Every function declaration and definition
must specify a return type, whether or not it actually returns a value.The result of a function is called its return value and the data type of the return value is called the return type.
Every function declaration and definition
must specify a return type, whether or not it actually returns a value.
If a function declaration does not specify
a return type, the compiler assumes an implicit return type of int.
However, for conformance to C99, you should specify a return type
for every function declaration and definition, whether or not the
function returns int.
A function may be defined to return any type of value, except an array type or a function type; these exclusions must be handled by returning a pointer to the array or function. When a function does not return a value, void is the type specifier in the function declaration and definition.
A function cannot be declared as returning a data object having a volatile or const type, but it can return a pointer to a volatile or const object.
A function can have a return type that is a user-defined type. For example:
enum count {one, two, three};
enum count counter();
The user-defined type may also be defined
within the function declaration.
The
user-defined type may not be defined within the function declaration.
enum count{one, two, three} counter(); // legal in C
enum count{one, two, three} counter(); // error in C++
References can also be used as return
types for functions. The reference returns the lvalue of the object
to which it refers.
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