From: Eric Hodel <drbrain@...7.net>
Date: 2006-12-08T05:31:38+09:00
Subject: Re: NoMethodError in protocol.rb

On Dec 7, 2006, at 02:13 , Alex Young wrote:

> Does this look familiar to anyone?
>
> NoMethodError: undefined method `+' for nil:NilClass at /usr/local/ 
> lib/ruby/1.8/net/protocol.rb:176:in `write0'
>
> I'm getting it sporadically during some fairly heavy XMLRPC  
> traffic.  It doesn't make very much sense to me, because write0  
> looks like this:
>
> def write0(str)
>   @debug_output << str.dump if @debug_output
>   len = @io.write(str)
>   @written_bytes += len  # <= line 176
>   len
> end
>
> The error must mean that @written_bytes is nil.  It's only called  
> from within a block passed to writing, which looks like this:
>
> def writing
>   @written_bytes = 0
>   @debug_output << '<- ' if @debug_output
>   yield
>   @debug_output << "\n" if @debug_output
>   bytes = @written_bytes
>   @written_bytes = nil

Yes, this is going to be a problem in a multithreaded environment.

>   bytes
> end
>
> Is this a known thread-safety issue with a known solution, or would  
> a patch be in order?  I've been testing this on 1.8.4, because  
> that's what we've got in production.

I've not heard of it before.

> Does anyone know if it's been addressed in 1.8.5?

Doubtful.

-- 
Eric Hodel - drbrain@segment7.net - http://blog.segment7.net

I LIT YOUR GEM ON FIRE!