yes
Your question makes no sense.
storage_class return_type name parameter-list
example: size_t strlen (const char *s);
A prototype in C is the declaration of a function. Without a prototype, the function cannot be called because the compiler would have no way of knowing if the function was being called correctly. Prototypes may appear in multiple translation units but can only be defined once. A definition is itself a prototype.
Yes. Examples can be found in stdio.h
In C, a function prototype is a declaration to the compiler that a certain function exists, without a full definition. This allows other functions to call that function. The linker will later make sure that a function definition actually exists (perhaps somewhere else), and will turn the call to the function to a call to the correct function.
'Clearscreen' is not used in C language. TurboC has a clrscr function (prototype in conio.h).
No, because there are no objects in C.
A reference variable in C++ is a formal parameter of a function call that automatically dereferences itself, as if it were a pointer, into a reference to the original value in the calling routine. You declare the reference type in the function declaration and prototype, but the compiler automatically adds the reference (&) operator on call, and the dereference (*) operator on use.
list of header files in c and function prototype associated with each file
yes, we can not declare a function in the body of another function. but if we declare a function in the body of another function then we can call that very function only in that particular function in which it is declared; and that declared function is not known to other functions present in your programme. So if a function is required in almost all functions of your programme so you must declare it outside the main function i.e in the beginning of your programme.
Prototyping is done (at least in C/C++) to declare a function and tell the compiler how to use it before the int main(void) part of the program is run. The function is declared after main and is usually done as a style thing. example int function(int); int main(void) { int anumber = 1; x = function(anumber); return 0; } int function(int number) { //do something return number; } et cetera et cetera...