From: Dave Thomas <dave@...>
Date: 2008-11-04T03:54:38+09:00
Subject: [ruby-core:19687] Re: [Bug #694] eof? call on a pty IO object causes application to exit


On Oct 31, 2008, at 1:39 AM, Dave Thomas wrote:

>
> On Oct 31, 2008, at 12:28 AM, Yukihiro Matsumoto wrote:
>
>> pty uses exceptions to notify the process exit.  In my case, it
>> terminated because I don't have /usr/bin/irb installed (it's renamed
>> to /usr/bin/irb1.8).
>>
>> What do you expect?  Checking eof without raising exception?
>
> That's what 1.8 seems to do.
>
> Here's a slightly different version:
>
> dave[~ 1:39:37] cat t.rb
> require 'pty'
>
> PTY.spawn("/bin/echo hello") do |reader, writer, pid|
>  reader.eof?
>  puts reader.gets
> end
>
> dave[~ 1:39:43] ruby -v t.rb
> ruby 1.8.6 (2008-03-03 patchlevel 114) [universal-darwin9.0]
> hello
>
> dave[~ 1:39:45] /usr/local/rubybook/bin/ruby -v t.rb
> ruby 1.9.0 (2008-10-29 revision 15427) [i386-darwin9.5.0]
> t.rb:4:in `eof?': pty - exited: 731 (PTY::ChildExited)
> 	from t.rb:4:in `block in <main>'
> 	from t.rb:3:in `spawn'
> 	from t.rb:3:in `<main>'


I wonder if the problem is that pty.c doesn't release the global lock,  
and therefore any output from the subthread that's running the shell  
is never seen?


Dave