Using 0.9.9.3 during RSpec any command results in this:
 pry(#<ActionDispatch::Routing::Mapper>)> show-doc
NoMethodError: undefined method `winsize' for #<IO:<STDOUT>>
from (druby://localhost:52574) /Users/kain/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/drb/drb.rb:1548:in `perform_without_block'
It works fine with 0.9.8.4.
I couldn't reproduce the problem without knowing more about your environment, but this should fix it. Thanks for reporting it.
version 0.9.9.4 bugfix release
Fixes `undefined method `winsize' for #<IO:<STDOUT>>` error (#549), and exit breakage on syntax error (#550).
Pager: use TerminalInfo API for `::page_size`
Fix issue #829 (NoMethodError: undefined method `winsize'
for #<IO:<STDOUT>>, The Same Error as #549 But On The Latest Version