In a Tk gui ( or similarly with other GUI toolkits) you can catch the X button. 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = new MainWindow;
$mw->title("Close test");
$mw->geometry("400x250");

#prevents mw from closing
$mw->protocol('WM_DELETE_WINDOW' => sub {
                print "do stuff here before the exit\n";
        exit;
           });

MainLoop;

[download]
If you are just running an xterm , I don't know if it's possible easily. You probably would have to incorporate Term::ReadKey into your script and manually filter the keys.
I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

In reply to Re: Catching WINDOW close event and take actions by zentara
in thread Catching WINDOW close event and take actions by Anonymous Monk

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