From owner-freebsd-hackers@FreeBSD.ORG Fri Jan 2 02:11:54 2009 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 103DB106564A for ; Fri, 2 Jan 2009 02:11:54 +0000 (UTC) (envelope-from freebsd@bitfreak.org) Received: from srv.twinthornes.com (srv.twinthornes.com [65.75.198.146]) by mx1.freebsd.org (Postfix) with ESMTP id E27C38FC18 for ; Fri, 2 Jan 2009 02:11:53 +0000 (UTC) (envelope-from freebsd@bitfreak.org) Received: from [10.9.70.104] (c-76-27-226-62.hsd1.or.comcast.net [76.27.226.62]) by srv.twinthornes.com (Postfix) with ESMTPSA id B352924C6C for ; Thu, 1 Jan 2009 17:55:43 -0800 (PST) Message-ID: <495D7421.1090208@bitfreak.org> Date: Thu, 01 Jan 2009 17:55:45 -0800 From: Darren Pilgrim User-Agent: Thunderbird 2.0.0.19 (Windows/20081209) MIME-Version: 1.0 To: freebsd-hackers@freebsd.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Is the FreeBSD clock UTC or TAI? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Jan 2009 02:11:54 -0000 This came up during discussion of leap seconds and why UTC and TAI are different. My question is, does FreeBSD's internal clock use UTC or TAI for timekeeping? That is, is wallclock calculated from an exact count of the number of seconds since epoch (TAI), then adjusted with a leap seconds table to match UTC, or does it internally use UTC and have code to deal with the ambiguous seconds that occur at each leap second?