Hi, I'm not clear what you mean to receive commands from some other program while it is doing its thing? There may be a better way than tailing the output of the program and processing it for commands. Something like IPC::Open3 might be better than tailing, but it all depends on your program.

Anyways, with the lack of details, I think you probably need to kill the $pid of program_ipc, otherwise post details of what this program outputs, and how it operates.

In the meantime, try something like the following, and remember, you may need to use Proc::Killfam instead of a plain kill, depending on whether you get the pid of any shell running the program. 

#!/usr/bin/perl
# tktail pathname
use warnings;
use strict;
use Tk;

my $pid = open(H, "tail -f -n 25 $ARGV[0]|") or die ;

my $mw = MainWindow->new;
my $t = $mw->Text(-width => 80, -height => 25, -wrap => 'none');
$t->pack(-expand => 1);
$mw->fileevent('H', 'readable', [\&fill_text_widget, $t]);
$mw->OnDestroy(\&quitCB);
MainLoop;

sub fill_text_widget {
my($widget) = @_;
my $text = <H>;
$widget->insert('end', $text);
$widget->yview('end');
} # end fill_text_widget

sub quitCB {
kill 9,$pid or die $!;
exit;
}

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In reply to Re: Perl non-blocking IPC by zentara
in thread Perl non-blocking IPC by brian42miller

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