void

I saw some usage of (void*) in printf() . If I want to print a variable's address, can I do it like this: int a = 19; printf("%d", &a); I think, &a is a 's address which is just an integer, right? Many articles I read use something like this: printf("%p", (void*)&a); What does %p stand for? (A pointer?) Why use (void*) ? Can't I use (int)&a instead? Pointers are not numbers. They are often internally represented that way, but they are conceptually distinct. void* is designed to be a generic pointer type. Any pointer value (other than a function pointer) may be converted to void* and back again

Which is more correct way to return from function: void function() { // blah some code } OR void function() { // blah some code return; } Rationale for second way: It expresses developer intentions more clearly. It helps detecting function end at pre-compile time: Suppose you have such scenario- you have bunch of functions and you must inject some code at the end of those functions. But for some reasons you don't want / or can't modify such huge amount of functions. What can you do about that ? Return & macro comes into play, for example: #include<stdio.h> #define MAX_LINES 1000 #define XCAT(a

Ok, so I have heard different opinions on this subject and just want to make sure I understand it correctly. For C++ Declarations void f(); and void f(void); mean precisely the same thing, the function f does not take any parameters. Ditto for definitions. For C Declaration void f(void); means that f does not take any parameters. Declaration void f(); means that function f may or may not have parameters, and if it does, we don't know what kind of parameters those are, or how many there is of them. Note that it is NOT the same as ellipsis, we can't use va_list . Now here is where things get

I do not understand why this code compiles without error: #include <iostream> template <class T> struct Test { static constexpr T f() {return T();} }; int main() { Test<void> test; test.f(); // Why not an error? return 0; } Is it ok according to the standard, or is it a compiler tolerance? Shafik Yaghmour This looks valid by the draft C++11 standard , if we look at section 5.2.3 Explicit type conversion (functional notation) paragraph 2 says ( emphasis mine ): The expression T() , where T is a simple-type-specifier or typename-specifier for a non-array complete object type or the (possibly cv

I know that methods declared with void does not return anything. But it seems that in C# void is more then just a keyword, but a real type. void is an alias for System.Void like int that is for System.Int32 . Why am I not allowed to use that type? It does not make any sense, but this are just some thoughts about the logic. Neither var nothing = new System.Void(); (which says i should use void (Not an alias?)) nor var nothing = new void(); compiles. It is also not possible to use something like that: void GiveMeNothing() { } void GiveMeNothingAgain() { return GiveMeNothing(); } So whats the