' \
| sed -r 's! A .*>(.*)<.*!\1!' \
| sed -r 's!\(([0-9]{4})(/(I{1,3}|I?V|VI{1,3}|I?X))?\)$!| \1!'
}
for URL in $(get_top_250_chart); do
get_movie_and_year "$URL"
done
# vim: set ft=sh tw=70 sw=2 sts=2 et:
Also, this version correctly parses—for example, "Crash (2004/1)"
is changed to "Crash | 2004".
Felix C. Stegerman
10 | October 2008 www.linuxjournal.com
[LETTERS]
having were due to the drivers and the card
being substandard. So, we invested in an
eight-port, 9000 series 3ware card.
It turns out that 3ware has to test every
firmware revision of every SATA drive with its
cards, because many perform very poorly.
After losing three drives, we tried to replace
a bad one with a 500G drive, because we
couldn't get a 400G drive at local stores, and
performance fell through the floor. I updated
the firmware, researched on 3ware.com and
called 3ware. It came down to poor quality
control on the part of SATA manufacturers,
and there was nothing we could do about
the drives we had. In summary, if you use
SATA RAID, make sure you check 3ware's
compatibility list.
The bad news is that you probably don't
know the firmware revision until after you
open the drive and use it. Refunds get
really tricky after that, so you'll probably go
through a few drives trying to find good
ones. It's probably a good idea to have mul¬
tiple hot spares in your system and to have
some pretested drives lying around.
JT Moree
Try Hyperic HQ
I'm writing in response to Jeremiah
Bowling's article on Zenoss in the August
2008 issue of LJ. Although I'm sure it is a
good product, there is another one that
provides the same, if not more, capability
with less setup time: Hyperic HQ. I believe
Linux Journal mentioned it in the New
Products section a while back.
Hyperic uses XML over HTTPS, using agents
installed on hosts to provide metrics back to
the HQ Server. It can monitor 10s of 100s of
different metrics across different platforms,
and it is open source. The process of adding
devices and services is performed by the
agent through its detection capabilities,
which are reported back to the server auto¬
matically when the agent is registered. SNMP
isn't even needed unless desired. It is open
source, but Hyperic sells an enterprise version
that comes with support. The only thing it
seems that Hyperic doesn't have that Zenoss
does have is the geographic mapping capa¬
bility. Hyperic provides all the metric charts,
alerting, roles and monitoring that Zenoss
does. I urge those who try out Zenoss to take
Hyperic for a spin also. I'm using it at work,
and it makes monitoring systems a breeze.
One final note, Jeremiah discusses the
setup of SNMP and the use of community
strings. Although specifying a custom
community string is better than the
default, anyone still can sniff the network
to determine what the string is, so it really
doesn't provide much security. As I men¬
tioned above, Hyperic agents communi¬
cate with the Hyperic server using HTTPS,
1 2 3 4 5
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Intel or AMD. Ethernet or InfiniBand. Linux or Microsoft
Windows HPC Server. Now you can have a uniform set of HPC compilers
and tools across all of your x64 clusters. PGICDK compilers and
tools are available directly from most cluster suppliers.
Take a free test drive today at www.pgroup.com/reasons
PGI CDK Cluster Development Kit
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Other brands and names are the property of their respective owners.
[LETTERS]
which we all know really is secure.
I appreciate Jeremiah's article, despite my
mention of a similar product. I wasn't
aware of Zenoss and always am glad to
have my awareness expanded.
Brandon McCombs
Look for an article on Hyperic HQ in an
upcoming issue. — Ed.
Failed to Mention the Cost
I was interested to see an article about
building E-Ink devices in the August
2008 issue of LJ. I acknowledge that the
article involves a clever bit of engineer¬
ing, but you fail to mention that display
you used, AM200, costs $3,000 US
(store.nexternal.com/shared/StoreFront/
default.asp?CS=eink&StoreType=BtoC&
Countl=555858790&Count2=472999215).
It's disappointing this fact was left out
to make the project sound more reason¬
able. Normally, I've found your articles
are more honest about the costs.
