From: "ara.t.howard" <ara.t.howard@...>
Date: 2008-09-10T05:37:16+09:00
Subject: Re: FileUtils.chdir thread safety


On Sep 9, 2008, at 1:46 PM, Joel VanderWerf wrote:

> So in the case of
>
>  Thread.chdir('foo') {puts `ls`}
>
> the subprocess would be executed in foo ?
>
> This would be very nice, but it seems like a major modification to  
> ruby... potentially every system call would need to be aware of the  
> thread cwd state.


this is already true.  if you do

   chdir('foo'){ puts `ls` }

the command will enter foo, run ls, and exit.  the real issue is with

   Thread.new do
     chdir 'foo'
     puts `ls`
   end

   Thread.new do
     chdir 'foo'
     puts `ls`
   end

it's a race condition currently, though i assume that's what you meant  
joel.

a thread local 'chdir' would need to affect backticks, system, exec,  
Dir methods, FileUtils methods, etc.  i guess the first thing  
scheduling each thread would need to do is chdir to it's own cwd  
before running any code to be safe.  this seems *very* expensive  
doesn't it?

it seems like an easier
a @ http://codeforpeople.com/
--
we can deny everything, except that we have the possibility of being  
better. simply reflect on that.
h.h. the 14th dalai lama