INT main（）和INT主要（无效）之间的区别？ [英] Difference between int main() and int main(void)?

问题描述

什么以下意思是：

int main(void) {...} 

VS

int main() {...}

我觉得 INT的main（）{...} 意味着主不接受任何参数（命令行），但是：

I think that int main() {...} means that main doesn't receive any parameters (from command line) , however:

int main(int argc, char *argv[])

确实

但什么是 INT主要（无效）{...} 意味着什么？什么是的无效表示？

But what does int main(void) {...} means ? what does the void stands for ?

我在这里看着 但它在某种程度上一个不同的问题。

I've looked here but it's somehow a different question .

推荐答案

在C ++中，没有任何区别。

In C++, there is no difference.

在C，所不同​​的是值得商榷的。一些爱争辩，后者版本（一个没有无效）在技术上只是一个常见的​​实现扩展，并且不保证的标准，因为标准措辞的工作。但是，标准中明确规定，在函数定义空集的参数有一个良好定义的行为：该函数不带任何参数。为主要因而这样的定义在标准以下的说明相符：

In C, the difference is questionable. Some love to argue that the latter version (the one without void) is technically just a common implementation extension and not guaranteed to work by the standard because of the wording in the standard. However, the standard clearly states that in a function definition an empty set of parameters has a well-defined behaviour: that the function does not take any parameters. Thus such a definition for main matches the following description in the standard:

据[主]应为int的返回类型和不带参数来定义。

It [main] shall be defined with a return type of int and with no parameters.

有，然而，两者之间有明显的区别：不即版本无效未能提供正确的原型功能：

There is, however, a noticeable difference between the two: namely, the version without void fails to provide a correct prototype for the function:

// this is OK.
int main()
{
  if (0) main(42);
}

// this requires a diagnostic to be shown during compiling
int main(void)
{
  if (0) main(42);
}

哦，只是为了完成：在无效在所有函数声明的含义如下：

Oh, and just to be complete: the void has the following meaning in all function declarators:

（6.7.6.3p10）void类型的未命名参数的特殊情况下，如在列表中的唯一项目指定函数没有参数。

(6.7.6.3p10) The special case of an unnamed parameter of type void as the only item in the list specifies that the function has no parameters.

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