Raise if the pipe cannot be created, to differentiate with the wrong result
Raise if the pipe cannot be created, to differentiate with the wrong result

eregon/rubyspec,ruby/spec,ruby/rubyspec,ruby/spec,eregon/rubyspec,nobu/rubyspec,nobu/rubyspec,ruby/spec,nobu/rubyspec,ruby/rubyspec,eregon/rubyspec