I'm having a bit of trouble going the plain Gtk2 route. I'm not sure what's wrong since I mucked around with the code and changed its behaviour a few times already, but it either 1) works until EOF, after which it goes to an infinite loop, or 2) sysreads the whole output on one go.

  my $cmd = [perl => -e => '$|++; for my $i (0..4) { $sum+= $i; print 
+"Line $i: sum = $sum\r\n"; sleep 1;}'];

  my $cb = sub {print "CB: >>" . shift() . "<<\n";}

  open($fh, '-|', @$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;
  });

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In reply to Re^3: Reading non-blockingly / "awk has to be better for something." by Anonymous Monk
in thread Reading non-blockingly / "awk has to be better for something." by Anonymous Monk

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