From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.17.24]) by sourceware.org (Postfix) with ESMTPS id BA7C93858426 for ; Tue, 5 Dec 2023 14:48:04 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org BA7C93858426 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=towo.net Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=towo.net ARC-Filter: OpenARC Filter v1.0.0 sourceware.org BA7C93858426 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=212.227.17.24 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 Received: from [192.168.178.51] ([91.65.216.118]) by mrelayeu.kundenserver.de (mreue107 [212.227.15.183]) with ESMTPSA (Nemesis) id 1MBV2f-1qxZDI2Dnj-00Cwdi for ; Tue, 05 Dec 2023 15:48:03 +0100 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@cygwin.com References: <33d4b0df-7a6a-40cf-85a2-9a4300198672@towo.net> <12e1d9d9-bc56-456e-a1ab-c760987f3ac2@towo.net> From: Thomas Wolff Autocrypt: addr=towo@towo.net; keydata= xsDNBGNaf3QBDACVevqudcTSevLThXKQPU1QpaDxtGuYjtwmr7i9wXxVGih4Y4oxOJN4PYlu KBX9IVAI4651dA+xYtXuyIkWOPZWyyzkGKavQOn3Q7dk09oj7bh2IwOndpxXXde337D408EQ bQEGbMHr9lOWhSAideowzgCeFIvGTf2AovbPh97HpexJn1/HCRiRAhTNlrkS1DByUgCAeEMK fEr6aGM/Ou29MT+eTnQwOIZTnl9Z9LxM2FtqqMH3MycC7I2OoW3XXhuL8BPQdyJUjWa0/J11 Oo5jFkRXtWenIns6jGn18oW72jnDmo9jXwwS+iZWAV6Y51nhD7jSC+3xs9ORmPCdtHUSpTr1 zh67UueUJ3DUUNVuA25Hn/9EJMJ2L60BGUEr88NEB6pcZhmcwdkurAQeYT6t+frzBz2ctsoN BoxP/Xc02yd+z7hXWRRMrJWh9WHlQHA3Z4FfmyNhyPhs3MgKTJ1E9QfzGquigAmF3/k/Dc1m 7cSOKhGYhpEJdSpdXccJFKkAEQEAAc0cVGhvbWFzIFdvbGZmIDx0b3dvQHRvd28ubmV0PsLB BwQTAQgAMRYhBHUiRKsHn5d8BpWdP8bz0e72Bp0CBQJjWn93AhsDBAsJCAcFFQgJCgsFFgID AQAACgkQxvPR7vYGnQKSMAv8Di+8MXB2mcfsemRdShfLLKcLOv+d0CXAtPVaY3XKxbKpRvC9 +AAT5wIHYjQft77/b2y87vGIh+nQ5hKLtNtQPSDtqG/Igkb5jAXpLi28fSUzgM96DvARmwve 5wSnAU3prxH+Y63YpOpslEcGMRoEtYCDy1ANMYPcEZT/YvDd4CplyyEai4VYrw3/LsESDYlY GK6uMQzZ1jl2cNOUFu6BwLUeZIcwaqGto8n4R4nbf4jxUEpa21bWBPqE+Jf49uipjPr/iJ72 5HbdWuuCfyTTJEJjfNEBigWP2RXM9iNDcO61V3aEjh76tThfBK2MMlLWfZkQaQziu24x8R4B I0efJYWBX2Sv2qnsH/EWj7FUIZjRqGG7LnWHLShfG6yjSOTOWYi8BbsvoftpaLWgZX28aGX4 uzuSZ5L0caXh/pr/gSgqoH/YbuFIgqtQH4seOBgTybd22Vpe78rnc+8450pN8qwchHAZaJka UxS0SpYxXzXmHUKILA4C43s0U/z2Mez9zsDNBGNaf3cBDADeJ7paMrb6f1+k8wM7tyk0/Ded KX/pOejt/D20Ceerw2iL/4tUmBL+A3ic2yjiSFUSsEfHwgCVwKrn4MwZtkesdiphm2lk6xWc