| The Linux Incompatability List
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25 Sep 04 |
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Saw this on /.
"The Linux Incompatibility list is
a wiki project that attempts to document hardware that is incompatible with
Linux rather than list what is compatible. In the wiki, it is possible to
add alternitives so as to push hardware manufacturers to make good binary
drivers, publish specifications, or even better, publish open
drivers."
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| Skolelinux: V1.0 with codename Venus is out! |
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25 Sep 04 |
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Skolelinux is made as free (as in speech) software, and is an overall computer solution based on school's resources and needs. It is based on Debian and runs very well on older hardware, too.
- Skolelinux is a network architecture tailored for use in schools.
- Skolelinux is designed to be easy and cheap to maintain.
- Skolelinux gives the students their own usernames, home directories and services.
- Skolelinux includes OpenOffice.org
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| Forth Database
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25 Sep 04 |
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Richard S. Westmoreland postd this to the Forth-ML.
In years past, we have implemented some extremely complicated databases in
Forth. The first was done in the mid 1970's for the company Cybek in NJ,
and it was used in some extremely complex applications. FORTH, Inc. also
did some very complex databases for other companies, one of which was still
in use last time I checked, at www.calmuni.com. That one was a
2-dimensional database, with a huge bit matrix in the center used to
calculate overlapping bonded indebtedness. A few years ago my contact there
told me that a state agency had just spent several million $$ trying to
replicate it using modern database tools, but the result was too large and
too slow to be usable.
In the late 1980's we added class-based techniques to it, which many people
liked (although I personally preferred the earlier, simpler version).
It's hard to describe the whole approach in a newsgroup post, though. It
certainly didn't resemble SQL!
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| Forth "versus" Whatever
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25 Sep 04 |
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From comp.lang.forth
>>Which brings me to an excellent 'forthism' I once read in a
>> newsletter. It stated:
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>> "You can do anything in Forth - but you must be prepared
>> to do it yourself."
In a recent discussion in c.l.functional, about why popular languages
are popular, I summarized the relationship between Lisp and Forth
more-or-less as follows:
"From the Lisper's perspective, every other language is a cute subset
of lisp; whereas from the Forther's perspective, every other language
is a cute extension of Forth."
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| Re: Forth, Befunge, Whitespace, or Malborge: which is hardest to write buggy code in?
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25 Sep 04 |
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(Source: comp.lang.forth)
>>Here is a version of Forth that runs under Windows, written in Whitespace:
>
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>>I can't get it to run. Do you think my browser has clobbered the code?
Hmmm. I did exactly as the web page[1] suggests: "What do you do? Simply
print it out and delete the file, ready to type in at a later date.
Nobody will know that your blank piece of paper is actually vital
computer code!" I sure hope that I didn't mistake my only copy of the
source code for an ordinary blank page!
Perhaps writing my Befunge[2] compiler in Malborge[3] and then making it
to a Forth[4] compiler written in Whitespace[1] wasn't such a good idea...
References:
1 http://compsoc.dur.ac.uk/whitespace/
2 http://dmoz.org/Computers/Programming/Languages/Befunge/
3 http://www.freebsd.org/cgi/query-pr.cgi?pr=28147
4 http://www.cbel.com/forth_programming_language/
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| Quote of the day
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25 Sep 04 |
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(Source: Kent Beck posted this to the XP-mailinglist)
This from a lean manufacturing consultant:
Find the simple path to what works and follow it, always looking for a
simpler path.
Patrick D. Smith
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| SCRUM vs XP
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25 Sep 04 |
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(Source: XP-mailinglist; thoughtful post by Ken Schwaber) Scrum is purely a project/product management process that can be applied to software projects, hardware projects, marketing projects, and any mix of the above. It does not contain engineering practices or any specific work practices. It is instead a way to maximize the ROI of work.
