From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A35B5C4363C for ; Fri, 2 Oct 2020 16:53:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75BDE20719 for ; Fri, 2 Oct 2020 16:53:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725995AbgJBQx1 (ORCPT ); Fri, 2 Oct 2020 12:53:27 -0400 Received: from zimbra.cs.ucla.edu ([131.179.128.68]:47150 "EHLO zimbra.cs.ucla.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725991AbgJBQx1 (ORCPT ); Fri, 2 Oct 2020 12:53:27 -0400 Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 6C874160052; Fri, 2 Oct 2020 09:53:26 -0700 (PDT) Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id IzUKaIsyecQU; Fri, 2 Oct 2020 09:53:25 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id AA237160065; Fri, 2 Oct 2020 09:53:25 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 8rffufaipKAM; Fri, 2 Oct 2020 09:53:25 -0700 (PDT) Received: from [192.168.1.9] (cpe-23-243-218-95.socal.res.rr.com [23.243.218.95]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 439C2160052; Fri, 2 Oct 2020 09:53:25 -0700 (PDT) Subject: Re: [PATCH v4 1/2] system_data_types.7: Add 'void *' To: Alejandro Colomar Cc: mtk.manpages@gmail.com, linux-man@vger.kernel.org, gcc-patches@gcc.gnu.org, libc-alpha@sourceware.org, linux-kernel@vger.kernel.org, jwakely.gcc@gmail.com, David.Laight@ACULAB.COM References: <20201002121645.23646-1-colomar.6.4.3@gmail.com> <20201002151419.32053-2-colomar.6.4.3@gmail.com> From: Paul Eggert Autocrypt: addr=eggert@cs.ucla.edu; 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201002151419.32053-2-colomar.6.4.3@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org On 10/2/20 8:14 AM, Alejandro Colomar wrote: > +.I void * GNU style is a space between "void" and "*", so this should be '.I "void\ *"', both here and elsewhere. The backslash prevents a line break. > +Conversions from and to any other pointer type are done implicitly, > +not requiring casts at all. > +Note that this feature prevents any kind of type checking: > +the programmer should be careful not to cast a Change "cast" to "convert", since the point is that no cast is needed. > +.PP > +The conversion specifier for > +.I void * > +for the > +.BR printf (3) > +and the > +.BR scanf (3) > +families of functions is > +.BR p ; > +resulting commonly in > +.B %p > +for printing > +.I void * > +values. %p works with any object pointer type (or in POSIX, any pointer type), not just void *. Should also mention "void const *", "void volatile *", etc. Plus it really should talk about plain "void", saying that it's a placeholder as a return value for functions, for casting away values, and as a keyword in C11 for functions with no parameters (though this is being changed in the next C version!). I sent comments about most of this stuff already.