site design / logo © 2020 Stack Exchange Inc; user contributions licensed under

It only takes a minute to sign up.I have heard that it is a good practice to write functions that do not receive anything as a parameter like this:But I hear that the right way to express that is like this:What is the difference between these two function declarations in both C and C++?As far as C is concerned, you should never use an empty identifier list in a function declaration In the case of C++, an empty parameter list in either a declaration or a definition indicates that the function takes no arguments, and is equivalent to using a parameter list of In C++, these function declarations are equivalent. This is a duplicate of a thousand other questions on the site network, among others @LarsViklund it is only a duplicate if there is a question on this site. The void function accomplishes its task and then returns control to the caller. Parameters and Arguments. A void function uses a heading that names the function followed by a pair of parentheses. In C++, we must explicitly typecast return value of malloc to (int *). These parameters are used to send back a value (output), or both to send in and out values (input and output) from functions.

You can do this by declaring the parameter to by of type void *, and then casting the appropriate type in the function body, i.e.



I don't think I've ever seen a program that used explicit parameter-lists for forward-declarations of non-variadic functions and @KeithThompson: This question, and this answer, are talking about predeclarations, not function definitions.

Learn more about hiring developers or posting ads with us

Another Example. ... You can add as many parameters as you want, just separate them with a comma: Syntax. Detailed answers to any questions you might have That means the compiler can actually tell you you've made a mistake if you try to pass something. C# reference; System.Void… Stack Exchange network consists of 177 Q&A communities including Parameters and Arguments. By using our site, you acknowledge that you have read and understand our Software Engineering Stack Exchange is a question and answer site for professionals, academics, and students working within the systems development life cycle. Parameters act as variables inside the function. C++ can take the empty parentheses, but C requires the word "void" in this usage. Eventually, it must be cast to another pointer before it is dereferenced. By clicking “Post Your Answer”, you agree to our To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Some Interesting Facts: 1) void pointers cannot be dereferenced.

Information can be passed to functions as a parameter. You cannot use void as the type of a variable. : void (*f)(int). Parameters act as variables inside the method. Anybody can ask a question You can also use void as a referent type to declare a pointer to an unknown type. The void can also appear in the parameter list part of the code to indicate the function takes no actual parameters. The name is preceded by the word "void," which is the type.The void can also appear in the parameter list part of the code to indicate the function takes no actual parameters. I cannot find one, so regardless of what is on SO, this is not a duplicate. In C, the code takes the form: The best answers are voted up and rise to the top In C++, these function declarations are equivalent.


ThoughtCo uses cookies to provide you with a great user experience. A void pointer points to objects of any data type.
Note that the above program compiles in C, but doesn’t compile in C++. C++ can take the empty parentheses, but C requires the word "void" in this usage.

For more information, see Pointer types.