, which means it first gets the structure pointed to by the pointer, and then Visit its members. The dot operator assumes that the structure variable already exists and does not need to be dereferenced.

When to use "x->"?

The arrow operator is used in the following situations:

• When accessing structure or union members through pointers.
• When a structure or union is defined as a typedef.
• When you need to avoid compiler warnings (e.g. potentially uninitialized pointers).

Example usage:

<code class="c">// 通过指针访问结构体
struct Student {
  char name[20];
  int marks;
};

Student *s = malloc(sizeof(Student));
strcpy(s->name, "Jane");
s->marks = 90;</code>

<code class="c">// 定义 typedef 结构体
typedef struct {
  char name[20];
  int age;
} Person;

Person *p = malloc(sizeof(Person));
strcpy(p->name, "John");
p->age = 30;</code>

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