The Journal of AUUG Inc. Volume 23 ¯ Number 3 October 2002 Features: Dynamically Tune up a File System 12 SGI Shatters World Performance Record 14 Book Review: Multitool Linux: Practical Uses for O~pen Source Software 15 Advocacy for Open Source in Government 16 Multi-Account Email with mutt 18 Amanda CD-RW Taper 19 Dynamically Expand a File-system to a Single Stripe instead of to Several Concatenated Stripes 20 How to Install SuSE Linux 8 on your Xbox 21 Chrooting all Services in Linux 23 Avoiding Security Holes when Developing an Application - Part 5: Race Conditions 28 Kerberos: The Watchdog of the Ether 34 Process Tracing using Ptrace 37 Exploring Perl Modules - Part 1: On-The-Fly-Graphics with GD 40 An Introduction to GNU Privacy Guard 46 Commentary: Why Linux will Conquer the World 56 News: Public Notices 8 AUUG: Corporate Members 12 AUUG: Chapter Meetings and Contact Details 63 Regulars: President’s Column 3 /var/spool/mail/auugn 4 My Home Network 8 AUUGN Book Reviews 10 ISSN 1035-7521 Print post approved by Australia Post - PP2391500002 AUUG Membership and General Correspondence The AUUG Secretary AUUG Inc Editorial PO Box 7071 Con Zymaris Baulkham Hills BC NSW 2153 [email protected] Telephone: 02 8824 951t or 1800 625 655 (Toll-Free) Facsimile: 02 8824 9522 I’m noticing a trend, and I don’t think I’m the only Emaih [email protected] one. The trend I’m seeing is the grass-roots re- energisation of the world of Unix, the world of open AUUG Management Committee computing platforms and the world of AUUG. These Email: auugexec~auug.org.au three are fully, inexorably integrated. When one rises, President they all rise. The catalyst which is causal and Greg Lehey inspiration to this rise is open source software, in PO Box 460 both methodology and philosophy. K’s this Echunga, SA, 5153 renaissance of AUUG, which is my focus today. Bus. Tel (08) 8388 8286, Mobile 0418 838 708, Fax (08) 8388 8725 <[email protected]> Renaissance. A word which means rebirth in Latin by way of simple translation, but which conveys much Immediate Past President much more. Here’s how it comes to mean what we David Purdue understand of it today. Sun Microsystems Level 6, 476 St Kilda Road Melbourne, Victoria, 3004 In the 64 Century, the Byzantine emperor Justinian Phone: +61 3 9869 6412, Fax: +61 3 9869 6288 ordered the closure of the Academy (nee Plato’s) in <David.Purdue@auu~.or~q.au> Athens, as it was considered to be a pagan remnant. Vice-president This, and the contemporaneous burning of the Great Malcolm Caldwell Library of Alexandria, and the evisceration of its last Bus. Tel (08) 8946 6631, Fax (08) 8946 6630 librarian, Hypatia, bought about what we colloquially <[email protected]> know as the Dark Ages. Inspiration, methodology and Secretary philosophy were lost to the western world for almost a David Bullock a thousand., but thankfially not to the Arab world. 0402 90t 228 <[email protected]> Ancient Greek knowledge, garnered from translated Treasurer Arabic texts, stored in libraries in Islamic Spain in the Gordon Hubbard 124 century precipitated a rebirth; an explosion of Custom Technology Australia Pry Ltd scholastic and academic knowledge in western and Level 22, 259 George Street, Sydney NSW 2000 southern Europe: the Renaissance, from which flowed Bus Tel: 02 9659 9590, Bus Fax: 02 9659 9510 <[email protected]> the Enlightenment and political and social reforms, the formulation of the modern scientific method and Committee Members our world as we Imow it. Sarah Bolderoff FourSticks Suite 2, 259 Glen Osmond Rd, These epochal changes flowed from the ideas and Frewville, South Australia, 5065 tenets of the ancients, to become the inspiration, <[email protected]> methodology and philosophy of the modern world. Adrian Close Old, solid principles which had examined, Mobile: +6t 412 385 20t, <[email protected]~l.au> c6iitemplated and sometimes resolved many a complex problem, were worth re-introducing, to help Stephen Rothwell avoid the often painful task of knowledge acquisition IBM Australia, Linux Technology Center from first principles. The results, as we all know, were 8 Brisbane Ave, Barton ACT 2600 Business phone: 02 62121169 breathtaking. <Stephen.RothwellL~auug.org.au> The conceptual bit-mask of the Dark Ages may also be Andrew Rutherford applied to our industry. I see AUUG fulfilling a lagu Networks, 244 Pirie St Adelaide, SA, 5000 spiritually equivalent role with respect to the re- Bus. Tel (08) 8425 220t, Bus. Fax (08) 8425 2299 introduction of the ideas, tenets and principles. Many <Andrew.Rutherford@au ug.org.au> or most of the problems and issues (technical, ethical and social) wrought by complex, vastly inter- Mark White apviva technology partners connected