Here's a self-contained version of that code.
use Gtk2 '-init';
use Gtk2::Helper;
use Glib qw/TRUE FALSE/;
use IO::Handle;
my $cmd = [perl => -e => '$|++; for my $i (0..4) { $sum+= $i; print
+"Line $i: sum = $sum\r"; sleep 1;}'];
my $cb = sub {print "CB: >>" . shift() . "<<\n";};
open(my $fh, '-|', @$cmd) or die "failed to launch external command:
+ $!";
$fh->blocking(0);
$tag = Gtk2::Helper->add_watch($fh->fileno, in => sub {
if ($fh->eof) {
print "pipe EOF\n";
Gtk2::Helper->remove_watch($tag);
close $fh;
return;
}
while (1) {
my $buf;
$fh->sysread($buf, 4095);
print "READ: >>$buf<<\n";
last unless $buf;
for (split(/[\r\n]/, $buf)) {
$cb->($_);
}
}
# keep watch active
return TRUE;
});
Gtk2->main;
It goes into EOF-loop if it says last unless $buf, and into slurp mode if it says return FALSE unless $buf