Jim Putman
It's a Small World
Although I always enjoy reading about
scientific applications for Linux, "One Tale
of Two Scientific Distros" by Doc Searls in
your August 2008 Upfront section, hit
particularly close to home. My cousin,
David Auty, is an astrophysicist, currently
researching neutrino oscillations at
Fermilab. Here's a link to a brief descrip¬
tion of his work: www.sussex.ac.uk/
physics/profile104724.html.
James Knott
More on SATA
The article "One Box. Sixteen Trillion
Bytes" [August 2008] showed the
use of a 3ware utility to interrogate
performance of the RAID-connected
SATA disks. Having some systems
with problematic hard disks, that
got me wondering what general
utilities are available to support
SATA disks—for example, what
goes beyond hdparm?
I discovered that the newer sdparm
utility is designed to support SATA
disks. However, despite extensive
Google searches, other than one
good overview, there is a dearth of
how-to guides that highlight what
one can safely change, or the likely
or possible implications of changing
the various parameters.
I'm sure a future article in Linux Journal
by an sdparm expert would be of great
interest to many since most systems are
now using SATA or SAS drives rather
than PATA.
David Cartwright
LINUX
JOURNAL
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12 | October 2008 www.linuxjournal.com
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FRONT
NEWS + FUN
WHAT'S NEW
IN KERNEL
DEVELOPMENT
Keeping firmware in
[ “ U the kernel is a some¬
what controversial
issue, because it
means keeping binary
blobs of data in an
open-source project.
But removing it, as David Woodhouse
is trying to do, turns out to be controver¬
sial also. Folks like David S. Miller are
violently opposed to the idea on the
grounds that it would break certain
drivers (like tg 3) or make them much
worse. Also, it takes a part of the kernel
that essentially had been approved by
Linus Torvalds —even in binary form—
and puts it in the hands of someone
else. Unlike GCC, libc and other projects
on which the kernel depends, this
external firmware project would not be
anything like a universal tool; it just
would be a key part of the kernel that
was stored and maintained outside the
official source tree.
But, now that the effort actually is
underway, it may be unstoppable. A lot
of folks find the problem interesting on a
technical level, which generally means
they'll eventually find solutions that satisfy
everyone. For now, it seems as though
firmware definitely will be relegated to
its own little spot in the kernel sources.
From there, it could end up getting a
separate git tree altogether.
Willy Tarreau has adjusted the 2.4
release schedule, based on the results
of an informal survey of existing 2.4
users. He found that about 80% of
current users didn't upgrade, because
a lot of their employees or customers
would be inconvenienced by any hiccups
in the upgrade path or by the downtime
required to do the upgrade successfully.
The rest of the users could upgrade easi¬
ly if they wanted to or if they knew how,
but they either were running it on their
home systems and simply didn't need
the benefits of 2.6, or they were running
it on firewalls, routers and so on, and
the folks maintaining them didn't have
a clearly defined upgrade path—
although Willy reckoned it wouldn't
be too hard to do.
From all this, Willy concluded that
he would put out stability fixes more
frequently, so people could get what
they needed to fix whatever small
problems remained on their 2.4 systems,
but that he'd slow down on putting
out major releases, and do that only
for versions with new PCI IDs, big
driver updates, compiler support changes
and so on. Willy also suggested that
someone write up a complete descrip¬
tion of the differences between 2.4
and 2.6 and how to address all the
problems of upgrading.
It's useful to be able to write to
files under CramFS, SquashFS and
even mounted CDs, knowing that the
changes will not be permanent and will
go away after a reboot. Arnd Bergman
has recently implemented this kind of
temporary write support for CramFS,
and Phillip Lougher also is planning to
write a similar feature for SquashFS. A
lot of folks objected to Arnd's approach
though, saying that this kind of thing
should be accomplished by using
UnionFS to stack something like TmpFS
on top of CramFS. But, it turns out that
UnionFS is kind of a mess and not really
able to do the job well. Some folks, like
Phillip, also feel that stackable filesystem
USER FRIENDLY by J,P. Frazer
ts THAT. .SOME KIND OF
ALTERNATE MUSIC?
