- With this post we are moving on to the advance topics of C language.
- In this post, I am going to discuss one of the most important concept of modern programming languages i.e Function. So let’s dive in.
A function is a block of code that performs a specific task.
- When a set of related executable statements are places within a group then it is referred to as function.
- We can use functions for the operations which are need to be repeated.
C functions can be classified into two categories:
- Library Functions
- User-defined Functions (UDF)
- Library functions are provided by the C programming language.
- They are also knows as in-built or ready-made functions.
- User need not to define them. User can directly use them in the program.
- Some examples of library functions are : printf(), scanf(), strlen(), gets(), clrscr(), etc.
User-defined Functions (UDF)
- User-defined functions are those functions which are written by the user (programmer).
- Similar to variables, they need to be defined before using them because compiler dos not have knowledge about them.
- main() is an example of user-defined functions.
Advantages of Functions ( Need for UDF)
- One of the major advantages of functions is re-usability.
- There are situations in which we need to perform some operations or calculations multiple times. If we do not use functions, we have to rewrite that code again and again.
- In such cases, function helps a lot. We can reuse the code which is already written. There is no need to rewrite that code again and again.
- Function works on the principle “write once, use multiple times”
- So this way, we have to write the functions once and it can be used for multiple times.
- Function provides modularity into program by dividing large programs into smaller parts called modules.
- These modules can easily be coded, tested and debugged separately.
- Development will be fast since modules can be assigned to multiple programmers.
- Each programmer is responsible to code, test and debug modules assigned to him or her only.
- Programmers can work on the different modules of the same projects simultaneously.
- Programs divided into functions can be easily debugged.
- Since programs are sub-divided into modules, individual modules are coded, tested and debugged separately.
- If any error is found or modules do not work properly, we only need to check the modules responsible for that task.
- We need not to check the whole program starting from the scratch.
- Since each module is small and implements limited functionality, they are easy to code, debug and modify.
- It saves both time and labor.
- Project management becomes easy as different modules are assigned to different team of programmers.
- Programmers can work on separate modules simultaneously on the same projects.
- Since task is divided into smaller modules, it becomes easy to handle and manage.
- Programs are divided into different smaller modules and these modules further can be sub-divided for better understanding.
- Programs written through functions allow better readability.
- They are easy to read and understand.
- It helps to understand program flow and logic.
That’s it for this post. Elements of Function will be discussed in the next post so please stay tuned!