sharadpro

as we cant use function overloading in c..
then how are
main()
and
main(int argc, char *argv[]) used?

DaWei

You don't have to worry about overloading, since you only use one or another (never two or more). All you have to worry about is what the compiler does with the particular one it encounters. It does well.

__________________
Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code.
Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers

nindoja

is used when arguments need to be passed to your program. Usually this is done from the command prompt, but may also be used when the program is called from another application. Also, using this method you may supply predefined input to your program without hasseling with files or hard-coding them in. (Note: This works with CodeWarrior and I believe Dev-Cpp, although I'm not sure this is standards compliant for it to do so. I have not tested it in GCC or VS)
is used when your program does not require input from outside sources.

grumpy

The main function is a specific case in the standard, and all implementations are required to support both forms (or equivalent). This is not overloading, as Dawei said, which means that your programs are only allowed to use one of them.

nindoja

Grumpy, I think my wording was confusing. What I was saying when I said "I'm not sure if this is standards compliant" I was referring to me using
main(int argc, char *argv[]) to pass input to my program. Of course main(int argc, char *argv[]) is standards compliant, all it is doing is accepting arguments to a function, albeit a function that the compiler calls to begin execution of the program.

grumpy

Using int main(int argc, char *argv[]) is standard if you want your program to accept parameters at startup

In practice, on most hosted implementations such as those under Unix or windows, the input received via the arguments argc and argv typically come from a command line, but the standard does not specifically require that. In fact, the standard is silent on where the information passed in argc and argv comes from .... that is part of the implementation details of your compiler (eg the compiler specific code that sets up a few things, and then calls your main function).