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I am testing a perl/tk code to display log file on my tk text window. It works correctly when I first clicked the start button, but out of lock when I try it again and my code gave me an even error:

Tk::Error: Can't locate object method "OPEN" via package "Tk::Event::IO" at fileeventXu1.pl line 81.

I had tried for a couple of days but out of luck:

Any help will be greatly appreciated.

Yuan

Here is my code:

use English;

use Tk;

use FileHandle;

use strict;

use warnings;

use vars qw($IPC_win);

#

my $dir = "~/perl/nodia/junk1";

my $out = "Test_diamod.out";

my $IPC_win = MainWindow->new;

my $title = "Diamod running status";

my $txt1 = "Start Diamod";

my $i = 0;

my $color = "red";

my $stop = "stop";

#

#

$IPC_win -> title("$title");

#

my $text = $IPC_win -> Scrolled("Text",

-width => 90,

-height => 25,

-wrap => 'none') -> pack(-side => 'top',

-expand => 1,

-fill => 'both');

#

my $close = $IPC_win -> Button(-text => "Close Window",

-activeforeground => "blue",

-command => sub {destroy $IPC_win;});



#

my $status = $IPC_win->Label(-text=>"Information:",

-relief => "sunken",

-borderwidth=> 2,

-anchor => "w",

-wraplength => 0

);

#

my $start_button = $IPC_win -> Button(-text => "$txt1",

-activeforeground => "red",

-command => sub{diamod()});

$status->pack(-side => 'bottom',

-expand => 0,

-fill =>'both'

);

#

$start_button -> pack(-side => 'left', -expand => 1, -fill => 'both');

$close -> pack(-side => 'left', -expand => 1, -fill => 'both');

#

MainLoop;

#

# ---------------------------

sub diamod{

#

my $i = ++$i;

if ($i > 1){$color = "blue";};

chdir ($dir);

#

&openfile($i);

my $text = " Running diamod program, it takes a while to finish.";

$status -> configure(-text => $text,

-foreground => $color,

-justify => 'left',

-font => "Arial 14 normal");

#

#

} #End sub diamod

#

sub fill_text_widget {

#

my($stat,$data);

$stat = sysread H, $data, 256;

die "sysread error: $!" unless defined $stat;

$text -> insert('end', $data);

$text -> yview('end');

} # end fill_text_widget

#

sub openfile {

print STDOUT "I am here, $_[0], $dir/$out\n";

#

open(H, "tail -f -n 20 $dir/$out& | ") or die "Nope: $OS_ERROR";

$IPC_win ->fileevent(\*H, 'readable', [\&fill_text_widget, $text]);

} # end fill_text_widget

1;