delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2023/12/05/09:48:43

X-Recipient: archive-cygwin AT delorie DOT com
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2071D38449D5
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
s=default; t=1701787722;
bh=ZNAR1G+kpG3CUfjpBMzihWgwpxhygLSSf/BdMyecurs=;
h=Date:Subject:To:References:In-Reply-To:List-Id:List-Unsubscribe:
List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:
From;
b=hhu8IONCbvy2PbxcuUkmM0tMMAQAMU26QMtGUsG0LlqqeL17BwlWAJcZgWo1Et/jY
3PubRd4lbEB8m/jT3mCn8o16dphr4QlsvIQSg/4n3wGgSJkiWRkHpvAiONdEa+6r7Z
LgHZ/00GF3TRISLioI4nEJQhRxDzcidh92n74psU=
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org BA7C93858426
ARC-Filter: OpenARC Filter v1.0.0 sourceware.org BA7C93858426
ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701787686; cv=none;
b=Vz9YuBSmLKUw+n6SNzTwU+hBQZGdXig7CwZ8MXwRVCkQVGFObulPdwv3DZ7qOYFDhIQQVkrCo8WJIEXU6iU/XFqbZVuKRcyYKW9qeqHAa8jqoKW583eEaR2XLthRpV97QYv4jdALPwkcz5jjGQYaRHwS6SydVLctADRfsAv+/u4=
ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key;
t=1701787686; c=relaxed/simple;
bh=XckIl8XnFHNWZs8xlvPMyFVDxP1ORl6kmzC2+dpbG0E=;
h=Message-ID:Date:MIME-Version:Subject:To:From;
b=ghzmDX2wgL4kDxoWUGei0JH5ua4bhE2VSQNtRC3GFkMFbLCgRvCZhEV1l/G7aTmjq7kntiKZd3djHrA2bIory55cB+vCTCJe+6qYOIyWqEgLJw8AGHfwhzSb4C/qf5J8uvNcNbBGoHcLaGPD84fqzJTRkCtGAYGA980ESgFJV+Q=
ARC-Authentication-Results: i=1; server2.sourceware.org
Message-ID: <06bd1d13-7d60-4e45-b597-70816a2ad559@towo.net>
Date: Tue, 5 Dec 2023 15:47:58 +0100
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: Cygwin api to punch a hole into a file?
To: cygwin AT cygwin DOT com
References: <CALXu0Uee2CHeCpthOKFmct+6HnEsKHbSzdK3Jyx8GsnYyt7Lbw AT mail DOT gmail DOT com>
<ZWCCfqny4lC11bBJ AT calimero DOT vinschen DOT de>
<ZWXBH_viPFuSF6be AT calimero DOT vinschen DOT de>
<CALXu0UcLK5AvrYDOg-9L2wFVhvjJuJre6X6GvL+5SyL744eygA AT mail DOT gmail DOT com>
<ZWm9NNUlxdOunBGP AT calimero DOT vinschen DOT de>
<33d4b0df-7a6a-40cf-85a2-9a4300198672 AT towo DOT net>
<ZW8rPaJ5jua08WHH AT calimero DOT vinschen DOT de>
<12e1d9d9-bc56-456e-a1ab-c760987f3ac2 AT towo DOT net>
Autocrypt: addr=towo AT towo DOT net; keydata=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 kQ==
In-Reply-To: <12e1d9d9-bc56-456e-a1ab-c760987f3ac2@towo.net>
X-Provags-ID: V03:K1:IybQodp7ICOd/2upTI0XJVjcGTFJPxYoKbKpA4D35mwYABUPDF1
Kua/7B3254EACMW+AWQ5+Cpitr9tFMXzf+QdgnqQ7uSoDK+9SgoMOmCMMtmL0XypYsxEZkH
VqzCe2yt3LCB1MPRMqq/8IFImA+ywVKfHXlIbXCkBdVdFXby+8z1ihZRb6QuU1h1wvMxUZx
aWOW0Flj7r2uOOvqQ7JTQ==
UI-OutboundReport: notjunk:1;M01:P0:ag8e5tyFBl0=;7L8GOv/jGG1EB0r5upre5REwU9L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X-Spam-Status: No, score=-1.6 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS,
RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP,
T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
server2.sourceware.org
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.30
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe: <https://cygwin.com/mailman/options/cygwin>,
<mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive: <https://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <https://cygwin.com/mailman/listinfo/cygwin>,
<mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From: Thomas Wolff via Cygwin <cygwin AT cygwin DOT com>
Reply-To: Thomas Wolff <towo AT towo DOT net>
Errors-To: cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com
Sender: "Cygwin" <cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com>
X-MIME-Autoconverted: from base64 to 8bit by delorie.com id 3B5EmgAK004718

Am 05/12/2023 um 15:40 schrieb Thomas Wolff via Cygwin:
> Am 05/12/2023 um 14:53 schrieb Corinna Vinschen via Cygwin:
>> On Dec  5 07:36, Thomas Wolff via Cygwin wrote:
>>>
>>> Am 01.12.2023 um 12:02 schrieb Corinna Vinschen via Cygwin:
>>>> On Dec  1 11:22, Cedric Blancher via Cygwin wrote:
>>>>> Not all filesystems have a 128k block/stripe size, and certainly most
>>>>> filesystems have smaller minimum hole sizes than 128k (e.g. 512bytes
>>>>> is common, ref pathconf _PC_MIN_HOLE_SIZE).
>>>> There's no _PC_MIN_HOLE_SIZE in Linux or POSIX.  In Windows, a sparse
>>>> file uses chunks of 64K.  You can see this even with a file of just
>>>> a single block.  Try this:
>>>>
>>>>     $ touch x
>>>>     $ chattr +S x
>>>>
>>>>     $ echo 
>>>> 1234567890123456789012345678901234567890123456789012345678901234567890123456789 
>>>> >> x
>>>>     $ ls -ls x
>>>>     1 -rw-r--r-- 1 corinna vinschen 80 Dec  1 11:56 x
>>>>
>>>>     [repeat echo and ls -ls until...]
>>>>
>>>>     $ echo 
>>>> 1234567890123456789012345678901234567890123456789012345678901234567890123456789 
>>>> >> x
>>>>     $ ls -ls x
>>>>     1 -rw-r--r-- 1 corinna vinschen 720 Dec  1 11:56 x
>>>>     $ echo 
>>>> 1234567890123456789012345678901234567890123456789012345678901234567890123456789 
>>>> >> x
>>>>     $ ls -ls x
>>>>     64 -rw-r--r-- 1 corinna vinschen 800 Dec  1 11:56 x2
>>>>     ^^
>>>>     This
>>> For me, it goes up from 1 to 4, then in steps of 4KB.
>> Is that a local NTFS, did you actually call
>>
>>    chattr +S x
>>
>> after touching the file, and did you check with
>>
>>    lsattr x
>>
>> that x is actually sparse?
> Ups, sorry, I was just throwing my 2p into something. Yes, on a local 
> NTFS; setting chattr +s does not change it but lsattr says:
> ---a-------- .ls-s
>
> So why does chattr not seem to work?
Sorry again, I failed to test properly (I had copied your `chattr +S x` 
which is not the filename I tested... blush).
With chattr +S, I reproduce your observation.

> Thomas
>
>> Corinna
>>
>
>


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

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019