ruby : open `join': No live threads left. Deadlock? (fatal)

Question

I am trying to download a picture with open but it fails on a ratio of about 1 / 500 with a deadlock and I do not know why as I do not use threads at all.

The error is :

/usr/lib/ruby/2.3.0/timeout.rb:95:in 'join': No live threads left. Deadlock? (fatal)<br />
from /usr/lib/ruby/2.3.0/timeout.rb:95:in 'ensure in block in timeout'<br />
from /usr/lib/ruby/2.3.0/timeout.rb:95:in 'block in timeout'<br />
from /usr/lib/ruby/2.3.0/timeout.rb:101:in 'timeout'<br />
from /usr/lib/ruby/2.3.0/net/http.rb:878:in 'connect'<br />
from /usr/lib/ruby/2.3.0/net/http.rb:863:in 'do_start'<br />
from /usr/lib/ruby/2.3.0/net/http.rb:852:in 'start'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:319:in 'open_http'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:737:in 'buffer_open'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:212:in 'block in open_loop'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:210:in 'catch'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:210:in 'open_loop'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:151:in 'open_uri'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:717:in 'open'<br />
from /usr/lib/ruby/2.3.0/open-uri.rb:35:in 'open'<br />
from /home/mat/travail_perso/utils.rb:80:in get_pic'<br />

Here is the function that causes the issue :

def get_pic(link)
  tries ||= 25
  begin
    page = open(link, "User-Agent" => "Ruby/#{RUBY_VERSION}")
  rescue => error
    if tries > 0
        tries -= 1
        sleep(0.75)
        retry
    else
      puts 'could nor get picture ' + link + ' after ' + $nb_tries.to_s + ' tries'
      puts error.message
      return nil
    end
  end
  sleep(0.25)
  return page
end

I am still a beginner in RUBY and do not know how to fix that issue as the only results I get when looking for answers are issues with threads which I am not using.
Any help will be greatly appreciated thank you.

The language isn't called "RUBY". It's a proper noun, not an acronym. — Nic, May 22 '16 at 21:36
Also, please show the code that calls this function, the code that sets `$failure` and `$between_sleep`, `$nb_tries`, and so on. It's very difficult to get a picture of what's going on. — Nic, May 22 '16 at 21:37
I see from your stack trace that you're using `timeout.rb`. That's probably the culprit; it can leak resources. You should read [Ruby's Most Dangerous API](http://www.mikeperham.com/2015/05/08/timeout-rubys-most-dangerous-api/) and then switch your code to use socket-based timeouts rather than wrapping your network calls in timeouts. — Chris Heald, May 22 '16 at 22:03
the reason why I did not show the calling functions is that it is called by a lot of them and the error happens with any of them. — Matthieu Raynaud de Fitte, May 22 '16 at 22:08
I replaced the variables with the values thay always have => $between_sleep and $nb_tries are global numbers that are set at the beginning of the programm — Matthieu Raynaud de Fitte, May 22 '16 at 22:11
the complete code is here : https://github.com/Hellfire01/MangaScrapp and the file is utils.rb — Matthieu Raynaud de Fitte, May 22 '16 at 22:11
@MatthieuRaynauddeFitte that's not where the error is coming from, however, have you heard of `optparse`? — 13aal, May 22 '16 at 22:37
I know the error comes from the usage I make from open ( that in turn uses timeout ) but I do not know how to correct it — Matthieu Raynaud de Fitte, May 22 '16 at 22:43
Are you trying to use `nokogiri`s open? Or `open-uri`s open? — 13aal, May 22 '16 at 23:15

ruby : open `join': No live threads left. Deadlock? (fatal)

0 Answers0