Functions

• saves repetition of common routines
• modularizes the program, making it easier to use:
• allows recursive processes

return-type function-name(argument definitions)
{
    local variable definitions
    statements
}

Function Declaration ANSI (Prototype)

return-type function-name(argument declarations); 

return-type function-name()
    argument definitions
{
    local variable definitions
    statements
}

Function Declaration K&R (Prototype)

return-type function-name();
    

• A function is an expression of the return type.
• The argument list is a comma separated list of argument expressions.
• Each argument expression is evaluated, copied (pass by value) and then converted to its corresponding argument type when calling the function.