I ITS ^HORDSTATS*
/ A PERL SCRIPT THAT
MONITORS A SYSTEM
AND RETURNS MACHINE
GENERATED MtiSlG
N (r^\ t>UM
£>OOP
DUM
OH...THAT'S
INTERESTING,,*
/ BOOP DE DOOP DOOP
/ ,.,DUHDUH
...I THINK ITS
PLAYING THE
THEME FROM
"JAWS." p| TR/QU |T
/ Mlu TeAstMS ™e
support should go right in the VFS,
instead of clunking around in a filesys¬
tem of its own.
The uproar against writing one-offs
for each affected filesystem (CramFS,
SquashFS and so forth) subsided when it
became clear that CramFS and SquashFS
would be the only two filesystems to do
this, except for perhaps ISO9660. At
least with a small number of filesystems,
the amount of duplicated effort would
not be too great. But, the people inter¬
ested in making UnionFS the canonical
method of accomplishing this sort of
thing apparently have redoubled their
efforts. So, it may be that both groups
will get what they need soon enough.
Geert Uytterhoeven asked when
SquashFS would be accepted into the
kernel tree, and Phillip Lougher said that
he actually was making some major
changes, after which it would presum¬
ably take some time for the code to be
reviewed by users and any remaining
sizable bugs shaken out. Among the
changes, Phillip is considering changing
the on-disk data layout, which would
solve certain problems but break back¬
ward compatibility.
The venerable AdvFS filesystem
has been released by Hewlett-Packard
under the terms of the GPL version 2.
This filesystem has been around since
the 1980s, supports journaling and file
undeletion, and is very fast in general.
Nowadays, there are plenty of journaling
filesystems, but this release represents a
solid and excellent body of code—and a
really terrific body of documentation—
available to the Open Source world for
the first time. The AdvFS release is not,
as Linda Knippers from HP has pointed
out, a port of the filesystem
to Linux. HP sees this release
as providing a lot of cool
stuff for open-source devel¬
opers to use in any various
projects where they might
be useful. But, it's also likely
that some kernel folks
will want to do a real
port. So, we probably can
look forward to seeing
AdvFS in the main kernel
tree at some point.
— ZACK BROWN
LNMRIMniDN
14 | October 2008 www.linuxjournal.com
[UPFRONT
New Videos on LinuxJournal.com
As some of you may have noticed, there have been a
number of new videos on LinuxJournal.com. If you haven't
noticed, well, get over to LinuxJournal.com to learn some¬
thing new in one of our new tutorial screencasts. When you
are not enjoying Shawn "Gadget Guy" Powers' antics, you'll
surely find something interesting and useful in our new series
of videos. Visit www.linuxjournal.com/video to check out
the selection. Perhaps you'll learn how to edit video with
FFmpeg or something else to add to your bag of tricks.
As always, Shawn will continue to bring you reviews
and commentary from his Gadget Guy studio, so keep
watching those too. There's so much to enjoy!
— KATHERINE DRUCKMAN
They Said It
Our passion is about Linux for human beings, it's not
Linux for Linux specialists, or Linux for anything other
than the people who we care about.
...our goal, very simply, is to make sure the free
software ecosystem can deliver a Mac OS-like experi¬
ence, or an experience that will compete with the Mac
OS. We see Apple as the gold standard of the user
experience. We believe that, while it can be a challenge,
the innovation inherent in the free software process can
deliver an experience that is comparable and in many
ways superior.
Proprietary drivers are a horrible kludge; they're a
little bit like introducing a cast iron pot into a titanium
machine. You have something that is inherently brittle
and therefore reduces the value of the whole.
—Mark Shuttleworth, itmanagement.earthweb.com/osrc/article.php/
12068_3757246_2
For every artificial scarcity, there's an equal and opposite
artificial abundance.
—JP Rangaswami, a talk reported at Rebootl0, twitter.com/dweinberger/
statuses/844937650
If you provide your customer with solutions, you'll have a
well-defined market. But if you provide your customer
with the opportunity to create new solutions, your cus¬
tomer will create new markets for you.
—Bob Frankston, private e-mail message
Communications tools don't get socially interesting until
they get technologically boring....a tool...has to have been
around long enough that most of society is using it. It's
when a technology becomes normal, then ubiquitous,
and finally so pervasive as to be invisible, that the really
profound changes happen....
