From: "Ara.T.Howard" <Ara.T.Howard@...>
Date: 2005-06-29T05:54:40+09:00
Subject: Re: C-like ugliness of Kernel#select

On Wed, 29 Jun 2005, C Erler wrote:

> IO has such methods as #closed? and #eof? to find much-needed information
> about IO status, but it doesn't have anything like #read_ready? or
> #write_ready? that would be useful for anyone not wanting blocking IO. The
> only way to do this is with the C-like ugly-hackishness that is
> Kernel#select.
>
> Does anyone have a good argument for not adding a few more methods to IO in
> the Ruby distribution itself ? Does anybody think it would be a good idea to
> submit this as an RCR ? If those are added, would we be able to remove
> Kernel#select in the next "we don't care about backward compatibility" Ruby
> version ?

   harp:~ > cat a.rb
   require 'io/wait'
   STDOUT.sync = true
   pipe = IO::popen 'while true;do sleep 2; echo 42; done'
   threads = []
   threads << Thread::new{ loop{ puts "not blocked @ <#{ Time::now }>"; sleep 0.42 } }
   threads << Thread::new{ loop{ (pipe.ready? and puts("buf <#{ pipe.gets.chomp }>")) or sleep 0.42 } }
   threads.each{|t| t.join}


   harp:~ > ruby a.rb
   not blocked @ <Tue Jun 28 14:52:45 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:45 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:46 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:46 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:47 MDT 2005>
   buf <42>
   not blocked @ <Tue Jun 28 14:52:47 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:48 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:48 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:48 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:49 MDT 2005>
   buf <42>
   not blocked @ <Tue Jun 28 14:52:49 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:50 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:50 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:51 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:51 MDT 2005>
   buf <42>
   not blocked @ <Tue Jun 28 14:52:51 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:52 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:52 MDT 2005>
   not blocked @ <Tue Jun 28 14:52:53 MDT 2005>
   buf <42>
   not blocked @ <Tue Jun 28 14:52:53 MDT 2005>
   ...
   ...
   ...

know yer standard libs ;-)  i don't think this work on windows - but it is in
the standard dist.

hth.

-a
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