From: "Berger, Daniel" <Daniel.Berger@...>
Date: 2006-05-24T05:59:39+09:00
Subject: Atomic File.copy from Linux to Windows shared drive

Hi all,

We've got a Linux box that runs some reports.  When the reports are
finished they're supposed to be copied to a public drive setup via
Samba, with a Samba client on the Linux box and a Samba server setup on
a Windows box somewhere (not available to me).  At least, that's my
understanding of how things are setup. The public drive is mounted as
/X.

The problem is that sometimes the server (or client?) flakes out and
weird stuff happens during File.copy attempts.  In the last incident
only parts of files were copied.  Some operations seemed to just hang.

Here's a synopsis of what I attempted most recently:

require 'ftools'
require 'timeout'

begin
   Timeout.timeout(3){
      File.copy('temp.txt', 'temp.bak')
      File.rename('temp.bak', '/X/temp.txt')
      File.unlink('temp.bak')
   }
rescue Errno::EPERM
   # Ignore bogus EPERM errors - harmless
end

The problem is that File.rename is raising Errno::EXDEV errors, and
simply ignoring those won't work.

So, given that the shared drive could go down in the middle of a
File.copy operation, what are my options here?  Would Ara's posixlock
package help me here?  If so, how would I use it?  It wasn't clear to me
from the docs.

Thanks,

Dan


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