#### 22.6.2 Accessing Command-Line Parameters ¶

If the program was invoked with any command-line arguments, it can access them through the arguments of `main`, `argc` and `argv`. (You can give these arguments any names, but the names `argc` and `argv` are customary.)

The value of `argv` is an array containing all of the command-line arguments as strings, with the name of the command invoked as the first string. `argc` is an integer that says how many strings `argv` contains. Here is an example of accessing the command-line parameters, retrieving the program’s name and checking for the standard `--version` and `--help` options:

    #include <string.h> /* Declare strcmp. */

    int
    main (int argc, char *argv[])
    {
      char *program_name = argv[0];

      for (int i = 1; i < argc; i++)
        {
          if (!strcmp (argv[i], "--version"))
            {
              /* Print version information and exit. */
              ...
            }
          else if (!strcmp (argv[i], "--help"))
            {
              /* Print help information and exit. */
              ...
            }
        }
      ...
    }