http://www.perlmonks.org?node_id=247248


in reply to Atomic operations in perl and Tk::IO

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

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