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main() Function And Its Necessity For C Programming

    All c language must have a main() function. It's the core of every program. The main() function doesn't really have to do anything other than be present inside your 'C' source code.Eventually, it contains instructions that tell the computer to carry out whatever task your program is designed to do. abut it's not officially required to do anythings.
   
    
      The main() function uses its parentheses to contain any information typed after the program name at the command prompt. This is useful for more advanced programming.
      
      Beginning programmers should keep in mind what those parentheses are there for , but you should first build up your understanding of c before you dive into that quagmire.
    
    The braces are used for organization. They contains programming instructions that belong to the function. Those programming instructions are how the function carries out its task or does its thing.

      Main function is very necessary for C programming because we can compile individual files without main() ,but we cannot link them and of course run them since they are not complete programs. Not that valgrind is not a static analysis tool but a run time tool, and therefore it is useless on individual translation units not linked into a runnable program.
     
       Not that the basic , simple main() function doesn't required specific keyword or procedure for ending the program languages , an END or EXIT command is required, but not in C. In the C language , the program ends when it encounters the last brace in the main() function . That's the sign that the program is done , after which control returns to the operating system.
   
    In other words main() function is the entry point of any C program. It is the point at which  execution of program is started. when a C program is executed , the execution control  goes directly to the main() function.
   
     Every C program have a main() function.
   The syntax for main() function is :-

 void main()
   {
   ...........
.............
...........

}

Here, void is a keyword in C language , void means nothing, whenever we use void as a function returns type then that function nothing return. Here main() function no return any value.
  
    In place of void we can also use int return type of main() function , at that time main() return integer type value.
   
     Main is a name of function which is predefined function in c library of C language program. And very necessary for programming.

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