You can also use void as a referent type to declare a pointer to an unknown type. C# reference; System.Void You cannot use void as the type of a variable. See also. If a function is defined as “ void ” it does not need to return a value. A void pointer in C is a pointer that does not have any associated data type. One should stop using the ‘void main’ if doing so. Void (NonValue-Returning) functions: Void functions are created and used just like value-returning functions except they do not return a value after the function executes. Well, let us start with C. The official "bible" of C, "The C Programming Language, 2nd edition" by Kernighan and Ritchie states in section A.6.8: Any pointer to an object may be converted to type void* without loss of information. Since we haven’t covered what a pointer is … For more information, see Pointer types. while creating methods we mention whether a method has to return something after executing the block of code enclosed in it or not (Void). Home » C » Pointer » Void Functions in C. ... ("You need a compiler for learning C language.\n"); } The first line in the above definition may also be written as. void Write () Program presents an example where a void function is defined to display a message. In lieu of a data type, void functions use the keyword "void." A void pointer in C clearly indicates that it is empty and can only capable of holding the addresses of any type. One should stop using the ‘void … Declaration. Definition of C Void Pointer. The void keyword has a third (more advanced) use in C++ that we cover in section 9.20 -- Void pointers. The first is a function that prints information for the user to read. Void functions are mostly used in two classes of functions. Void means nothing. Further, these void pointers with addresses can be typecast into any other type easily. Following is the declaration for memchr() function. Functions 2: Void (NonValue-Returning) Functions. Using the return statement in void functions Note that in the example above we didn’t need to use the return statement in the main function. Such functions return control automatically when they reach the end of their body. You will learn more about return values later in this chapter You will learn more about return values later in this chapter Note: In C#, it is good practice to start with an uppercase letter when naming methods, as it makes the code easier to read. void means that this method does not have a return value. The C library function void *memchr(const void *str, int c, size_t n) searches for the first occurrence of the character c (an unsigned char) in the first n bytes of the string pointed to, by the argument str. void main – The ANSI standard says "no" to the ‘void main’ and thus using it can be considered wrong. The reason for this is simple: malloc returns void* and not int*.While in C it's legal to assign void* to int* without a cast, in C++ it isn't.. 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