People who use Scrum in software development environment often adopt one or more of the XP practices to improve the engineering practices of the develpment organization. Scrum calls for an increment of potentially shippable product functionality every iteration. This means a fully cleaned up, refactored, tested, documented ready to go increment. Many organizations are incapable of this. It is easy to bring in XP practices because they are excellent and both Scrum and XP are pretty radically agile.
Project managers using Scrum are called ScrumMasters to differentiate the type of work they do ... they facilitate, manage the process, and optimize the team's productivity. They don't tell the team what to do, nor do they set of pairs of programmers, or parse out user stories. During the iteration, the team is entirely self- organizing ... whether it is doing software development or anything else related to the increment of functionality they are building.
XP seems to focus on team productivity... doing something the right way and as productively as possible. Scrum does this some, but instead focuses more on doing the right thing, getting ROI from building the 20% of the functionality that is necessary to get the value and maybe not building the rest.
We've implemented Scrum without telling the customer, users, or stakeholders. We've done this in one day. We seduce them into iterative, incremental development where they collaborate with us on what to do next. XP seems to require a steeper implementation curve with less acceptance from the users and customers. Scrum can't keep
the customers away.
Estimating is a subtle diffrence that points out the XP and Scrum dividing point. XP works hard to estimate very finely defined stories, and to measure and improve these estimates. Scrum keeps the requirements more broad, more in general user terms that are analyzed during the iteration. Estimating isn't as important. The team does what it can, and gets better and better at figuring out how much it can do each iteration as it learns each other, the business domain, and the technology - iteration by iteration. We care more about delivering business value that having defensible estimates, which become meaningless in a collaborative setting.
Scrum also has a formal methodology that lays out how to scale Scrum to any sort of project with any number of people in any number of locations ... all based on the optimized 7 person team. This is an important mangement requirement, but not so important to an engineering discipline like XP.
I feel we are blessed to have such compatible practices and processes to apply to our software engineering projects.
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| [XP] RSS for Xprogramming blog
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25 Sep 04 |
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| The Rise of ``Worse is Better''
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25 Sep 04 |
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(Source: Richard Gabriel) Good characteristics:
1) Simplicity-the design must be simple, both in implementation and
interface. It is more important for the interface to be simple than the
implementation.
2) Correctness-the design must be correct in all observable aspects.
Incorrectness is simply not allowed.
3) Consistency-the design must not be inconsistent. A design is allowed to
be slightly less simple and less complete to avoid inconsistency.
Consistency is as important as correctness.
4) Completeness-the design must cover as many important situations as is
practical. All reasonably expected cases must be covered. Simplicity is not
allowed to overly reduce completeness.
www.jwz.org/doc/worse-is-better.html
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| Introducing agile methods if the customer is obsessed by dead trees
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25 Sep 04 |
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(Source: posting to agile-testing@yahoogroups.com by John Goodsen) I think
a big mistake many of us make trying to introduce Agile development
practices, is we fall into the trap of agreeing that we are not providing
documentation. If your organization wants to see documents along the way,
don’t tell them they can’t have it! Tell them they will have
the most up to date documentation that they have ever seen, because you are
going to generate it directly from the code. Our teams use an XP process.
It doesn’t take much to tie in a tool to auto-gen design specs from
the code and if you are automating customer tests, you can put description
in the headers of tests methods and use a javadoc based generation of a
"requirements specification"… so rather than view your
organization as an enemy that requires an "undergound attack",
listen very carefully to what people are asking for and figure out how
Agile approaches can deliver it. We are not the enemy. We are the
liberator. We have exactly what they want, but we often fail to match up
our Agile solution with what the stakeholder is asking for.
When an organization wants more than the Agile process requires, it is easy
to show the additional cost each iteration, and as the team builds
credibility the customer/stakeholder(s) might be less inclined to want to
spend money each iteration producing documentation.
So have some courage, tell your stakeholders that they can have it
(whatever "it" is) if they want it and then make sure you follow
up with giving them a good picture of the cost and value they get from
"it". It’s their money - let them blow it if they want to.
Let them slow the velocity by asking for non-code related items. All you
can do is make it visible and help them down the path of figuring it out.
