I am confused. Why do you need to exec if the code is Perl anyway and you have control of both processes and the source for both? 
package MeMz;
use warnings;
use strict;

use vars qw(@ISA @EXPORT_OK);
@ISA = qw(Exporter);

# inherit the import() from Exporter.pm 
@EXPORT_OK = qw();

# list of things to export if asked to 

if (fork() == 0) {
    require Tk;
    my $mw = new MainWindow;
    $mw->overrideredirect(1);
    my $t = $mw->Label(-text => '', -bg => 'black', -fg => 'yellow')->
+pack;

    my $id = Tk::After->new($mw, 1000, 'repeat', [ \&refresh, $pid ]);

    Tk::MainLoop();

    sub refresh {
        my $pid = shift;
        my @size = split "\n", `cat /proc/$pid/status`;
        (my $vmsize) = grep { /VmSize/ } @size;
        my (undef, $size) = split '   ', $vmsize;
        $t->configure(-text => "PID: $pid ->  $size");
        if ($size eq '') { Tk::exit }
    }
}

1;

[download]
Update: s/MainLoop/Tk::MainLoop()/

Makeshifts last the longest.

In reply to Re: fork and exec a codeblock by Aristotle
in thread fork and exec a codeblock by zentara

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