git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@31845 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merges r28557 from trunk into ruby_1_9_2. Fixes #4506.¶
to avoid select() on a socket which TCP state is CLOSED.
patch by Eric Wong. [ruby-core:31053]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@31845 b2dd03c8-39d4-4d8f-98ff-823fe69b080e