io.c: discard buffer always
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49765 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
io.c: discard buffer always
exit or exception.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49765 b2dd03c8-39d4-4d8f-98ff-823fe69b080e