Here is an updated version that looks for two specific prompts coming from STDOUT and popping up a dialog to deal with them. The implementations of those dialogs is crude --no validation; minimalistic gui; my Tk is pretty simplistic -- but they are a demonstration only. You can enhance to your hearts desire.

Again, the simplistic command line app:

#! perl -slw
use strict;
use threads;

our $GUI //= 0;

if( $GUI ) {
    require 'MyGui.pm';
    async( \&MyGui::gui )->detach;
}

while( 1 ) {
    printf 'Enter three, 2-digit numbers: ';
    my $in = scalar <STDIN>;
    exit if $in =~ '!bye';
    print 'You entered: ', $in;

    printf 'Enter a date and time: ';
    $in = scalar <STDIN>;
    exit if $in =~ '!bye';
    print 'You entered: ', $in;
}
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Updated: Improved the code below a little.

And the gui module to service it it when the -GUI command line option is supplied:

package MyGuiStdin;
our @ISA = qw[ Thread::Queue ];

sub TIEHANDLE { bless $_[1], $_[0]; }
sub READLINE { $_[0]->dequeue(); }

package MyGuiStdout;
our @ISA = qw[ Thread::Queue ];

sub TIEHANDLE { bless $_[1], $_[0]; }
sub PRINT  { $_[0]->enqueue( join ' ', @_[ 1 .. $#_ ] ); }
sub PRINTF { $_[0]->enqueue( sprintf $_[1], @_[ 2 .. $#_ ] ); }

package MyGui;
use strict;
use warnings;
use threads;
use Thread::Queue;

my $Qin  = new Thread::Queue;
my $Qout = new Thread::Queue;

tie *STDIN,  'MyGuiStdin',  $Qin;
tie *STDOUT, 'MyGuiStdout', $Qout;


sub gui {
    require Tk;
    require Tk::DialogBox;

    my $mw = Tk::MainWindow->new;
    my $lb = $mw->Listbox( -width => 80, -height => 24 )->pack;
    my $ef = $mw->Entry( -width => 70, -takefocus => 1 )->pack( -side 
+=> 'left' );

    my $enter = sub {
        $Qin->enqueue( $ef->get );
        $ef->delete(0, 'end' );
        1;
    };

    my $do = $mw->Button( -text => 'go', -command => $enter)->pack( -a
+fter => $ef );
    $mw->bind( '<Return>', $enter );
    $ef->focus( -force );

    my $doStdout = sub {
        if( $Qout->pending ) {
            my $output = $Qout->dequeue;
            $lb->insert( 'end', $output ) ;
            $lb->see( 'end' );

            if( $output eq 'Enter three, 2-digit numbers: ' ) {
                my $db = $mw->DialogBox( -title => 'Three 2 digit numb
+ers', -buttons => [ 'Ok' ] );

                my $e1 = $db->add( 'Entry', -width => 3 )->pack( -side
+ => 'left' );
                my $e2 = $db->add( 'Entry', -width => 3 )->pack( -side
+ => 'left', -after => $e1 );
                my $e3 = $db->add( 'Entry', -width => 3 )->pack( -side
+ => 'left', -after => $e2 );

                $e1->focus( -force );
                $db->Show;
                my $input = sprintf "%2d %2d %2d", $e1->get, $e2->get,
+ $e3->get;

                $Qin->enqueue( $input );
            }
            elsif( $output eq 'Enter a date and time: ' ) {
                my $db = $mw->DialogBox( -title => 'Date&time', -butto
+ns => [ 'Ok' ] );

                my $day = $db->add( 'Entry', -width => 2 )->pack( -sid
+e => 'left' );
                my $mon = $db->add( 'Entry', -width => 2 )->pack( -sid
+e => 'left', -after => $day );
                my $year= $db->add( 'Entry', -width => 4 )->pack( -sid
+e => 'left', -after => $mon );

                my $hours = $db->add( 'Entry', -width => 3 )->pack( -s
+ide => 'left' );
                my $mins  = $db->add( 'Entry', -width => 3 )->pack( -s
+ide => 'left', -after => $hours );
                my $secs  = $db->add( 'Entry', -width => 3 )->pack( -s
+ide => 'left', -after => $mins );

                $day->focus( -force );
                $db->Show;
                my $input = sprintf "%2d/%02d/%02d %2d:%02d:%02d",
                    $day->get, $mon->get, $year->get, $hours->get, $mi
+ns->get, $secs->get;

                $Qin->enqueue( $input );
            }
        }
    };

    $mw->repeat( 500, $doStdout );

    Tk::MainLoop();
}

1;
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