Command line parameters c++ [duplicate]

Answer 1

Command line arguments are arguments passed to your program with its name. For example, the UNIX program cp (copies two files) has the following command line arguments:

cp SOURCE DEST

You can access the command line arguments with argc and argv:

int main(int argc, char *argv[])
{
    return 0;
}

argc is the number of arguments, including the program name, and argv is the array of strings containing the arguments. argv[0] is the program name, and argv[argc] is guaranteed to be a NULL pointer.

So the cp program can be implemented as such:

int main(int argc, char *argv[])
{
    char *src = argv[1];
    char *dest = argv[2];

    cpy(dest, src);
}

They do not have to be named argc and argv; they can have any name you want, though traditionally they are called that.