Try using an entry widget like so: 
use Tk;
use warnings;
use diagnostics;
use strict;
my $text;
my $mw = MainWindow->new;

$mw->title("PerlRun");

$mw->Entry(-width => 30, -textvariable, \$text)->pack(-anchor => 'nw',
            -side => 'top');

$mw->Button(-text => " Run ",
    -command => \&runprog )
    ->pack(-side => 'left',
    -anchor => 'sw');
$mw->Button(-text => "Done",
    -command => sub { exit })
    ->pack(-side => 'left',
    -anchor => 'sw');

sub runprog {
    system($text);
    }

MainLoop;

[download]
If you wanted to use the Text widget, than your only problem was that you were trying to run the command on the ref to the $text widget instead of the variable in the runprog sub, so.. what you really wanted to do is this:
my $cmd = $text->get('0.1','end'); chomp $cmd; system($cmd);
Take a look at the Mastering Perl/Tk by Steve Liddie... great book :)
Cheers,
JamesNC

In reply to Re: Perl/Tk run program by JamesNC
in thread Perl/Tk run program by st_possenti

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