Bug #4024: IO#readlines(0) never return
http://redmine.ruby-lang.org/issues/show/4024
$B5/I<<T(B: Tomoyuki C.
$B%9%F!<%?%9(B: Open, $BM%@john(B: Normal
$B%+%F%4%j(B: core
ruby -v: ruby 1.9.3dev (2010-11-04 trunk 29690) [x86_64-darwin10.4.0]
1.9.2 $B$*$h$S(B trunk $B$G(B IO#readlines $B$N0z?t$K(B 0
$B$rEO$9$HL58B%k!<%W>uBV$K$J$j