—Clay Shirky, from his book Here Comes Everybody, page 105
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Intel co rpa rai ion or its subsidiaries. in trio united stales and
other countries.
Prices and availability subjecl io change without notice.
Not responsible lor typographic errors.
Powerful.
Efficient.
[UPFRONT
It's All Like...What?
Google phrase searches can produce
results that seem like random
answers to a Rorschach test—only
more amusing. Here are the top
results (on a day in July 2008) for
"The Internet is like...":
■ "a vast uncataloged library"
■ "a vagina"
■ "Joey Bishop"
■ "a series of tubes"
■ "Microsoft"
■ "alcohol in some sense"
■ "a newspaper"
■ "going down the Chinese road"
Closer to home, "Linux is like...":
■ "switching from a car to
a motorcycle"
■ "a pizza"
■ "ice cream—too many flavors
to choose"
■ "a fixed-wheel bicycle"
■ "turning on your first computer
and figuring out what all those
weird boxes did"
■ "a common cold"
■ "a whole new species"
■ "Ubuntu, only different"
Our hat tip for this observation
goes to reader Mike Warot. (See
"What They're Using?" on page 17
for more about Mike.)
— DOC SEARLS
Laundering Blog Layouts
for Mobile Devices
Whenever I run across something
new, cool and Web-based, I check
Netcraft's "What's that site using?"
to see whether the site's servers are
running on Linux. You can't always
tell, and the results can be misleading,
but it's a good first sniff test.
That's what I did with MoFuse
(www.mofuse.com), and it
passed. "Linux Apache/2.0.63 (Unix)
mod_ssl/2.0.63 OpenSSL/...", it said.
What's cool about MoFuse is that
it launders the layout complexities
out of blog posts and turns them
into simple lists of linked headlines. It
does this free if you like, or you can
pay for extra services, such as adver¬
tising revenue sharing and URLs that
don't have "mofuse.mobi" in them.
MoFuse isn't alone, of course.
Mippin (www.mippin.com) has
been doing similar stuff for a while,
and Netcraft shows them running
Linux too (Red Hat, in this case).
And Google, naturally, also has
an interface that can turn any blog
into "mobile, blog name, whatever".
Of course, that's Linux too.
In any case, the percentage of Web
surfing via mobile devices is going to
skyrocket—especially after the next
generation of unlocked, uncrippled
Linux-based devices start hitting the
market. Formatting for the hand
screen will shift from exception to rule.
— DOC SEARLS
LJ pays $100 for tech tips we publish. Send your tip
and contact information to techtips@linuxjournal.com.
Did you know Linux Journal maintains a mailing list where list members discuss all things
Linux? Join LJ's linux-list today: http://lists2.linuxjournal.com/mailman/listinfo/linux-list.
LJ Index,
October 2008
1. Number of Firefox 3.0 downloads in 24
hours starting June 17, 2008: 8,002,530
2. Position of the above download number
among Guinness World Records: 1
3. Minimum millions of Firefox users: 180
4. Minimum number of countries in which
Firefox is used: 230
5. Millions of dollars in VC funding for
open-source vendors in 2007: 328.5
6. Millions of dollars in VC funding for open-
source vendors in first half of 2008: 321.3
7. Percentage increase in VC funding in first
half of 2008 over 2007: 62
8. Total billions in open-source funding
through first half of 2008: 2.80
9. Age in years of a reported bug in BSD
discovered in May 2008: 25
10. Linux's market share percentage of counted
browser visits in January 2007: 35
11. Linux's market share percentage of counted
browser visits in January 2008: 64
12. Linux's market share percentage of counted
browser visits in June 2008: 80
13. Linux year-over-year percentage growth in
server sales in Q1 2008: 8.4
14. Linux server revenue in billions of dollars
for Q1 2008: 1.8
15. Linux-based server percentage of all server
revenue: 13.7
16. Number of Linux-based laptops to be
distributed to students in the Tamil Nadu
state of India: 100,000
17. Price in dollars for Ubuntu Hardy Heron
(8.04) in ValuSoft boxes at Best Buy and
Amazon: 20
18. Number of Linux distros listed on
DistroWatch's Page Hit Ranking: 100
19. Position of Ubuntu among top distros in
the six months ending July 16, 2008: 1
20. Position of OpenSUSE among top distros
in the six months ending July 16, 2008: 2
Sources: 1-4: SpreadFirefox.com
5-8: 451 Group j 9: Thelnquirer
10-12: NetAppLications.com
13-15: International Data Corp (IDC)
16: LinuxWatch 117: DesktopLinux.com
18-20: DistroWatch.com
16 | October 2008 www.linuxjournal.com
[UPFRONT]
What They're Using
Mike Warot
Linux converts don't always come in
groups. Among IT folks, they tend to
come one by one. Case in point, Mike
Warot, a reader I knew for insightful
comments and fun ideas (for example, see
"It's All Like...What?" on page 16). Mike's
experience is a good sample of what
must be happening in countless shops,
even though each is different. Now, here's
Mike's description of "what he's using":
I'm a one-man IT staff in what
used to be a Windows shop.
