Using Getopt::Long to call one or more Subroutines..

How do I use Getopt::Long to call one or more sub routines in my program?


__Code__

GetOptions( "one" => .....sub1().... ,
            "two"  => .....sub2()....,
             "three" => ....sub3().... );


sub sub1 {
print "sub one";
}

sub sub2{
print "sub two";
}

sub sub3 {
print "sub three";
}

__End Code__

Also I read in the Getopt::Long's perldoc that you need to use "Permute" to set a subroutine as default if no arguement is passed in the command line.  How would I make it so that subroutine sub1 is called when not arguement is given in the commandline.