extern

I've got a C# extern declaration that goes like this: [DllImport("something.dll")] public static extern ReturnCode GetParent(IntPtr inRef, out IntPtr outParentRef); How to translate that to F#? You can try something like the code below. I don't know what ReturnCode is, so the code below expects it is an integer. For any more complex type, you'll need to use [<Struct>] attribute as in the answer referenced by A-Dubb. type ReturnCode = int [<System.Runtime.InteropServices.DllImport("something.dll")>] extern ReturnCode GetParent(System.IntPtr inRef, System.IntPtr& outParentRef); To call the

I have gone through following two questions: static and extern global variables in C and C++ global variable in C are static or not? Both questions says the two things in different way. Question 1's Answer: Global variables are not extern nor static by default on C and C++. Question 2's Answer: If you do not specify a storage class (that is, the extern or static keywords), then by default global variables have external linkage I need to know the following: Are global variables extern by default in linkage (or) is it equivalent to declaring variables by specifying extern storage class? Are

转载https://www.cnblogs.com/GavinDai/archive/2011/10/24/2222735.html 变量声明和定义的区别 我们在程序设计中，时时刻刻都用到变量的定义和变量的声明，可有些时候我们对这个概念不是很清楚，知道它是怎么用，但却不知是怎么一会事，下面我就简单的把他们的区别介绍如下：(望我的指点对你受益) 变量的声明有两种情况： 1、一种是需要建立存储空间的。例如：int a 在声明的时候就已经建立了存储空间。 2、另一种是不需要建立存储空间的。 例如：extern int a 其中变量a是在别的文件中定义的。 前者是“定义性声明（defining declaration）”或者称为“定义（definition）”，而后者是“引用性声明（referncing declaration）”，从广义的角度来讲声明中包含着定义，即定义是声明的一个特例，所以并非所有的声明都是定义，例如：int a 它既是声明，同时又是定义。然而对于 extern a 来讲它只是声明不是定义。一般的情况下我们常常这样叙述，把建立空间的声明称之为“定义”，而把不需要建立存储空间的声明称之为“声明”。很明显我们在这里指的声明是范围比较窄的，即狭义上的声明，也就是说非定义性质的声明，例如：在主函数中： int main() { extern int A; /

Just want to confirm in Windows environment, VSTS 2008 + C++ project, we could only apply extern C to function level, not be able to apply to class level (so that all member functions from the class use C language name mangling)? I have tried several ways, but always compile error. thanks in advance, George You can sort of apply extern "C" to a member function via a very convoluted (but entirely legal) hack: extern "C" typedef int bar_t(int x); struct foo { bar_t bar; // yes, this declares a nonstatic member function! }; int foo::bar(int x) { return x; } // definition This is possible

What is default storage class of a global variable? While searching on web I found, some sites say it is static . But, static means internal linkage and the variable can not be available outside the file scope i.e it should not be available to other object files. But, they still can be accessed to other files using declarations like extern int i . And, if I explicitly mention static to global variable then it is not available outside the file scope. Then, what is correct default storage class for the global variables? The default storage duration is static, but default linkage is external. You