Today I have two machines on
my desk. The one I just let run is
Ubuntu. It just runs, 24x7, and
it's there when I need it.
The change came once it became
apparent that we were going to
have to put our Windows servers
behind a firewall. I decided to
use Linux to make a firewall. I
used Red Hat and EBtables to
create a transparent bridge to
avoid having to re-address our
servers and let everything keep
its public IP address. This was
nice, because it still wasn't neces¬
sary to have a firewall, it was just
an extra precaution at the time.
That worked well for about a year,
until I got worried I wouldn't be
able to restart it. That's when a
friend told me about IPcop in his
work with nonprofits. IPcop is a
very easy to configure and main¬
tain Linux-based firewall, which
does a great job in almost all cir¬
cumstances. I used IPcop for a year
or so, until problems with multiple
Internet connections forced me to
seek a better solution.
At the same time I put in the
IPcop box, I learned (eventually)
two very important facts about
Windows 2000 Servers and the
Internet. First, if your domain
controllers have multiple subnets
from which to choose, they will
get confused and not be able to
find each other (meaning users
might not be able to log in).
And second, if you followed
common sense and used your
real domain name for your
Windows domain name, you
were FUBAR, because active
directory then puts all of your
local addresses in the DNS, and
you can't remove them (or the
domain stops working again).
This required another Linux box,
for DNS services to the world.
It's running Fedora Core 5, but
I'm about to replace it, because
I don't know how to update the
DNS to fix the current exploit.
It'll get replaced with a VMware
virtual machine running Ubuntu
(more about VMware below). I
now have an Ubuntu box with
iptables (or ipchains, I always
forget), which connects us to
our three Internet connections.
With the proliferation of servers,
VMware's offer of the free
VMware Server was a godsend.
And, I've since learned that Linux
makes a far better host than
Windows does. So, I've got some
of my VMware servers running
on Ubuntu, with Windows and
other things inside them.
Ubuntu has made it pretty easy
to set up a new machine—not
that Red Hat was very hard.
But with apt-get, installation
of almost any program is trivial.
I use an editor called joe to do
editing when I don't have the
X Window System set up (on
some of the older servers), and
it's just sudo apt-get install
joe, and I'm up and running.
I'm not a guru, but I've learned
enough over the years to get
around. Linux offers a wider set
of tools than Windows ever
could. Bottom line: Linux is
amazing, and it's getting better
all the time.
— DOC SEARLS
'Finalist Best Management Tool'
Programmable Linux Based
Console Server Solutions
Service Processor Network UPS Tools
Management Secure Tunneling
DRAG Port Forwarding
iLO Nagios Checks
ALOM Embedded IPMI
RSA Flexible Pinouts
opcngcor.com
COLUMNS
AT THE FORGE
Unobtrusive JavaScript
Remove JavaScript event handlers from HTML files using Prototype
and Lowpro.
REUVEN M. LERNER
JavaScript has gone through a number of changes
in the past few years. Implementations have
become faster, more standardized and more stable.