computing systems, have been examined, P. O. Box 1870, Toowong QLD 4066 contemplated and sometimes resolved by the people Bus Tel 07 3876 8779, Mobile 04 3890 0880 who constitute AUUG and its sister organisations. We <[email protected]> were there. We have done this. We can do this again. Let’s seize this renaissance of advanced computing AUUG Business Manager systems based on Unix, and let us help the IT world Elizabeth Carroll by shedding light on how best to move forward. Let us AUUG Inc accept this challenge and regain full relevance to both PO Box 7071 Baulkham Hills BC NSW 2153 the advanced technical realm and also the popular. <busmgr(~auug.org.au> Let’s teach to the world to Carpe Unix! Cheers, Con AUUGN Vol.23 ¯ No.3 1 - October 2002 AUUGN Editorial Committee Contribution The AUUGN Editorial Committee can be reached by sending email to: [email protected]~.au Deadlines for AUUGN Or to the following address: AUUG Inc in 2002 PO Box 707t Baulkham Hills BC NSW 2153 Editor: Volume 23 o Number 4- December 2002: November Con Zymaris th, 15 2002 Sub-Editors: Frank Crawford, Mark White Volume 24 o Number 1 - February 2003:March 15~, Contributors: 2003 This issue would not have happened without the transcription and editorial efforts of Gary R. Schmidt" <~qrschmidt~acm.org>, Rik Harris <rik@,kawa]a.net>, Raymond Smith <[email protected]>, David Lloyd <[email protected]>, Public Relations and Marketing: AUUG Incorporated grateffflly acknowledges Elizabeth Carroll the support of its corporate sponsor: AUUGN Submission Guidelines Submission guidelines for AUUGN contributions can be obtained from the AUUG World Wide Web site at: www.auug.org.au Alternately, send email to the above correspondence address, requesting a copy. AUUGN Back Issues A variety of back issues of AUUGN are still available. For price and availability please contact the AUUG Secretariat, or write to: AUUG Inc PO Box 7071 Baulkham Hills BC NSW 2t53 Conference Proceedings A limited number of copies of the Conference Proceedings from previous AUUG Conferences are still available. Conthct the AUUG Secretariat for details. Mailing Lists Enquiries regarding the purchase of the AUUGN mailing list should be directed to the AUUG Secretariat. Disclaimer Opinions expressed by the authors and reviewers are not necessarily those of AUUG Inc., its Journal, or its editorial committee. Copyright Information Copyright © 2002 AUUG Inc. All rights reserved. Portions © by their respective authors, and released under specified licences. AUUGN is the journal of AUUG Inc., an organisation with the aim of promoting knowledge and understanding of Open Systems, including, but not restricted to, the UNIX© operating system, user interfaces, graphics, networking, programming and development environments and related standards. Copyright without fee is permitted, provided that copies are made without modification, and are not made or distributed for commercial advantage. AUUGN Vo1.23 * No.3 - 2 - October 2002 President’s Column industry which have to affect AUUG. Most notably, of course, there’s "Open Source". Or is Greg Lehey <Gre.q.Lehev~,auuff.or.q.au> that Open Systems? Or Open Computing?. Or Open change, n. [a. AF. chaunge, OF. change (= Standards? Or just plain Free Software? The Board Pr. camge, camje, Sp. cange):- late L. has discussed the terminology at length and we’re still far from agreeing. Anyway, we’re moving towards cambi-um exchange (Laws of Lombards), less proprietary solutions. Ten years ago, AUUG was f. cambire, to change.] 1. a. The act or a stronghold of proprietary UNIX. Nowadays you fact of changing; substitution of one almost have to look for people who use any thing for another; succession of one proprietary UNIX except for Solaris. The majority of thing in place of another. 11. Sc. An ale- the system-related papers at this year’s conference house; = change-house. --Oxford Eru31ish were about Linux, followed by BSD (including Apple’s Dictionary MacOS X). Even the vendors of proprietary UNIX are jumping on the bandwagon, including both of our We’re certainly living in an era of change, and AUUG corporate sponsors. has not been excepted. When I joined AUUG a little over two years ago, I had little intention of taking a This development has caused a lot of introspection on serious part in its org .ar~ization. Now I’m reminded of the board. Linux users already have their own very a saying we had at university: "Too years ago I didn’t active organizations, and there are also a number of know how to spel presadent, and now I are one". BSD groups round the country. The Linux users run their own very successful conference every summer, It’s not an easy office to slip into. I spent one year as the linux.conf.au.