Description: 04/04/2002 Unix users understand the power of the command line. On the command line you can pass arguments to your applications as easily as you would pass an argument to a function. Standard Unix convention is to pass arguments prefixed by a - or -- . Some options can be specified in more than one way -f or --file , for example. Some can be combined, like GNU\'s tar, -xvfz , to verbosely expand a compressed file. The more options you have, the more code you need to parse them properly.