From owner-svn-src-all@freebsd.org Wed Sep 11 19:48:33 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 37D95DE5F2; Wed, 11 Sep 2019 19:48:33 +0000 (UTC) (envelope-from asomers@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 46TCBT0hkKz4M74; Wed, 11 Sep 2019 19:48:33 +0000 (UTC) (envelope-from asomers@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id EFCD3B65D; Wed, 11 Sep 2019 19:48:32 +0000 (UTC) (envelope-from asomers@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x8BJmWEW092484; Wed, 11 Sep 2019 19:48:32 GMT (envelope-from asomers@FreeBSD.org) Received: (from asomers@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x8BJmWZn092483; Wed, 11 Sep 2019 19:48:32 GMT (envelope-from asomers@FreeBSD.org) Message-Id: <201909111948.x8BJmWZn092483@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: asomers set sender to asomers@FreeBSD.org using -f From: Alan Somers Date: Wed, 11 Sep 2019 19:48:32 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r352231 - head/lib/libc/sys X-SVN-Group: head X-SVN-Commit-Author: asomers X-SVN-Commit-Paths: head/lib/libc/sys X-SVN-Commit-Revision: 352231 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Sep 2019 19:48:33 -0000 Author: asomers Date: Wed Sep 11 19:48:32 2019 New Revision: 352231 URL: https://svnweb.freebsd.org/changeset/base/352231 Log: getsockopt.2: clarify that SO_TIMESTAMP is not 100% reliable When SO_TIMESTAMP is set, the kernel will attempt to attach a timestamp as ancillary data to each IP datagram that is received on the socket. However, it may fail, for example due to insufficient memory. In that case the packet will still be received but not timestamp will be attached. Reviewed by: kib MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D21607 Modified: head/lib/libc/sys/getsockopt.2 Modified: head/lib/libc/sys/getsockopt.2 ============================================================================== --- head/lib/libc/sys/getsockopt.2 Wed Sep 11 19:29:40 2019 (r352230) +++ head/lib/libc/sys/getsockopt.2 Wed Sep 11 19:48:32 2019 (r352231) @@ -28,7 +28,7 @@ .\" @(#)getsockopt.2 8.4 (Berkeley) 5/2/95 .\" $FreeBSD$ .\" -.Dd February 10, 2019 +.Dd September 11, 2019 .Dt GETSOCKOPT 2 .Os .Sh NAME @@ -431,7 +431,8 @@ option is enabled on a .Dv SOCK_DGRAM socket, the .Xr recvmsg 2 -call will return a timestamp corresponding to when the datagram was received. +call may return a timestamp corresponding to when the datagram was received. +However, it may not, for example due to a resource shortage. The .Va msg_control field in the