From: Ryan Davis <ryand-ruby@...>
Date: 2006-08-07T07:19:06+09:00
Subject: Re: How to redirect a string to stdin within code?


On Aug 6, 2006, at 2:59 PM, Christian Neukirchen wrote:

> Alex Young <alex@blackkettle.org> writes:
>
>>> However this seems an IRB issue Logans code just works fine in  
>>> pure ruby
>> Yes...  I can see why it's not allowed in IRB (if you get rid of
>> stdin, how the hell would you use the console? :-), I just don't know
>> why it segfaults.
>
> Just a guess: the readline extensions directly accesses $stdin without
> checking its type.

I think this is probably fixed in newer versions of ruby:

% ruby -v -rstringio -e 'log = StringIO.new("blah"); $stdin = log;  
require "irb"; IRB.start(__FILE__)'
ruby 1.8.3 (2005-09-28) [i386-freebsd4.11]
/usr/local/lib/ruby/1.8/irb/input-method.rb:97: [BUG] Segmentation fault
ruby 1.8.3 (2005-09-28) [i386-freebsd4.11]

Abort trap (core dumped)

versus:

% ruby -v -rstringio -e 'log = StringIO.new("blah"); $stdin = log;  
require "irb"; IRB.start(__FILE__)'
ruby 1.8.4 (2006-03-04) [i686-darwin8.6.2]
Read 100 saved history commands from /Users/ryan/.irb.hist.
Saving 100 history lines to /Users/ryan/.irb.hist.
/usr/local/lib/ruby/1.8/irb/input-method.rb:97:in `readline': wrong  
argument type StringIO (expected File) (TypeError)
         from /usr/local/lib/ruby/1.8/irb/input-method.rb:97:in `gets'
         from /usr/local/lib/ruby/1.8/irb.rb:132:in `eval_input'
         from /usr/local/lib/ruby/1.8/irb.rb:259:in `signal_status'
         from /usr/local/lib/ruby/1.8/irb.rb:131:in `eval_input'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:189:in `buf_input'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:104:in `getc'
         from /usr/local/lib/ruby/1.8/irb/slex.rb:206:in `match_io'
         from /usr/local/lib/ruby/1.8/irb/slex.rb:76:in `match'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:287:in `token'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:263:in `lex'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:234:in  
`each_top_level_statement'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:230:in  
`each_top_level_statement'
         from /usr/local/lib/ruby/1.8/irb/ruby-lex.rb:229:in  
`each_top_level_statement'
         from /usr/local/lib/ruby/1.8/irb.rb:146:in `eval_input'
         from /usr/local/lib/ruby/1.8/irb.rb:70:in `start'
         from /usr/local/lib/ruby/1.8/irb.rb:69:in `start'
         from -e:1