When we pass-by-value we are passing a copy of the variable to a function. C can pass a pointer into a function but that is still pass-by-value. It is copying the value of the pointer, the address, into the function. In C++ a reference is an alias for another variable.


What is a file pointer? Introduction. File Pointer: A file pointer is a pointer to a structure, which contains information about the file, including its name, current position of the file, whether the file is being read or written, and whether errors or end of the file have occurred.

what is a pass by value in C++?

The call by value method of passing arguments to a function copies the actual value of an argument into the formal parameter of the function. By default, C++ uses call by value to pass arguments. In general, this means that code within a function cannot alter the arguments used to call the function.

What is overloading in C++? C++ Function Overloading Function Overloading is defined as the process of having two or more function with the same name, but different in parameters is known as function overloading in C++. It is only through these differences compiler can differentiate between the functions.

What is call pointer? The call by pointer method of passing arguments to a function copies the address of an argument into the formal parameter. Inside the function, the address is used to access the actual argument used in the call. To pass the value by pointer, argument pointers are passed to the functions just like any other value.

What are the parameters? In math, a parameter is something in an equation that is passed on in an equation. It means something different in statistics. It's a value that tells you something about a population and is the opposite from a statistic, which tells you something about a small part of the population.

How does pass by value work? By definition, pass by value means you are making a copy in memory of the actual parameter's value that is passed in, a copy of the contents of the actual parameter. Use pass by value when when you are only "using" the parameter for some computation, not changing it for the client program.

What is reference variable?

A reference variable is an alias, that is, another name for an already existing variable. Once a reference is initialized with a variable, either the variable name or the reference name may be used to refer to the variable.

What is pass result?

Pass by Result : This method uses out-mode semantics. Just before control is transfered back to the caller, the value of the formal parameter is transmitted back to the actual parameter. T his method is sometimes called call by result. In general, pass by result technique is implemented by copy.

What is call reference?

The call by reference method of passing arguments to a function copies the reference of an argument into the formal parameter. Inside the function, the reference is used to access the actual argument used in the call. This means that changes made to the parameter affect the passed argument.

What is a pointer in C?

Pointers in C language is a variable that stores/points the address of another variable. A Pointer in C is used to allocate memory dynamically i.e. at run time. The pointer variable might be belonging to any of the data type such as int, float, char, double, short etc.

What is int&?

The value is converted to an int via truncation. In your case "(int&)" was a reinterpret cast. The result is an lvalue that refers to the memory location of b but is treated as an int. It's actually a violation of the strict aliasing rules.

What is a reference in programming?

In computer science, a reference is a value that enables a program to indirectly access a particular datum, such as a variable's value or a record, in the computer's memory or in some other storage device. The reference is said to refer to the datum, and accessing the datum is called dereferencing the reference.

What is a pass by reference in C++?

Pass by reference (C++ only) Pass-by-reference means to pass the reference of an argument in the calling function to the corresponding formal parameter of the called function. The called function can modify the value of the argument by using its reference passed in. The formal parameter is an alias for the argument.

What is this pointer in C++?

C++ this Pointer. Every object in C++ has access to its own address through an important pointer called this pointer. The this pointer is an implicit parameter to all member functions. Therefore, inside a member function, this may be used to refer to the invoking object.

What is reference in C++ with example?

Reference Variables. C++ added the so-called reference variables (or references in short). A reference is an alias, or an alternate name to an existing variable. For example, suppose you make peter a reference (alias) to paul , you can refer to the person as either peter or paul .