int main(int argc, char* argv[]) -- WTF?

[Falco Girgis]

I don't want to be flamed; insulted; or be called called gay, the antichrist, etc.

I have never come upon a main function that looks like this:

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int main(int argc, char* argv[])

in all of my C++ book learning days. I've never seen that before. Now, it is being used in Dev-C++ default and same with VC++.

I alwasy see:

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int main()

Somebody want to tell me what the hell that stuff is?

[Don Pwnious]

As I'm sure you already know the function main is the entry point into your program. The int before it shows that it returns an integer. Normally this would return to a function in your program but the return from main goes to the operating system. Generally main should just return 0 which means it exited successfully but you can return other codes for other situation.

The two arguments it takes int argc and char *argv[] refer to the commandline arguments specified to the program. argc holds the number of arguments (including the program's name) and argv holds the arguments as an array of arrays of characters. (A list of strings).

So if you were to run the program foo with the arguments "-a bar 2" then argc would be equal to 4 (3 arguments and the program name) and argv would contain ["foo", "-a", "bar", "2"] so you could do something like -

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for (int i=0; i<argc; i++)
  cout << argv[i];

This would cause the program to dump the variables to the terminal.

[MarauderIIC]

I thought I mentioned that to you. Maybe I only mentioned it to Phel.