k1ENCQy44QwQT6UZ/mHWYWcj5LS6ua183x1zdn9iF3lv150nm/ssw56D7USz/ap1Vh0lf5te D+CIheGLocVDqxWiu7rHP8jKRWFgq/+OU6HKX8p2Yv1oYsykh9qF2bFzawLDS+S1VbfRicfD G0RtceL/BAf7b6UE5u9TGdfrFEa2TKZeS/FS/ViKUfwsXQIki1sWt2FQENbuDY28vxyR46ZZ 0gixDCFUoBw5pkmOGVQa+1RQYrRqlN4X0CAgp7mFVeEHl5NTgiL1bemkQVmHOUDG+CzNg+Lk UGoedAtT672l3JjrnSs4j8zNshpgV2OfAhAC+V9XvqCjMnxzVfXkVlbuWpPfUWQeFclLGg8P agpQUE0Ux+VV4DoeQCxYEnRCf/n7n+IRfILj5+2l6Zw4M7zSu6ii0tUAEQEAAcLA9gQYAQgA IBYhBHUiRKsHn5d8BpWdP8bz0e72Bp0CBQJjWn97AhsMAAoJEMbz0e72Bp0CQr4L/REdT0SF mbapnZIe92THCdtAUgwEv8VdNiNFBJelz8P/fuXuNPtisYvQQD4e64zpWe2UC4Cxo9DUk/pW 6Qci1xaXRKEiSPjHdSGGVB1PFIcqiS75GCf/ga/Dnfsy0Y4Uh6OGTQnkvZLBCe3vvcVLDQ7F PuV79zA9/eOeOW6aGoO6bq/wH+z96f9LyTITkQDy07fm6JYTGuzAoJE2AEboU1mgbtlx+tAa QFkpAQkp2g1Vhc3A7k4vntlHOrjMC+uVFh7QTGFfIlLRF6izUjSe6EZ06LErzlIiE05RP3yF FSRWidW0wze26peYlxYVgH1+T9wMTW2oiTBybfAMHBAxUP7Gr1WUo/oJEr0srWhatz8AwydP y7NwFbdpYn0NcFBaIlLW/JL11Eovwlivow+oGpzGFuuzSuflp2q9s2JWtn4EhW0kEs93D0LP iuJWvRaCZ6aD3uF3FMW8wyVWZYsLrzune2jH8w/uKMprDEOGOm+BcyhEFedTyY1ygbZKl+0G kQ== In-Reply-To: <12e1d9d9-bc56-456e-a1ab-c760987f3ac2@towo.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 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 YWuFNe1olgFudElguo4MsdveR3vN9IosZwa7GlTjifzgBeHEbD+PEhYe3NoiX3pBxQpTifUcw gfaJv2Xjw4qsvu0y5Eu1gcXa2SQnvSTE99bKCr0xXyK8N5YWQJItBesvdyfXaidjZo6Mgst0z JnLiU2xFoLUFQvR61dH+Y4xT4tumCkMB9XV1WmsuwQP962HFPXcK+qofy8Cgaz8+sIRb0soeD bxP4DDovFsFptQCaumvAEOk4jlxJ9hPF0pX95emB1SwAlQbSv2VSk4SZp84JsWMsr7hVH6zde pPIojYXhT4PXk7ZTMuwk2JMVTWOSUrh77B85EvheydHAaLg0P8DrsqP1MvvlSwJwKQrLlk737 6hOimPmnMAx/t+ZMI7QMS5eeWp6pu00Df8j8X7PSDLDx5I8Tqvi25rHdrtdOmQPtxA5o0j3Kf oivzC0rxVBxE3fC95hRxF/JGB0tuJHU44K+DDIJNRdDXsZwihJ3RqLWsKgS7tHAHLlFnvmLBL uGsXAWVz2P9NFBnQqjCvyCmciOmYgkKa1sxI8IciUbGHWULWlb6+dpMjTFFglUCsGTA6MqNUA EifhPfQlYtULvQw8s7o6mGhKEQ1Ii+/JlFbafXzQpi1Efk/LjbXS9EhjxS/O62WpIRr9juQlJ ouRtnd7oBU8iYDINMimtwlYIUWgiHoAqW+UzTMlk4pqZxkCAEi8AOckCHT7fJQJXtIyKeDlgY NNajP4pbz9wGIp9u0KnMxcTnvlkHZAfv9JX3nXqcs0FT3BO/zgNLqqaMRXU4SpWwQvBaB0Exa p4o8CkJFPYwLHaj8V1ot1Cf3sLD2S1Ftcl5RdQog1O50mL/kqD6OQ6s3d6By/KXotjsOO/0qN kjzDKshfb5nRIJQ== 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 List-Id: 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 >> > >