Hi,

In message "Re: [ruby-core:19668] [Bug #703] string output duplication occurs if the same file descriptor written to in different threads"
    on Sat, 1 Nov 2008 02:38:52 +0900, Roger Pack <redmine / ruby-lang.org> writes:

|ruby-dev:32566

It's not related to ruby-dev:32566, I think.

|a = Thread.new { p '4'}
|b = Thread.new { p '3' }
|a.join
|b.join
|
|results in
|"4"
|"3"
|"4"
|"3"
|
|because the buffer is modified simultaneously by two threads within io_fflush [I think].

It doesn't happen on either trunk nor 1.8.7.  What's your version, and
platform?

							matz.