The development and growth of open-source
JavaScript libraries, such as Prototype and Dojo, has
helped mask many of the remaining differences
between JavaScript implementations, such as with
AJAX and event handling. The final change has
occurred in the minds of developers (including
myself), who now approach JavaScript as a serious
application development language, rather than as a
toy for highlighting images or doing simple effects.
Most JavaScript is executed not when it is initially
read into a browser window, but rather when a
particular event takes place. The easiest, and most
common, way to assign event handlers is inside the
HTML itself. For example, we can create a submit
button for an HTML form as follows:
With the onclick handler in place, the button
now opens a JavaScript alert box (saying "hello").
Moreover, because our event-handler definition
returns false, the form will not be submitted.
Of course, we don't have to put our JavaScript
literally in the event handler. We could define a
function somewhere else—in the document's
or perhaps in an external JavaScript file altogether:
Unobtrusive JavaScript
Unobtrusive JavaScript
A paragraph of text.
A hyperlink
to The New York Times.
Now, none of this is new. But, there are
problems associated with setting event handlers
in "on_" attributes. For one, it becomes difficult
to assign more than one handler to the same
event on an object.
A second and more significant reason is that our
HTML becomes full of JavaScript. Until a few years
ago, it wasn't unusual for HTML to be mixed in with
code and style information as well, but the growth
of strictly separated MVC frameworks have removed
most code from the HTML, and style information
now is put in external CSS files.
A growing movement during the past few
years has pushed for "unobtrusive JavaScript".
Proponents of unobtrusive JavaScript argue that
by placing JavaScript in a separate file and by
defining event handlers in a separate file, the code
becomes easier to read and understand and is
cached by the browser. By using JavaScript unob¬
trusively, we also have the opportunity to make
our HTML pages degrade gracefully, continuing to
work with browsers that don't support JavaScript.
18 | October 2008 www.linuxjournal.com
$('hyperlink').onclick = show_x_and_y;
Notice that our assignment is to show_x_and_y
(that is, the name of a function), rather than to
show_x_and_y() (that is, the result of executing the
function). This is a particularly useful technique if
we want to assign the same function to handle
multiple events.
We can handle a number of different events. For
example, the onmouseover and onmouseout events
let us execute a function based on when the mouse
This month, we look at unobtrusive JavaScript
and the unobtrusive approach to defining functions
and event handlers. We also examine the Lowpro
library that works with the popular Prototype
JavaScript library, allowing us to write JavaScript
that is unobtrusive, clean and easy to read.
Observing Events
Above, I showed how to assign a piece of JavaScript
(called "do_something") to an event on a particular
HTML element. A fuller version of this HTML form,
as well as some more content and tags, is shown
in Listing 1 (test.html). This file contains a simple
hyperlink, as well as our form.
I've already discussed how to handle an onclick
event by setting the onclick attribute. However,
there are at least two other methods for setting this
event handler. One is to set the onclick attribute
through JavaScript, treating onclick as a property of
the DOM element associated with the hyperlink or
button. Using Prototype's $() function, we can write:
$('hyperlink 1 ).onclick =
functionO { alert(' clicked!'); return false; }
Notice how the event handler is an anonymous
function, similar to "lambda" in Ruby and Python
or an anonymous subroutine in Perl. The event¬
handling function can take an optional argument,
whose value will be an event object. For example:
$('hyperlink').onclick =
function(event) { alert(event); return false; }
With this alternate code in place, the alert (in
Firefox, at least) indicates that the event was an
"object MouseEvent". This object, like all objects in
JavaScript, then has a number of properties we can
query. For example, the pageX and pageY proper¬
ties indicate the X and Y coordinates of the mouse
cursor when the event took place. We can see these
by specifying the following:
$('hyperlink').onclick =
function(event) { alert(event.pageX + ", " +
event.pageY); return false; }
Each click on the link will give a slightly different
result, depending on the coordinates of the mouse
cursor at the time of the click.
Of course, we also can define non-anonymous
functions as our event handlers:
function show_x_and_y(event) {
alert(event.pageX + ", " + event.pageY); return false;
}
Listing 2. test-2.html, with Event Flandlers Defined in