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C参考手册

C 语法

File scope

如果声明标识符的声明符或类型说明符出现在任何块或参数列表之外,则标识符具有文件范围,该范围终止于翻译单元的末尾。

因此,在任何块或参数列表之外放置标识符的声明(在声明符或类型说明符中)意味着该标识符具有文件范围。标识符的文件范围从声明延伸到声明出现的翻译单元的末尾。

标识符 a,b,f 和 g 具有文件范围。

#include <stdio.h>
 
int a = 1;
static int b = 2;
 
void f (void) {printf("from function f()\n");}
static void g (void) {printf("from function g()\n");}
 
int main(void)
{
    f();
    g();
 
    return 0;
}
/* end of this translation unit, end of file scope */

可能的输出:

from function f()
from function g()

C 语法相关

1.#define directive
2.#elif directive
3.#else directive
4.#endif directive
5.#error directive
6.#if directive
7.#ifdef directive
8.#ifndef directive
9.#include directive
10.#line directive
11.#pragma directive
12.alignas
13.Alternative operators and tokens
14.Analyzability
15.Arithmetic operators
16.Arithmetic types
17.Array declaration
18.Array initialization
19.ASCII Chart
20.Assignment operators
21. types
22.Basic concepts
23.Bit fields
24.break statement
25.C language
26.C Operator Precedence
27.cast operator
28.character constant
29.Comments
30.Comparison operators
31.compound literals
32.Conditional inclusion
33.Conformance
34.const type qualifier
35.Constant expressions
36.continue statement
37.Declarations
38.do-while loop
39.Enumerations
40.Escape sequences
41.Expressions
42.External and tentative definitions
43.floating constant
44.for loop
45.Function declarations
46.Function definitions
47.Functions
48.Generic selection
49.goto statement
50.Identifier
51.if statement
52.Implicit conversions
53.Increment/decrement operators
54.Initialization
55.inline function specifier
56.integer constant
57.Lifetime
58.Logical operators
59.Lookup and name spaces
60.Main function
61.Member access operators
62.Memory model
63.Objects and alignment
64.Order of evaluation
65.Other operators
66.Phases of translation
67.Pointer declaration
68.Preprocessor
69.restrict type qualifier
70.return statement
71.Scalar initialization
72.Scope
73.sizeof operator
74.Statements
75.static assert declaration
76.Static storage duration
77.Storage-class specifiers
78.string literals
79.Struct and union initialization
80.Struct declaration
81.switch statement
82.Thread storage duration
83.Type
84.Type
85.Typedef declaration
86.Undefined behavior
87.Union declaration
88.Value categories
89.Variadic arguments
90.volatile type qualifier
91.while loop
92._Alignof operator
93._Noreturn function specifier
C

C 语言是一门通用计算机编程语言,应用广泛。C 语言的设计目标是提供一种能以简易的方式编译、处理低级存储器、产生少量的机器码以及不需要任何运行环境支持便能运行的编程语言。