******** fig4.6 **********

	void
	list_directory( Directory_or_file D )
	{
		list_dir( D, 0 );
	}

	void
	list_dir( Directory_or_file D, unsigned int depth )
	{
/*1*/		if( D is a legitimate entry )
		{
/*2*/			print_name( depth, D );
/*3*/			if( D is a directory )
/*4*/				for each child, c, of D
/*5*/					list_dir( c, depth+1 );
		}
	}