DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org BE6453858C53
To: Ken Brown <kbrown AT cornell DOT edu>, "cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Subject: RE: [EXTERNAL] Re: Weird issue with file permissions
Thread-Topic: [EXTERNAL] Re: Weird issue with file permissions
Thread-Index: AdiOLwn0C+4yq9lkQ4mvvv+7h9C3VQAFDzmAAAG+/VA=
Date: Sat, 2 Jul 2022 19:37:05 +0000
Message-ID: <DM8PR09MB7095B72B7F58F581D3A21B97A5BC9@DM8PR09MB7095.namprd09.prod.outlook.com>
References: <DM8PR09MB7095CE12D39F3F81CBB15536A5BC9 AT DM8PR09MB7095 DOT namprd09 DOT prod DOT outlook DOT com>
 <9e2a5f6a-b0cb-f7b5-a250-a6030ef24f09 AT cornell DOT edu>
In-Reply-To: <9e2a5f6a-b0cb-f7b5-a250-a6030ef24f09@cornell.edu>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?gChpjqGee2t/YYA7+HZ1nekc+CR4qP0y1tE0a8gtmvd4Kz8WbhYFHPXBcn1/?=
 =?us-ascii?Q?xKZQNQ+eA/twp2bUx8Hn5JGrySnzP4A1SN/RsK8LzD9txlqa1+bGbvT3x0Uy?=
 =?us-ascii?Q?ZGopnlUbinzMTwnrZ2FdLn6CQjAHxfgZORBbMKtehhlj0VjuSFKsnI9+IK5T?=
 =?us-ascii?Q?TVuoLWqvmOh5Ts4R40LOhmNwG1+9DG2aocPvZweqYYJR90BkTIwgsE0j6bsR?=
 =?us-ascii?Q?wvE2rlnQNLnV22pLYM5Jisdu0/glp0+b5dWzR5uMM/Y2RuCi7F5RMi5KoX/5?=
 =?us-ascii?Q?eZea84ayzD2mMgkkf18/Z2QIPzz+i8bKd6Tdw6MpBhNCOlUevdY7mIXMgals?=
 =?us-ascii?Q?MbCXOM48PirpDp54G1hw3thNs7idtMIAteEsUnSPdQbViVYqBl95vthYSvhs?=
 =?us-ascii?Q?/Q/5MQKfRuXUp/KwjuwdqGpI2LTLApaskq0wlgNNK6T7TRbAXrnsZUllsIlE?=
 =?us-ascii?Q?mgi+CKnUr3XHICDOJM/8KNTHKG+YVBwTAA5dC1bq8fwASVa3lw3HW1CXUCtg?=
 =?us-ascii?Q?KNG0r+uPB335GDmPyvfZwLfmbL93Yli7KjgokIWbRuZMj7HxkjTO/XnKifno?=
 =?us-ascii?Q?OVTLNbFST2m6uzq8+RGohXhN49eJhZqF/QfKWT7FbSOXbNgySwyjbIE+Rt7g?=
 =?us-ascii?Q?LQngcs/U3L7LhNtVGG0JICE6sL8+ihIPBwBYX0ZZ4NTVMavVVUmGl6NSu8rJ?=
 =?us-ascii?Q?kdcmbmZjgdHhPPtBLvJmJ0n61RaRYIMszQr0BGRZr2obRSSbYUR+svkkMvHy?=
 =?us-ascii?Q?iNh+2wRzoZQPYBnzFB9BaSd3QRaR/wSL395pY7gohVHn7v24zh41b9QfOKhb?=
 =?us-ascii?Q?QtLU59U/urDqwF9D5Wc9f8Tlne4WsAjKWm/uGzOz+4J1NHVUmF0kd3VjD0WG?=
 =?us-ascii?Q?IboPxKIMgUBbM6Rhk5NDnbiFgCTQ+9UfDkJZgEXpu5uzdOqQXNqIoLV2I6Dh?=
 =?us-ascii?Q?0eFfGILAvk/Nu6BIRBS/yw5Ko/TFpqvhuAE1I0c3FSRI7hi3DRLdCeeDvWET?=
 =?us-ascii?Q?GNr/1834IWEstvNFAJDmv+XcSmdl+qrbMhtMtsYNzmnoF53KRXnhX37mZxS7?=
 =?us-ascii?Q?kfEf3wjBzns7IDghD/H6XKnVGESETJ8JsQ1rGPKAlrC8UeCKh7mYTzOe5shG?=
 =?us-ascii?Q?jVfTQXKIsZxUXhxlt/y0lqFPebq07AckhKZkT7wP0xFAdbiJSAHwD3vtRPWx?=
 =?us-ascii?Q?xblESrruUiWVlmiduBIEwFxTd2artaEow5Yt8YdETdHb0Yfj+gSdfDQBbiFP?=
 =?us-ascii?Q?SL3tTLoeYEo2l/qXJZgUVfkgutmmKQLEtN1TUF8DWH9Uxr3hfFWGDaFHKUL2?=
 =?us-ascii?Q?KU76Dp2/wVpcajpGYDhP+oDxyJNT2THCasYLfaoMkCG6g0ARdpd9ooBYccaw?=
 =?us-ascii?Q?N9Ncgp3AcWcJag7lXuadMZh0PDQAuQz9OaVkuVh6si2b1bBkMP0gHRZSID44?=
 =?us-ascii?Q?c2loQudzv476nBgR+ShHp+XlSQZSXvNmyoqs5Fj3GB0ywvxdp8zeQfEB7Vac?=
 =?us-ascii?Q?tY56Ai1sbFHsqgGzPzNOrYlmX2+/pAGeFscR8XDttGZ+bQ+mF+J7StDEuBd9?=
 =?us-ascii?Q?XPNOqSnmKpWS3FtJiU0=3D?=
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: DM8PR09MB7095.namprd09.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 12c4bb59-f601-471a-a1fd-08da5c623eda
X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Jul 2022 19:37:05.6787 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 14b77578-9773-42d5-8507-251ca2dc2b06
X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR09MB8169
X-OriginatorOrg: ncbi.nlm.nih.gov
X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00, DKIM_SIGNED,
 DKIM_VALID, DKIM_VALID_EF, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE,
 T_SPF_HELO_PERMERROR 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: 2.1.29
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
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: "Lavrentiev, Anton \(NIH/NLM/NCBI\) \[C\] via Cygwin" <cygwin AT cygwin DOT com>
Reply-To: "Lavrentiev, Anton \(NIH/NLM/NCBI\) \[C\]" <lavr AT ncbi DOT nlm DOT nih DOT gov>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: "Cygwin" <cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com>

> what your test program was actually doing.  But you seem to be assuming that
> calling fchmod on a socket descriptor should affect the permissions on the
> socket file (assuming the socket is bound).  Is that documented anywhere?  POSIX
> says that the behavior of fchmod on a socket descriptor is unspecified

The socket file descriptor for a bound UNIX sockets refers to an object in a filesystem
(it's practically a file), which the bind() system call creates.  The access to the socket
is controlled by the permission bits, when someone actually tries to connect to it,
so permissions should be working for these objects (otherwise, there's no other way!)

And fchmod() for a bound Unix socket works on Linux and many other Unix flavors, actually.

Anton Lavrentiev
Contractor NIH/NLM/NCBI

-- 
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