From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/9269 Path: news.gmane.org!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: Fwd: [Rd] [musl] strptime() question Date: Thu, 4 Feb 2016 16:32:49 -0500 Message-ID: <20160204213249.GT9349@brightrain.aerifal.cx> References: <20160204160708.GP9349@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1454621597 13845 80.91.229.3 (4 Feb 2016 21:33:17 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 4 Feb 2016 21:33:17 +0000 (UTC) Cc: r-devel , musl@lists.openwall.com To: Alba Pompeo Original-X-From: musl-return-9282-gllmg-musl=m.gmane.org@lists.openwall.com Thu Feb 04 22:33:15 2016 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1aRRWZ-0002Ze-3T for gllmg-musl@m.gmane.org; Thu, 04 Feb 2016 22:33:11 +0100 Original-Received: (qmail 1417 invoked by uid 550); 4 Feb 2016 21:33:09 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Original-Received: (qmail 1399 invoked from network); 4 Feb 2016 21:33:08 -0000 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:9269 Archived-At: On Thu, Feb 04, 2016 at 04:35:22PM -0200, Alba Pompeo wrote: > I forwarded our talk on musl mailing list to R mailing list. > I got this response. > Does it help? > Also, what do you think about making a new email that's sent to both > musl and R mailing list, that way devs from both projects can > communicate? It's a tad inefficient for me to keep forwarding messages > like this back and forth. I'm cc'ing both lists now. > ---------- Forwarded message ---------- > From: Simon Urbanek > Date: Thu, Feb 4, 2016 at 3:01 PM > Subject: Re: [Rd] [musl] strptime() question > To: Alba Pompeo > Cc: r-devel > > > > On Feb 4, 2016, at 11:20 AM, Alba Pompeo wrote: > > > There is incompatibility between R strptime and musl libc. I posted > > about it on their mailing list, but they need more information I can't > > provide, so I'm forwarding the message here in hope R developers can > > help. Thanks. > > Generally, it's using the standard tzset() call to set the time zone > http://pubs.opengroup.org/onlinepubs/009695399/functions/tzset.html The tzset function doesn't really do much interesting; it just updates some global state to match the current value of the TZ environment variable, but most time.h functions do this already anyway. Anyway this doesn't really answer the question of what R's strptime function is doing to add timezone functionality onto the underlying system's strptime. Is R changing the environment (this is highly unsafe in any potentially-multithreaded process, BTW)? Is it using the globals set by tzset to compute adjustments to the result? Rich