Name 

Description 

Declarations And Definitions 

Each program must have a single external function named main or WinMain marking the entry point of the program. Functions are usually declared as prototypes in standard or user-supplied header files, or within program files. Functions are external by default and are normally accessible from any file in the program. You can restrict visibility of functions by using the static storage class specifier (see Linkage).
Functions are defined in your source files or made available by linking precompiled libraries.
A given function can be declared several times in a program, provided the declarations are compatible. Nondefining function declarations using... more 

The main() Function 

 

Declarations And Prototypes 

In the Kernighan and Ritchie style of declaration, a function could be implicitly declared by its appearance in a function call, or explicitly declared as follows
<type> func()
where type is the optional return type defaulting to int. In C++, this declaration means <type> func(void). A function can be declared to return any type except an array or function type. This approach does not allow the compiler to check that the type or number of arguments used in a function call match the declaration.
This problem was eased by the introduction of function prototypes with... more 

Definitions 

The general syntax for external function definitions is as follows:
External function definitions  

Extended Types Formatted I/O 

The following table shows new format specifiers implemented in C++ Builder for the printf and scanf family of functions. This implementation allows the input and output of 64-bit integers and provides greater I/O flexibility for other types.  

Formal Parameter Declarations 

The formal parameter declaration list follows a syntax similar to that of the declarators found in normal identifier declarations. Here are a few examples:  

Function Calls And Argument Conversions 

A function is called with actual arguments placed in the same sequence as their matching formal parameters. The actual arguments are converted as if by initialization to the declared types of the formal parameters.
Here is a summary of the rules governing how the compiler deals with language modifiers and formal parameters in function calls, both with and without prototypes:

• The language modifiers for a function definition must match the modifiers used in the declaration of the function at all calls to the function.
• A function can modify the values of its formal parameters, but this has no effect on... more