The sooner you start delivering some working code, the sooner you’ll
have the credibility to address their real process issues. "It"
will become less important the more iterations you deliver working tested
code.
The hard part is getting code started, right? Maybe you can disguise the
first few iterations as "prototyping" and use TDD as the process
for your prototyping? :-)
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| What is XP?
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25 Sep 04 |
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Ron Jeffries posted this well known Kent Beck quote in the XP-mailinglist.
They talk about the 2nd ed. of XP Explained by Kent Beck.
But anyway, when I last asked Kent what XP is, he said
"XP is a community of software development practices based on
values of simplicity, communication, feedback, and courage".
That was about two or three years ago.
I look forward to seeing the second edition as well.
I'm sure it will be enlightening ...
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| .. like Xmas
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25 Sep 04 |
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I came across this nice discussion between Phlip and Juergen Ahthing in the
XP-ML
"Without test-first and refactoring, clients think
they must assemble as many program requirements as
they can afford to have written. This effort snarls
all relative business priorities together, making
Scope Control impossible. It obscures opportunities
for simplification. Designing and implementing many
features all at once is very hard, leading to our
industry's reputation for very large failures. Putting
tests in front of development's inner cycle permits an
outer cycle of incremental feature growth. That
relieves the Customer of the responsibility to predict
the future and guess which complete set of features
will maximize productivity."
.. Juergens answer:
Nice description.
Sometimes I try to explain that to non technical people
with the following picture:
If you have only one chance to get your wishes on a
list, it is like Christmas for a child. You make sure
you get every little wish on that list and hope for the best.
If you are sure that you can get your wishes on the list
at any time. You will just put the most important ones
there which come to your mind easily.
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| XP success story: Sabre takes extreme measures
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25 Sep 04 |
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(Source: Computerworld) Using extreme programming practices, Sabre Airline
Solutions has reduced bugs and development times for its software products.
Sabre Airline Solutions had many years of experience with its AirFlite
Profit Manager, a big modeling and forecasting package that many airlines
use to wring more income out of flight schedules. Even so, Release 8 of the
software was four months late in 2000 after final system testing turned up
300 bugs. The first customer found 26 more bugs in the first three days of
its acceptance testing, and subsequent joint testing by Sabre and the
customer uncovered an additional 200 defects. www.computerworld.com/softwaretopics/software/story/0,10801,91646,00.html
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| Case stories
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25 Sep 04 |
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Been skimming the XP-ML this morning.
About the $200M Oracle-Ford Desaster: the management did not give them
enough power to go fully agile
Chet Hendrickson:
It was a very frustrating situation. The team asked Don and me
to help with preventing the Oracle consutants from making changes
directly to the production system. This was about $150 million into the project.
We tried to sell them on a more agile approach (as you might imagine), but by
this time they were pretty far gone.
It was unfortunante that we were not operating at a level in the organization
that would have allowed us to get the plug pulled sooner.
chet
Georg Tuparev has a nice case story, too: speak out if you are put on a
death march.
Few years ago I was called to lead a huge team stuck in one and half
year design phase. The team was supposed to build a control software
for a network of telecom satellites. Cannot disclosed names and
resources, but one could imagine ...
Three days in the project I had a phone conference with the CxO's of
both companies involved. Told them that the way it is going no
satellite will ever fly and that I know a better way. After getting
green line, the design document was burned with a small celebration at
a BBQ, and 85% of the initial team members were sent to an indefinitely
long vacation. With the rest (15%) of the team we had the first
functioning version 2 months ahead of the schedule and 50% lower then
expected expenses.
So the lessons:
- it is never late to change direction of a project in order to save it.
- I do not agree with Kent that this is a sad story. If you are a good
programmer put on a death march project you should speak out! If no one
listens - walk away. There is just one very precious life in front of
us - do not waste it! And if these folks wasted 2 years of their lives,
well, it is their business ... but they should not expect my
sympathies.
