Skip to main content

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.

Comments

Popular posts from this blog

Process Scheduling And Types of Process Schedular :-

        ⇰ PROCESS SCHEDULING Process Scheduling  is a task  of Operating System that schedules processes of different states like new, ready, waiting, terminated  and running.This scheduling helps in allocation of CPU time for each process, and Operating System allocates the CPU time for each procss. And the process scheduling plays important role to keep the CPU busy all the time.  ⏩   Followings are some objectives of Process Scheduling :-  i > To increase the amount of users within acceptable response times.  ii > To maintain the balance between response and utilization of system. iii > To decrease the enforce priorities and  give reference to the processes holding the key resources.      ⇰  PROCESS SCHEDULAR A scheduler carries out the pro cess scheduling work. Schedulers are often implemented so they keep all computer resources busy and  allows multiple users to shar...

Process & Its state And process control block :-

                ⇰  PROCESS :- A process can be thought of as a program in execution. Means when any program is executed it becomes process. A processwill need certain resources such as CPU time , memory, files and I/O devices to complete its task. These resources are allocated to the process either when it is created or at the time of execution.             A process is the unit of work in most systems. A system consistes of a collection of processes. All these processes may execute concurrently. Traditionally a process contained only a single thread. Most modern operating ststems now supports processes that have multiple threads.         The operating system is responsible for several important works of process management as - the creation and deletion of process, the schrduling of process, communication and deadlock handling of process. Process is broudly divided into two ...

Tokens and its types in 'C'

   Tokens are the smallest individual unit of a program or in simple words it is a main part of C program.Tokens are the building blocks of any program. The smallest individual and basic unit of a C programming is called c tokens.      *    Normally there are six types of tokens in C:- i> Keywords:-          Keywords are special words that are used to give a special meaning to the program and can't be used as variable and constant.They are basically a sequence of characters that have fixed to mean. For example:-                 auto     double      long     break                 float    short        char     if                while    continue   int       void etc. All...