From owner-freebsd-hackers@FreeBSD.ORG Fri May 24 19:12:07 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id F08C320B for ; Fri, 24 May 2013 19:12:07 +0000 (UTC) (envelope-from otacilio.neto@bsd.com.br) Received: from mail-yh0-x230.google.com (mail-yh0-x230.google.com [IPv6:2607:f8b0:4002:c01::230]) by mx1.freebsd.org (Postfix) with ESMTP id AEDB9A86 for ; Fri, 24 May 2013 19:12:07 +0000 (UTC) Received: by mail-yh0-f48.google.com with SMTP id f35so384351yha.35 for ; Fri, 24 May 2013 12:12:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsd.com.br; s=capeta; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; bh=xv+LKnGGUTApj0RskmAd6pIDHIwlH/X1TKtLPUu2zP4=; b=cmp8VOOTbIZ0tM4U7pgVGqdqGSn4fMyCIvzThrLo3PVXnnipA6k6ha3151INKc6I0p huNCiSyRrSRhvvSGfMX3w3Tdyn1gfV6lDtSlaYG0Mamuzhm6pZnlfzMY9LTb4VPMCwWR P1qgAMwyAsckrSgMC6WzPUpwn2iewIqV0nIVc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:x-enigmail-version:content-type :content-transfer-encoding:x-gm-message-state; bh=xv+LKnGGUTApj0RskmAd6pIDHIwlH/X1TKtLPUu2zP4=; b=ZBek+MMcVFnYEt36T4L6OXJ8m1xNd+Qx4NfQr3kUb/VcDNP7TZTWv0AVefadeZGtZU U4x25unBYzdGzPQDxuSKE6qeleZxxOh785laC/shv+IsYXuQPgjyHyOloMbXFG3A9aaU ziqakTiic+LC99ogJl1xGkbVNZOIbAxVt8rOhkRJkELZTVyVlNCdSmIxRpHhsgAOCdgT 35QLa4634mhYQAbFUPLkRa3ogHANhsuNWKz9vDh4iPyO7RLzlPcTULFjRXdZztO33LWM /omsaFddD3NssNIFlOp2RP8mPj5lcunhPraM/aeetUuJx/ZQLYh67SZb5QkiFDED6lDP Auig== X-Received: by 10.236.123.100 with SMTP id u64mr10425221yhh.4.1369422727016; Fri, 24 May 2013 12:12:07 -0700 (PDT) Received: from [192.168.2.101] ([187.114.197.44]) by mx.google.com with ESMTPSA id m74sm25405323yhm.0.2013.05.24.12.12.03 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 24 May 2013 12:12:06 -0700 (PDT) Message-ID: <519FBB7E.2060804@bsd.com.br> Date: Fri, 24 May 2013 16:11:58 -0300 From: =?windows-1252?Q?Otac=EDlio?= User-Agent: Mozilla/5.0 (X11; FreeBSD i386; rv:17.0) Gecko/20130406 Thunderbird/17.0.5 MIME-Version: 1.0 To: freebsd-hackers@freebsd.org Subject: Re: Writing a (BSD like) Operating Systems From Scratch References: Your message "Fri, 24 May 2013 10:15:23 -0000." <8F56C8EF8265DF489B64A19B10910AC7025C53B2@ex10-mbx-14001.ant.amazon.com> <201305241340.r4ODcju4009740@fire.js.berklix.net> <8F56C8EF8265DF489B64A19B10910AC7025DF4B3@ex10-mbx-14001.ant.amazon.com> <519FB557.1010403@peterschmitt.fr> In-Reply-To: <519FB557.1010403@peterschmitt.fr> X-Enigmail-Version: 1.5.1 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Gm-Message-State: ALoCoQmFxTOzOc3a+tnH1s+Cp18YhafOVzGSSbDZbrMmAzFuQUgqRF1OxiYEcSlD+/k0KNYIXnUd X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 May 2013 19:12:08 -0000 On 24/05/2013 15:45, Florent Peterschmitt wrote: > Le 24/05/2013 18:57, Welcome, Traiano a écrit : >> Hi Julian >> >> Thanks, any response is appreciated, here's mine: >> >> >>> -----Original Message----- >>> From: owner-freebsd-hackers@freebsd.org [mailto:owner-freebsd- >>> hackers@freebsd.org] On Behalf Of Julian H. Stacey >>> Sent: 24 May 2013 15:39 >>> To: Welcome, Traiano >>> Cc: freebsd-hackers@freebsd.org >>> Subject: Re: Writing a (BSD like) Operating Systems From Scratch >>> >>> "Welcome, Traiano" wrote: >>>> Hi All >>>> I've been read thousands of pages of FreeBSD and Linux Kernel source >>> code and books on the internals of BSD and Linux over the years in >>> attempt >>> to develop a complete understanding of operating systems (or at >>> least, UNIX >>> like ones). However, I feel that I'm as mystified as to the finer >>> details as >>> when I first started. So I've concluded that the best way to really >>> understand >>> the deep dark details of UNIX is to try and write one from scratch >>> (using the >>> general guidelines of standards like POSIX etc ...), and maybe taking >>> a peek at >>> BSD and Linux from time to time. My questions around this are: >>> >>> Sorry, but your questions & text (see mega line above, no folds ! >>> Ugh) tell me >>> >>> A) You dont know enough, & would be better working with an >>> existing >>> project, be it a BSD Linux Minix Sprite Mach whatever. Maybe >>> also doing some formal training in OSs eg a Uni. degree >>> in computing or whatever. >> >> >> Right on the mark, Julian! The don't know enough part especially, >> hence the _questions_ (Normally asked by people who