Explain union, C/C++ Programming

Assignment Help:

Unions

A union is also like a structure, except that only single variable in the union is stored in the allocated memory at a time. It is a collection of mutually exclusive variables, which means all of its member variables share the similar physical storage and only one variable is explained at a time. The size of the union is equal to the largest member variables. A union is defined as follows :

                union tag

                 {

                                type memvar1;

                                type memvar2;

                                type memvar3;

                                :

                                :

                 };

 

A union variable of this data type can be declared as follows,

Union tag variable_name;

e.g.

                union utag

                 {

                                int num;

                                char ch;

                 };

                union tag filed;

The above union will have two bytes of storage allocated to it. The variable num can be accessed as field.sum and ch is accessed as field.ch. At any time, only one of these two variables,  can be referred to. Any change made to single variable affects another.

 


Related Discussions:- Explain union

Implement mini version of linux ''tar'', I need to implement a mini version...

I need to implement a mini version of linux''s ''tar'' function in C.

#title.Thick line, #questio c++ program for drawing thick line

#questio c++ program for drawing thick line

Difference between echo and print statement, Difference between Echo and pr...

Difference between Echo and print statement. print()and echo() are language constructs in PHP, both are used to output strings. Both statements are of almost same Speed. ech

What is object variable, The definition of an object(variable ): We can...

The definition of an object(variable ): We can explain a variable(set memory to the variable) in the following ways. e.g. double salary; int month; When more than o

Program that will recursively prompt for input from the user, BACKGROUND: F...

BACKGROUND: FILE SYSTEMS  In a computer, a file system (sometimes written filesystem) is the way in which files are named and where they are placed logically for storage and ret

Explain the switch construct, The Switch Construct The switch statement...

The Switch Construct The switch statement is a multi-way decision-making construct that tests an expression matches one of a number of constant values, and branches accordingly

C, algo of stack using two queue

algo of stack using two queue

Vectors, A body which has three forces acting on it is in equilibrium. One ...

A body which has three forces acting on it is in equilibrium. One force is 3N to the North and the other is 4N to the west. What us the magnitude and direction of the third force?

Advanced input - output routines, Although we can handle most I/O routines ...

Although we can handle most I/O routines with getc and putc , there are file versions of fgets, fputs, fprintf and fscanf . The syntax is       fgets(stringname,n,filename);   Th

Define the system oriented data files, Define the System Oriented Data File...

Define the System Oriented Data Files? System-oriented data files are further closely related to the computer's operating system than Stream- oriented data files and they are s

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd