From: Simon Strandgaard <0bz63fz3m1qt3001@...>
Date: 2003-05-14T08:38:44+09:00
Subject: Re: RCR for child execution

On Wed, 14 May 2003 09:08:59 +0900, Brian Candler wrote:

> On Tue, May 13, 2003 at 11:33:10PM +0900, Simon Strandgaard wrote:
>> Does it answer the question ?
> 
> No, because it cannot work. If I write
> 
>      s = ""
>      $stdout = StringIO.new(s)
>      pid = fork do
>        exec("ls *.txt")
>      end
>      Process.wait(pid)
> 
> how are you going to modify fork or exec so that it captures the output of
> 'ls' into the StringIO object created earlier?

I luckyly forgot all about this senario... I you can forgive me :-)

StringIO has no filedescriptor that fork() can parse down to the child.
So we must create such filedescriptor.

A pipe and a receiver thread in the parent process should do it. 
Some semaphore protection is probably necessary, But I don't have enough
insight into the core of ruby, so I cannot tell where semaphore protection should
go.  I think this is possible.

This will solve all my problems. Is such patch to ruby realistic ???


--
Simon Strandgaard