main() in C, C++, Java, C#

Question

Is main() (or Main()) in C, C++, Java or C#, a user-defined function or a built-in function?

Answer 1

It is not "built-in" in any language, in a sense that there is no standard implemented-for you main() avialable.

For C/C++/Java, it is a function with a special property, namely, the function that will be called at the start of your program after all the static setup is done. E.g. entire C program's execution path is:

1. Do some initialization code

2. Call main()

3. Exit.

As such, it has a standard declaration (# of parameters passed from command line + array of "strings" - however the language implements that - which are the actual arguments from command line)