功能和返回为const char * [英] Functions and return const char*

问题描述

const char* test(bool i)
{
    const char t[] = "aa\n";
    const char* p = "bbb\n";
    if(i)
        return p;
    return t;
}
int main(array<System::String ^> ^args)
{
     printf(test(true));
     printf(test(false));
     return 0;
}

这将返回诸如此类的东西：

That returns something of sort:

 bbb
 %^&$^$%

很显然，测试（假）返回一个指向一个局部变量。的问题是，p是也局部变量。为什么BBB \\ n时，存储在函数返回后不清洗。我想为const char []是国际preTED同样的方式为const char *，但是，因为它似乎是不正确的。

It is clear that test(false) returns a pointer to a local variable. The question is that p is also local variable. Why the memory for "bbb\n" is not cleaned after the function returns. I thought const char[] is interpreted same way as const char* but it is not true as it seems.

推荐答案

P 是一个局部变量，您可以通过值返回，而是指向了一个字符串文字，它驻留在只读存储器，而不是分配给方法自动记忆。

p is a local variable, which you return by value, but points to a string literal, which resides in read-only memory, not in the automatic memory allocated for the method.

返回 T 和使用它确实导致不确定的行为。

Returning t and the using it indeed results in undefined behavior.

另外，不要以为指针和数组的是相同的。

Also, don't think of pointers and arrays to be equivalent.

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