From owner-freebsd-hackers@freebsd.org Thu Jan 7 15:27:58 2016 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 59222A66544 for ; Thu, 7 Jan 2016 15:27:58 +0000 (UTC) (envelope-from mmatalka@gmail.com) Received: from mail-wm0-x22d.google.com (mail-wm0-x22d.google.com [IPv6:2a00:1450:400c:c09::22d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 034C4175D for ; Thu, 7 Jan 2016 15:27:58 +0000 (UTC) (envelope-from mmatalka@gmail.com) Received: by mail-wm0-x22d.google.com with SMTP id f206so102169755wmf.0 for ; Thu, 07 Jan 2016 07:27:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=7/E040bytIFkAgrO0D35GvHfSnUY2W7ZR095cjO4R4c=; b=fG6mHvvwrOrSb5DyDIdU4iAXy5kSarw1CGdRI4xK9RU8wssief4YMn2bBjaZoavpTv CS5RHBm1jgkz1OqzCa4v/+/EM5pxUX7i1DaNUeQjenpODI2DH+2BvAWVwGHiVwyJ9EDh 9qrwJjfEvqj0WwPjqlbBTdibq+ackZj4xnh0cVIjVX0rYjM6lLlAfGsITcoXWcZnQbDq yWS5sAxK5KJe35wK//zJr32/TpW72d8kc80BKO/15AD7yPvTai/5wY8hLfsXxm7SnBzu 5/yYhRVXTeIoo4HT9lPLqorQdtpI2Cu8u0wpoUQzWaMtXbdqBJBVPithFCjaucJRKIKh +pBg== MIME-Version: 1.0 X-Received: by 10.28.153.148 with SMTP id b142mr18292412wme.5.1452180476600; Thu, 07 Jan 2016 07:27:56 -0800 (PST) Received: by 10.28.154.2 with HTTP; Thu, 7 Jan 2016 07:27:56 -0800 (PST) Received: by 10.28.154.2 with HTTP; Thu, 7 Jan 2016 07:27:56 -0800 (PST) In-Reply-To: <86ziwho1jg.fsf@gmail.com> References: <86ziwho1jg.fsf@gmail.com> Date: Thu, 7 Jan 2016 16:27:56 +0100 Message-ID: Subject: Re: Can PIPE_BUF be increased? From: Malcolm Matalka To: freebsd-hackers@freebsd.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.20 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 Jan 2016 15:27:58 -0000 Den 7 jan 2016 4:24 em skrev "Malcolm Matalka" : > > As far as I can tell, PIPE_BUF is 512 bytes by default. Using getconf > and looking at the header files /usr/include. I'm writing a program > that would benefit from a larger PIPE_BUF, is it possible to change this > value? It looks like Linux and OS X have a higher default and OS X will > do some magic to increase the size if necessary. I haven't found > anything indicating the same in FreeBSD. > I realized I might not be clear enough here: I'm trying to increase the number if bytes i can write to a pipe atomically. > Thanks, > /Malcolm >