X-Recipient: archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status: No, hits=-3.5 required=5.0 	tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,SPF_PASS
X-Spam-Check-By: sourceware.org
Message-ID: <4AD34623.7060409@cwilson.fastmail.fm>
Date: Mon, 12 Oct 2009 11:07:15 -0400
From: Charles Wilson <cygwin AT cwilson DOT fastmail DOT fm>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.8.1.23) Gecko/20090812 Thunderbird/2.0.0.23 Mnenhy/0.7.6.666
MIME-Version: 1.0
To: cygwin AT cygwin DOT com
Subject: Re: Cygwin support for large files
References: <D1B1DF404A32164AACB366ADFEA7C0E0032F7D13 AT srv5 DOT stt DOT loc>
In-Reply-To: <D1B1DF404A32164AACB366ADFEA7C0E0032F7D13@srv5.stt.loc>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

Rocco Scappatura wrote:
> I fear that it is the kernel (cygwin engine) that can't manage file
> greater than 4GB.

Cygwin has supported large files since version 1.5.0 (although depending
on context, applications themselves might make unwarranted assumptions
that break large file support, like assuming that file size or offset
fits into a 'long').

> Is there any way to workaround this limitation?

The limitation is in the version of ZIP provided in the cygwin-1.5
distrbution.  ZIP64 support was added in zip-3.0:

> Zip64 support.  This version supports Zip64 archives as described in the
> PKWare AppNote.  These archives use additional fields to support archives
> greater than 2 GB and files in archives over the 2 GB previous limit (4 GB
> on some ports).  The Zip64 format also allows more than 64k entries in an
> archive.  Support by the OS for files larger than 4 GB is needed for Zip to
> create and read large files and archives.  On Unix, Win32, and some other
> ports, large file and Zip64 support is automatically checked for and
> compiled in if available.  Use of Zip64 by Zip is automatic and to maximize
> backward compatibility the Zip64 fields will only be used if needed.  A
> Zip64 archive requires a pkzip 4.5 compatible unzip, such as UnZip 6.0.

What version of ZIP is being used on your remote cygwin machine?

--
Chuck

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple