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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 3AD16C43381 for ; Wed, 6 Mar 2019 04:26:10 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C64CB20675 for ; Wed, 6 Mar 2019 04:26:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C64CB20675 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vt.edu Authentication-Results: mail.kernel.org; spf=fail smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.91) (envelope-from ) id 1h1O7R-00006t-Pc; Tue, 05 Mar 2019 23:25:25 -0500 Received: from omr2.cc.ipv6.vt.edu ([2607:b400:92:8400:0:33:fb76:806e] helo=omr2.cc.vt.edu) by shelob.surriel.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91) (envelope-from ) id 1h1O7Q-00006n-98 for kernelnewbies@kernelnewbies.org; Tue, 05 Mar 2019 23:25:24 -0500 Received: from mr4.cc.vt.edu (mr4.cc.ipv6.vt.edu [IPv6:2607:b400:92:8300:0:7b:e2b1:6a29]) by omr2.cc.vt.edu (8.14.4/8.14.4) with ESMTP id x264PNjM005087 for ; Tue, 5 Mar 2019 23:25:23 -0500 Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by mr4.cc.vt.edu (8.14.7/8.14.7) with ESMTP id x264PIFF003640 for ; Tue, 5 Mar 2019 23:25:23 -0500 Received: by mail-qt1-f198.google.com with SMTP id i3so10274938qtc.7 for ; Tue, 05 Mar 2019 20:25:23 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:date:message-id; bh=w7EzCmnXnn1t/Fy2pEL74+6Rm/gbE3PE9lROk6TyoVY=; b=A5lMQnodesKNxDdkeQCBwhNfIlI3QC6VVod6SCFRZEivog6+FB2r8wHdX5L0D8tFVf J2TU5bcq2u0CwPH4d83gnVw8CIBoZcBtgfbvE21OlMLRgfjfIWgB/UU5hWSQaYHSrXQK iIcAwbadmfltxQ/r9jEdeBu/4sKOc1jPzgOWIZs1JOI6HxNi31iTHGn4GwIxc2t2dfEH ab11AtS7mXmNZyIzDnMOsyFv9z+ME9aVGUkOqmYHyT2uCyNnd3WdGWTVkCektXjOr47Y CMPSlByzrdMDIvJsfAARRLfiQmkEvpAzJeHySLv1y2M03oGGU2/Y4DH98I/S8C9XcN9G +9/g== X-Gm-Message-State: APjAAAWDD3AMLwxFu7I8ar0Br50mpvGq9KmBwfYICOp+PZoKvK+2qF2i xD2iPE2G18kL/b7KvL6vjYShKs8XspWFm6OtvfuKlPLEdkBukSlkWofBUc567dKuZu10oJajClo lI3XU/IXIVZVfQBmMXNxJgjcOJvJXSwhchO7nxMs= X-Received: by 2002:a0c:bb98:: with SMTP id i24mr4856156qvg.129.1551846318019; Tue, 05 Mar 2019 20:25:18 -0800 (PST) X-Google-Smtp-Source: APXvYqykOLNQduf25J0kxB5BmOOI1P7ijjyiSNasEfiN+sl1kQr8D9DNsvkpIRIyAln72VIYyf59Uw== X-Received: by 2002:a0c:bb98:: with SMTP id i24mr4856139qvg.129.1551846317772; Tue, 05 Mar 2019 20:25:17 -0800 (PST) Received: from turing-police ([2601:5c0:c001:4341::359]) by smtp.gmail.com with ESMTPSA id a68sm351019qkj.82.2019.03.05.20.25.16 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 05 Mar 2019 20:25:16 -0800 (PST) From: valdis.kletnieks@vt.edu X-Google-Original-From: Valdis.Kletnieks@vt.edu X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: Umair Khan Subject: Re: Unimplemented system call In-reply-to: References: <14930.1551831993@turing-police> Mime-Version: 1.0 Date: Tue, 05 Mar 2019 23:25:15 -0500 Message-ID: <27016.1551846315@turing-police> Cc: Kernel Newbies X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kernelnewbies-bounces@kernelnewbies.org On Tue, 05 Mar 2019 19:52:13 -0500, Umair Khan said: > I was just wondering why are these system calls not implemented? Ah. So now we get to the question you *should* have asked. :) Depends on the system call and the hardware and the kernel config. Often, on embedded systems, you know from the start that your system won't be needed certain optional features, so you can build the kernel without those features to save space. However, if some program tries to issue a syscall that's related to those optional features, you have to return *some* sort of error. So 'not implemented' it is _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies