static 可能是C和C ++中最令人困惑的重载关键字.在不同的地方意味着不同的事情.

static is probably the most confusingly overloaded keyword in both C and C++. It means different things in different places.

• 在函数中， static 是一个存储类，表示在程序生命周期内存在的变量.这么说

• Within functions, static is a storage class, denoting variables which exist for the lifetime of the programme. So saying

void f() {
    static int i = 0;
}

表示 i 的值将在对 f()的调用之间保留.其他存储类是默认的 auto (但要注意C ++ 11中含义的更改)， extern 和 register ，以及 thread_local .

says that the value of i will be preserved between calls to f(). Other storage classes are the default auto (but beware the change in meaning in C++11), extern, and register, plus thread_local in C11/C++11.

在文件范围(或C ++中的命名空间范围)， static 是链接说明符.以这种方式标记为 static 的函数和变量具有内部链接，因此对于当前翻译单元而言是本地的.这意味着像

At file scope (or namespace scope in C++), static is a linkage specifier. Functions and variables marked static in this way have internal linkage, and so are local to the current translation unit. What this means is that a function like

 static int f() {
     return 3;
 }

只能由同一 .c 文件中的其他函数引用.在C ++ 03中，不推荐使用 static ，而使用未命名的名称空间.我读过某个地方，它在C ++ 11中再次被弃用.

can only be referenced by other functions inside the same .c file. This usage of static was deprecated in C++03 in favour of unnamed namespaces. I read somewhere it was undeprecated again in C++11.

在C ++中，当应用于类的成员函数或成员变量时，这意味着该函数或变量不需要类实例即可被访问.在实现方面，类静态"成员函数/变量与全局函数/变量之间几乎没有什么区别，只是C ++类访问说明符适用于成员.

In C++, when applied to a member function or member variable of a class, it means that the function or variable does not need a class instance in order to be accessed. There is little different between "class static" member functions/variables and global functions/variable in terms of implementation, except that C++ class access specifiers apply to members.

最后一个:在C99(但不是C ++)中， static 可以在数组函数参数中使用，如下所示:

One last one: in C99 (but not C++), static can be used within an array function parameter, like so:

void f(int a[static 4]) {
}

这指定参数 a 必须是大小至少为4的整数数组.

this specifies that the parameter a must by an integer array of size at least 4.

我想这些都是全部，但是如果您有遗忘的地方，请在评论中告诉我！

I think that's all of them, but let me know in the comments if there are any I've forgotten!