From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: ludo@gnu.org (Ludovic =?iso-8859-1?Q?Court=E8s?=) Newsgroups: gmane.lisp.guile.user Subject: Re: Leap second bug? Date: Mon, 09 Jun 2008 00:00:44 +0200 Message-ID: <874p8337ub.fsf@gnu.org> References: <20080607204054.GA7677@localhost.localdomain> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1212962483 11318 80.91.229.12 (8 Jun 2008 22:01:23 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 8 Jun 2008 22:01:23 +0000 (UTC) To: guile-user@gnu.org Original-X-From: guile-user-bounces+guile-user=m.gmane.org@gnu.org Mon Jun 09 00:02:04 2008 Return-path: Envelope-to: guile-user@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1K5Sxc-0005ZZ-MD for guile-user@m.gmane.org; Mon, 09 Jun 2008 00:02:00 +0200 Original-Received: from localhost ([127.0.0.1]:46027 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1K5Swp-0002jL-LE for guile-user@m.gmane.org; Sun, 08 Jun 2008 18:01:11 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1K5Swk-0002is-NI for guile-user@gnu.org; Sun, 08 Jun 2008 18:01:06 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1K5Swj-0002ic-7f for guile-user@gnu.org; Sun, 08 Jun 2008 18:01:06 -0400 Original-Received: from [199.232.76.173] (port=56892 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1K5Swj-0002iZ-1N for guile-user@gnu.org; Sun, 08 Jun 2008 18:01:05 -0400 Original-Received: from main.gmane.org ([80.91.229.2]:43711 helo=ciao.gmane.org) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1K5Swj-0000fO-4s for guile-user@gnu.org; Sun, 08 Jun 2008 18:01:05 -0400 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1K5SwZ-0006nS-Vu for guile-user@gnu.org; Sun, 08 Jun 2008 22:00:56 +0000 Original-Received: from reverse-83.fdn.fr ([80.67.176.83]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 08 Jun 2008 22:00:55 +0000 Original-Received: from ludo by reverse-83.fdn.fr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 08 Jun 2008 22:00:55 +0000 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 28 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: reverse-83.fdn.fr X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 21 Prairial an 216 de la =?iso-8859-1?Q?R=E9volution?= X-PGP-Key-ID: 0xEA52ECF4 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 821D 815D 902A 7EAB 5CEE D120 7FBA 3D4F EB1F 5364 X-OS: i686-pc-linux-gnu User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.1 (gnu/linux) Cancel-Lock: sha1:0I3e1mYm7a+APxAAx5+/morPwdE= X-detected-kernel: by monty-python.gnu.org: Linux 2.6, seldom 2.4 (older, 4) X-BeenThere: guile-user@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: General Guile related discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-user-bounces+guile-user=m.gmane.org@gnu.org Errors-To: guile-user-bounces+guile-user=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.user:6605 Archived-At: Hi, Ondrej Zajicek writes: > (use-modules (srfi srfi-19)) > (define (str->date str) (string->date str "~d-~m-~Y")) > (define (date->str str) (date->string str "~d-~m-~Y")) > > (date->str (time-utc->date (date->time-utc (str->date "01-01-2006")))) > -> "31-12-2005" > > Is is a bug in leap second handling or is it a expected behavior? Not sure. Our leap second table is up-to-date. Apparently, `time-utc->date' honors leap seconds, while `date->time-utc' doesn't. In the reference implementation at schemers.org (upon which Guile's is based), none of these two honors leap seconds AFAICS. I'm no expert in that area but I would suggest emailing the SRFI-19 mailing list [0] for advice. It seems that most implementations use the reference implementation with few modifications, in which case most implementations might be affected. Did you try it with other Scheme implementations? Thanks, Ludovic. [0] http://srfi.schemers.org/srfi-19/