Oh divine ones, I'm back. Here's what I'm trying to do. Check out this code: 
# a frame in my Tk main window
my $frame = $mw->Frame;

# a text widget with attached scrollbars in my frame
my $OutputText = $frame->Scrolled('Text', 
   -height => '50', 
   -width => '150', 
   -scrollbars => 'osoe' 
);

# pack frame and text widget
$frame->pack(qw/-side left -fill y/);
$OutputText->pack(qw/-side bottom -fill both -expand 1/);

# here I try to tie STDOUT to the text widget
my $widget = $OutputText->Subwidget("text");
tie *STDOUT, ref $widget, $widget;

[download]
So the idea in the code above is the following: anything printed to STDOUT later on in the program should appear in the text widget. Lo and behold, that works, except for what I assume is a buffering issue.

If I just look at STDOUT, the messages that the program spits out appear on STDOUT as they are printed. Fine. But if I look at my text widget, messages appear only much later (e.g., after we've iterated through a loop). For example, if I do: 
for ( 1..10 ) {
   sleep 10;
   print "foo\n";
}

[download]
I get ten lines of "foo" after 100 seconds on my text widget, while I get a "foo" every 10 seconds on STDOUT.

I assume this is something to do with buffering but I don't quite understand how that works (esp. with respect to tie-ing). I don't think STDOUT is buffered at all? Or line-buffered? Setting STDOUT->autoflush(1) has no effect. What to do?

Thanks for any and all replies!

In reply to Tk::Text and buffering, I think by rvosa

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