Yes, you can make a Tk popup for information, then have it finish and let the rest of the program run without a gui. When the Tk EventLoop is destroyed, the main program will pickup execution right after the MainLoop line. Usually, nothing is there, and it exists, but check out this example. 
#!/usr/bin/perl
use strict;
use Tk;
use Tk::DialogBox;

my $logincount = 0;
my $mw = new MainWindow();
$mw->withdraw;  #hide main window 
&login;

MainLoop;

#rest of your script 
for(1..100){print "$_\n"; sleep 1}


############################################################### 
sub login{

my $dialog = $mw->DialogBox(
    -title   => "Login",
    -buttons => [ "OK", "Cancel" ]
);

my $server = 'default';
my $servl = $dialog->add(
    "Label",
   -text => 'Server'
)->pack();
my $servd = $dialog->add(
    "Entry",
   -textvariable => \$server

)->pack();

my $name = 'default user';
my $namel = $dialog->add(
    "Label",
    -text => ' Name '
)->pack();
my $named = $dialog->add(
    "Entry",
    -textvariable => \$name
)->pack();

my $passwd;
my $passl = $dialog->add(
    "Label",
    -text => 'Password'
    )->pack();

my $passd = $dialog->add(
    "Entry",
    -show         => "*",
    -textvariable => \$passwd
)->pack();

my $retlog = 0;
if ( $dialog->Show() eq "OK" ) {
    print "$server\t$name\t$passwd\n";    #this line is only for demo 
    #do your stuff here, like reprompt if the  
    #password is bad, or whatever you want 

    # here you would make a callback to a real login sub, 
    # and if it is good, then enable the main gui 
     $retlog = &real_login($server,$name,$passwd);
  }

if($retlog == 1){ $mw->destroy }
     else {
       $logincount++;
       if( $logincount > 3 ) {exit}
       &login;
      }

}

#########################################################3 
sub real_login{
   my($server,$name,$passwd) = @_;

   my $login_stat = 0;
   #do your stuff here... eally tring to connect to server 
   #assume good 
   if( $passwd == 1 ){  $login_stat = 1; }

  return $login_stat;
}
###########################################################

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I'm not really a human, but I play one on earth. flash japh

In reply to Re^3: Suggestions for Tk login screen by zentara
in thread Suggestions for Tk login screen by mhearse

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