don't know enough). >> May I ask where you get the divine wisdom to know where I "would be >> better working with" ? don't you think that would be best left up to me? >> So what if formal training in OSes is not an option to me ? Not all of >> us have the wealth and time, nor privilege of coming from a family >> that can >> afford such an education, like myself for example. What do you >> recommend for those of us who have neither the wealth nor luxury of >> time to pursue >> " a Uni. degree in computing or whatever." ? >> >> You appear not to realize that to even begin working with one of the >> existing projects, you'd best have a solid understanding of OSes to >> begin with, >> which brings up an interesting catch -22 that goes something like: >> >> "You can't join the club, because you don't know enough. You can't >> know enough 'till you join our club". >> >> Is that the case or am I mistaken ? > > I don't think there is any kind of "club". There are just peoples that > know better than others how does works one or many parts of the system, > but not the entire system and other peoples krowing other parts, etc. > > You'll see (if not already) that everytime you discover new things, you > discorver in the same time there is a lot to do more ! Even on a little > system on a classic computer (ARM, x86…) > >>> >>> B) You havent realised technology is moving faster & with ever more >>> more people working on OSs & tools, its like looking in >>> from the edge of an exploding galaxy & trying to understand >>> all within: by the time you do, its grown ! >>> >> >> May I ask how you jumped to that conclusion? What makes you think I >> want to keep at the cutting edge of everything? >> All I want to begin at the very basis and build up from there at my >> own pace, until I'm capable of building something very >> Basic, functional and something I can use to illustrate to myself the >> design principles involved in building operating systems. >> >> >>> C) If people devoted tons of time over years to help you along, >>> it would be their & your time wasted to achieve anothernice >>> OS time that would be better spent if you & they worked >>> together on improving an existing OS - see (A) above. >> >> >> Where did you get the idea that I'm asking for tons of time over years >> ? Have you a record of me going around the internet pestering people >> for answers on how to build operating systems? All I asked for was a >> couple of links and pointers, maybe a good book or two. Besides, I'd >> be of no using helping to build spacecraft if I can barely build a >> cart, so no, my time would not be better spent helping people who >> really have a clue to improve existing OSes. > > Dont be so aggressive. He is juste saying it has much more chances to be > a waste of time to _start and continue_ developping from scratch than > continue developping existing projects. Starting from scratch is > absolutely not the only way to learn by ourself. >> >>> Sorry it's not what you want to hear but modern OS are too big for >>> 1 man, & evolving too fast, even those called Jollitz Tannenbaum or >>> Linus, got >>> replaced/ supplemented by Teams. Choose a project team & an aspect/ >>> technology within the team, & that will be useful not a waste of time. >> >> I don't accept the conjecture that modern OSes are too big for one >> man. Modern OSes and their associated entourage of userpace and plugin >> modules maybe, but not the basic kernel/supervisor program. An OS is >> as big or small as you make it. I would like to eat this particular >> elephant one bite at a time. > > I agree on this point. If you take a very tiny micro-controller, for a > single (wo)man it is ok of course. But you'll learne about uC and not > about computers which are much more developped than uC. > > PS: can you please take care about line wrapping ? I don't krow if it's > the good word but the previous answer has'nt been broke to fitt on my > screen ;) > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" > I think that the best place to start is with this system: http://www.minix3.org/ And with this book: http://www.amazon.com/gp/product/0131429388/qid=1137005040/sr=8-1/ref=pd_bbs_1/102-1327526-9316154?n=507846&s=books&v=glance Like a Linus!