Ruby » Ruby master

io/wait: add IO#wait_writable method

• ext/io/wait/wait.c (io_wait_writable): this is easier to use than
  IO.select for a single IO object and is immune to the
  limitations/innefficiency of select() on platforms where poll/ppoll
  is available. patched by Eric Wong. [Feature #4646]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37785 b2dd03c8-39d4-4d8f-98ff-823fe69b080e