assert_finish 5, %q{
  r, w = IO.pipe
  t1 = Thread.new { r.sysread(1) }
  t2 = Thread.new { r.sysread(1) }
  sleep 0.1
  w.write "a"
  sleep 0.1
  w.write "a"
}, '[ruby-dev:31866]'

assert_finish 10, %q{
  begin
    require "io/nonblock"
    r, w = IO.pipe
    w.nonblock = true
    w.write_nonblock("a" * 100000)
    w.nonblock = false
    t1 = Thread.new { w.write("b" * 4096) }
    t2 = Thread.new { w.write("c" * 4096) }
    sleep 0.5
    r.sysread(4096).length
    sleep 0.5
    r.sysread(4096).length
    t1.join
    t2.join
  rescue LoadError
  end
}, '[ruby-dev:32566]'

assert_finish 1, %q{
  r, w = IO.pipe
  Thread.new {
  w << "ab"
  sleep 0.1
  w << "ab"
  }
  r.gets("abab")
}