Tk is almast simple when you have understood basic mechanics.

It can run on very different OS and here around is full of examples and even books.

It seems weird to me mixing a cli application with some gui part: in this case use a command line interface like the yet suggested Ask or doing it by hand reading from STDIN

A full Tk application asking the user for some parameter can look like:

use strict;
use warnings;

use Tk;

my $param = '';

my $mw = Tk::MainWindow->new;

$mw->Label(-text=>'Please enter your parameter:')->pack;

$mw->Entry(-textvariable=>\$param)->pack;

$mw->Button(-text=>'Submit (even if no button are needed',
            -command=>sub{
                print "Button was pressed: \$param is now '$param'\n";
            })->pack;

MainLoop();
[download]

Please note that $param is modified while typing in the Entry not when you hit the Submit button.

L*