'rbuf_fill': execution expired (Timeout::Error)

Sun Dec 09 04:41:00 -0800 2007

This is a fun little exception in Ruby that you have to catch explicitly in order to get hold of it in a rescue block.

Say you had the following:

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require 'net/pop3'
begin
  Net::POP3.auth_only(@server, @port, @username, @password)
rescue => e
  write_error_to_logfile(e)
  do_something_sensible
end

And the mail server could not be reached due to transient network problems -> that is, you are getting a socket timeout error.

Well, your code in the rescue block won’t get executed! Even though the script raises an Error!

Why is this?

Simple answer, because Timeout::Error is not a subclass of StandardError, it is a subclass of the Interrupt class.

So, that means you have to catch it explicitly, like so:

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require 'net/pop3'
begin
  Net::POP3.auth_only(@server, @port, @username, @password)
rescue => e
  write_error_to_logfile(e)
  do_something_sensible
rescue Timeout::Error => e
  write_error_to_logfile(e)
  do_something_sensible_for_timeout
end

And all will be good again, error caught!

blogLater

Mikel

  1. xuxu Says:
    Mon Dec 17 11:10:09 -0800 2007

    Thank you very much ;)

  2. Bryn Thomas Says:
    Thu Jan 10 17:14:02 -0800 2008

    Thanks, I had this same error and this cleared up my incorrect expectation that everything derived from a root Exception class.

  3. Colin Curtin Says:
    Mon Jan 28 22:57:55 -0800 2008

    http://blog.nicksieger.com/articles/2006/09/06/rubys-exception-hierarchy

    Every exception derives from Exception, so you can do

    begin # Thing that throws Timeouts, anything… rescue Exception => e puts ”#{e}\n#{e.backtrace.join(”\n”)}” end

  4. dace Says:
    Wed Feb 20 02:14:41 -0800 2008

    this was a huge help!

  5. Jan Rüegg Says:
    Fri Feb 29 14:43:10 -0800 2008

    This was e great help to me too… Thanks a lot!

  6. Robert Aganauskas Says:
    Thu Mar 13 21:01:33 -0700 2008

    Thanks, this error was really driving me crazy.

  7. Jarek Says:
    Thu Jun 12 20:23:40 -0700 2008

    Thanks !

  8. Roob Says:
    Mon Aug 25 23:20:00 -0700 2008

    that was very helpful, thanks!

  9. Murali Says:
    Wed Sep 10 17:54:23 -0700 2008

    Thanks. this saved my debugging time.

  10. Dirceu Jr. Says:
    Thu Sep 25 07:54:57 -0700 2008

    Thx!!!

  11. wc Says:
    Thu Nov 06 18:04:26 -0800 2008

    thank you, this was very helpful

  12. Tudor Constantin Says:
    Sat Dec 06 07:06:08 -0800 2008

    This was a great help. Small, concise, exactly what I needed. Thx alot

  13. Chris Says:
    Mon May 11 20:51:54 -0700 2009

    Very helpful – accurate and to the point. Thank you!

  14. Jon Says:
    Wed Jun 10 04:36:57 -0700 2009

    Thanks! Found this on first google search, instantly fixed!

  15. Dan D Says:
    Mon Jul 06 15:57:55 -0700 2009

    Thank you very much. But…. so lame…

  16. John Says:
    Sun Aug 16 23:52:29 -0700 2009

    You should not have a catch-all rescue anyway.

    “rescue => e” == EVIL.

  17. dubek Says:
    Mon Aug 17 03:16:19 -0700 2009

    @Colin

    You don’t want to rescue Exception, because then even the syntax errors in your code will be rescued by the rescue clause.

    I still don’t understand why the Timeout exceptions aren’t a subclass of StandardError…

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