From: Tanaka Akira <akr@...>
Date: 2013-04-06T00:19:10+09:00
Subject: Re: Exception Errno::EWOULDBLOCK in net/protocol.rb

2013/4/5 Michel Demazure <lists@ruby-forum.com>:
> I am using the 'rsolr' library on ruby-1.9.3 (Windows 7 64 bits) to
> access the BITNAMI/Apache/Solr stack running on my desktop. When adding
> records to the index, I sometimes get the exception below (but the
> addition is correct, and my code works OK) :
>
> Exception `Errno::EWOULDBLOCK' at
> C:/Ruby193/lib/ruby/1.9.1/net/protocol.rb:141 ... read would block
>
> The culprit is :
>
>     def rbuf_fill # net/protocol.rb, line 139
>       begin
>         @rbuf << @io.read_nonblock(BUFSIZE) # line 141
>       rescue IO::WaitReadable
>         ...
>       rescue IO::WaitWritable
>         ...
>       end
>     end
>
> which rescues IO::WaitReadable and IO::WaitWritable, but not
> EWOULDBLOCK. I wonder whether I do something wrong (should I rescue it
> ?) or it is a weakness of the Net library (on Windows maybe ?).

I'm not sure what happen.

However the expected mechanism is follows.

IO::WaitReadable and IO::WaitWritable are modules.
IO#read_nonblock should raise an exception, EWOULDBLOCK for example, extended by
IO::WaitReadable or IO::WaitWritable.
So the rescue clauses should trap the exception.
-- 
Tanaka Akira