Update: <homer_simpson_voice>DOH! cloooosures</homer_simpson_voice>
-- I'll leave the text here so that no else who reads this makes the same mistake. :-)

In your call to component_window(), you assign $pcrh and $pid a la     my ($prch,$pid) = @_; now, I don't see a shift nor a pop nor any other @_ manipulations, which makes your call to tail_lines() incorrect: 

sub component_window {
    my ($prch,$pid) = @_;
    ...
    my $tail = Tk::IO->new( 
       -linecommand => sub { tail_lines($prch, $_[0]) });
    ...
}

sub tail_lines {
    my ($proc,$text) = @_;
    ...
}

[download]
because $_[0] is the same as $prch when you call tail_lines($prch, $_[0]), and this seems to be not what you want.

You should be able to either pass the third element directly or get the third element in a var at the top of your sub (i.e. 

sub component_window {
    my ($prch,$pid,$text)=@_;
    ...

[download]
and pass that... 
    ...
    my $tail = Tk::IO->new( 
       -linecommand => sub { tail_lines($prch, $text) });
    ...
}

[download]

--
hiseldl
What time is it? It's Camel Time!

In reply to Re: Atomic operations in perl and Tk::IO by hiseldl
in thread Atomic operations in perl and Tk::IO by rinceWind

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