start with the basics...

int main(int argc, char*argv[], char*env[])
{
// argc is the number of strings in argv
// argv is an array of strings that you type from the cmd prompt or
//   passed to your program is some other way.  argv[0] is always the
//   name of your program.
// env is the environment strings -- the same as when you type "c:>set " from a cmd prompt.
}