In article <200706231809.39921.jesse.d.merriman / gmail.com>,
  Jesse Merriman <jesse.d.merriman / gmail.com> writes:

> WTF? If I use "ls" instead of "maxima --batch-string='1+1;'" then it works it
> both cases. So is this a problem with Maxima, Ruby, or my code?

I think it is caused by that maxima is slower than ls.

Try "sleep 1; ls".

It is impossible to read a line before a line is sent in
non-blocking manner.
-- 
Tanaka Akira