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Programming is all about defining variables and using them at specific locations while compiling software.

The storage classes and their properties in C programming are no different. This blog post has been designed to make you understand what is storage class in C programming. 

Well, these classes in C programming are centered around defining the use of the variables and functions at different instances.

You can check the life span, visibility and the scope of these variables using each of the storage classes that are available in C.

From memory to the location, every bit of information is available in the variables and functions that are used for creating programs.

Don't stay neglected on the properties of the storage classes in C and check out this blog to get future references in C programming.


What is the Storage Class in C?

The storage classes in C programming are commonly used for describing the important properties of the functions and variables that are used within programs.

These properties can be of several types such as the lifetime, the visibility or the scope of the classes. 

You can basically track the location of any given function or variable by making use of these properties. But, keep in mind that this process can only be executed while the program is still operational.

So, now that you have your answer to what is storage class in C, have a look at some of the features for the storage classes that you need to know about:

  • You can essentially use any form of storage classes in C programming for depicting any sort of additional information for the variables
  • The storage class basically acts as a guide for the users to locate any variant of their choice within the program
  • Using the storage classes in C programming, you can not only specify the variables but also the parameters for the variables as well
  • You can also check the lifespan of any of the variables using the storage class in C


Now, apart from learning what is a storage class in C, as a programmer, you are also required to learn about the different types of storage classes that are available in C programming. 

Have a look at these types in the next portion of the blog.


What are the different types of Storage Classes available in C?

As it has been previously mentioned in the blog, there are essentially four different types of storage classes that are available in C programming. Check them out as follows:

  • The Automatic Storage Classes 

This is basically the default storage class in C programming. Each of the variables that are defined within a function are directly allocated to the automatic storage classes. 

Keep in mind that this can only happen if no other storage classes have been mentioned by the programmer while compiling the program.

The functions that are involved within automatic storage class can only be declared using an auto specifier. Also, the variables or functions that are found under the auto in C are the default settings of the block. 

This means that they can only be defined or discarded outside of the block.


Here's how you can implement the automatic storage classes in C:

  • Start with defining each variable within a different block
  • Use the ‘printf' function for printing the program without any form of errors
  • The variable that has been declared within the block will get automatically deleted
  • The system will then print the second block and thus you can see the initialisation of the automatic variables

  • Register Storage Classes

This is yet another form of storage classes in C that makes use of the abstract data types in C++. Here in this storage class the variables are equivalent to the auto in C. 

The only difference between this storage class and the others is that the variables from this class are specifically stored within the CPU registers rather than the memory. Which is why it is referred to as the register storage class.

The functions that are stored within this class can be destroyed once the program is completed.


Check out the process of implementing this class in C:

  • The program will initiate the process of fetching the value of the variable from its pointer. 
  • Next, the program will filter the variables that are stored within the registers. Keep in mind that only these form of variables can be printed by the program

  • Static Storage Classes

One of the most interesting facts about the Static Storage Classes is that the values of the variables within this class are stored between the calls. 

Essentially, you can declare a static storage class with the help of a static specifier. These variables are only found within a file or a function.

Using the Static Storage Class, you can basically store all the locally found variables within the function calls of the program.

Keep in mind that the static storage class will work differently in the context of the local and the global variables.

Check out the implementation of the static storage class as follows:

  • The program will define a static specifier within a block or a function using the compiler
  • Now, using the static local variable, the variables will return the function value within the function calls
  • The function will set up two different locations to place the blocks 
  • Finally, the program will make the last call so that the old values of the variables are not required to be initialized yet again

  • External Storage Classes

As is suggested by the name, the external storage class uses the ‘extern' specifier in order to declare the functions or the variables.

Whenever the program uses an “extern specifier”, the program assumes by itself that a specific storage has already been allocated to the variable.

This particular storage class is only used for the purpose of external linkage.


Here's how you can implement this class in a program:

  • The system checks whether the extern int function has been declared in the program or not
  • Next up, the extern specifier will command the compiler that the variable has been identified 

Wrapping Up

In order to specify the abstract data types in C++, you can check out the storage classes and confirm how the variables are manipulated within a program.

Check out the implementation of each of the storage classes and their respective applications. 


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