220 33753 article Path: news.gmane.org!.POSTED!not-for-mail From: "'Jeffrey Yasskin' via ISO C++ Standard - Future Proposals" Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: string_view for fstream::open() Date: Wed, 9 Aug 2017 16:21:37 -0700 Lines: 27 Approved: news@gmane.org Message-ID: References: <9fedbad3-c6f6-4dbe-a215-814666c52c6b@isocpp.org> <1894906.unAOSKiKQz@tjmaciei-mobl1> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1502320929 6315 195.159.176.226 (9 Aug 2017 23:22:09 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 9 Aug 2017 23:22:09 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDDM34EO6QDRBF5SV3GAKGQER4BRUMA@isocpp.org Thu Aug 10 01:21:56 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wm0-f69.google.com ([74.125.82.69]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dfaIU-0000x5-RK for gclcip-std-proposals@m.gmane.org; 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[2a00:1450:400c:c09::22f]) by mx.google.com with ESMTPS id r37si5197468edd.185.2017.08.09.16.21.59 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Aug 2017 16:21:59 -0700 (PDT) Received-SPF: pass (google.com: domain of jyasskin@google.com designates 2a00:1450:400c:c09::22f as permitted sender) client-ip=2a00:1450:400c:c09::22f; Original-Received: by mail-wm0-x22f.google.com with SMTP id f15so8489113wmg.1 for ; Wed, 09 Aug 2017 16:21:59 -0700 (PDT) X-Received: by 10.28.221.137 with SMTP id u131mr6251435wmg.19.1502320918706; Wed, 09 Aug 2017 16:21:58 -0700 (PDT) Original-Received: by 10.28.216.144 with HTTP; Wed, 9 Aug 2017 16:21:37 -0700 (PDT) In-Reply-To: <1894906.unAOSKiKQz@tjmaciei-mobl1> X-Original-Sender: jyasskin@google.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=RncPVkOJ; spf=pass (google.com: domain of jyasskin@google.com designates 2a00:1450:400c:c09::22f as permitted sender) smtp.mailfrom=jyasskin@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com X-Original-From: Jeffrey Yasskin Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:33753 Archived-At: On Wed, Aug 9, 2017 at 12:49 PM, Thiago Macieira wrote: > On quarta-feira, 9 de agosto de 2017 09:15:59 PDT 'Jeffrey Yasskin' via ISO C+ > + Standard - Future Proposals wrote: >> However, being system calls, they also cost significantly more than >> the cost of copying a path-length string, so don't be too afraid of >> just doing that. > > The problem is the copying an input of arbitrary length in an exception-free > and thread-safe manner. > > You can't do malloc(), since that might fail. You can't use new[] because it > might throw. You can't lock a mutex because that is not async signal safe. Which are the low-level APIs that take null-terminated strings and are also async-signal-safe and failure-free? (If I needed exception-freedom I'd use new(nothrow) or catch the exception and turn it into a failure.) Thanks, Jeffrey -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/CANh-dXn0iLxgvBbUFH0UrBM7jdumO_aPX%3DY1YxHAMdoBPrS7Cw%40mail.gmail.com. .