BTW, Philip is right - the project I was telling about had a 9 months x
40 people "Big Requirements Up Front"!!! Then the design started...
Just my 0.02
Georg Tuparev
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| Just Ship, Baby
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25 Sep 04 |
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(Source: Kent Beck) Short two page essay: The focus on shipping is not an
excuse for cutting corners, but perfect adherence to the practices is no
excuse for not shipping. groups.yahoo.com/group/extremeprogramming/files/just%20ship.pdf
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| Unit Tests -- just do it!
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25 Sep 04 |
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Been coding a lot these days on SmallWorld.
I try to be disciplined and continue adding unit tests to the hundreds of
unit tests wherever sth. could go wrong, but ever again I go off the track
and code several methods and even entire classes without any tests.
It’s simple stuff and hey, this is ruby :-).
Then I sit here for 3 hours trying to understand why the dammed computer
does not do what it should. It’s that feeling I hate most. You waste
time .. I mean I could as well go skiing or drink a bottle of vodka ..
would be about the same productivity progress on my code and at least I
would enjoy the sun.
After hitting my head long enough and starting to isolate the stuff .. I
found it .. I had forgotten one return in a most trivial three line long
method. Shame on me. Now I will go back to being test-infected. test-first
is even better. Dammit .. sorry for the rant, but I doubt there are many
systems like computers where one comma at the wrong place can make
everything go boom. Oh well, try to modify the DNA and do not know what you
are doing. :-).
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| fit
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25 Sep 04 |
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Ward Cunningham has released an acceptance testing tool called fit fit is about tests that people can read.
The Cook’s Tour
offers an excellent howto to get yourself and your customers into the
test-writing mode.
An intro
article by Bill Wake.
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| CIO magazine current issue all about agile... (IT oriented, but)
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25 Sep 04 |
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Denis Haskin posted this to the XP-ML. lnik
I assume this popped up on everyone else's RSS aggregator as well, but...
From Darrell Norton's blog [1] and Artima developer forum [2]: the
current issue of CIO magazine is all about agility:
http://www.cio.com/archive/081504/index.html
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| Advantages of Extreme Programming
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25 Sep 04 |
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(Source: Kevin Smith post to extremeprogramming@yahoogroups.com) After a
couple years of pitching XP, it became very clear to me that XP has
different key advantages for different audiences. You’ll have to
decide whether to pitch to a single audience, or try to cover several.
For developers, XP allows you to focus on coding and avoid needless
paperwork and meetings. It provides a more social atmosphere, more
opportunities to learn new skills, and a chance to go home at a decent hour
each night. It gives you very frequent feelings of achievement, and
generally allows you to produce code that you feel good about.
For the Customer, XP creates working software faster, and that software
tends to have very few defects. It allows you to change your mind whenever
you need to, with minimal cost and almost no complaining from the
developers. It produces reliable estimates so you can coordinate your
schedule easier.
For management, XP delivers working software for less money, and the
software is more likely to do what the end users actually want. It cuts
risk in a couple ways: 1) It allows you to "pull the plug" on
development at almost any time, and still have highly valuable code, and
probably even a valuable working (if incomplete) application. 2) It reduces
your dependence on individual superstars, and at the same time can improve
employee satisfaction and retention.
The biggest disadvantage: It’s hard. It’s difficult to get many
developers to accept the practices, and it takes a lot of discipline to
keep doing them all. Customers may not like the idea of having to be so
involved. Management may expect fixed-cost, fixed-scope estimates, which XP
teams often refuse to create (because they are usually incorrect with any
methodology).
Also, certain people may feel their jobs are being threatened, particularly
architects, testers, and project managers. "Cowboy" coding
"superstars" may dislike the reduction in fame, attention, and
adreneline from "saving" the project at the last minute.
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| XPlorations: The Humble Yo
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25 Sep 04 |
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(Source: Bill Wake) "The Humble Yo" The humble "Yo!" is
a simple convention for getting help. link Nice
explanation of why not asking for help can actually hurt the team.
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