storing multiple
argument values (<I>arg_xxx.data)</I> and a count of them
(<I>arg_xxx.count)</I>. Add any other fields you need for your custom
parsing routines as required. Any internal data you would prefer to
hide from the end-user can be stored in a user-defined private data
structure that is encapsulated by the <I>arg_hdr</I> structure as you
will see next.</P>
<PRE CLASS="western">struct arg_xxx_priv
   {
   /* Private custom data goes here */
   ...
   };</PRE><H4>
Defining the argx_xxx constructors