As an inhabitant of the Great Outdoors (Gisborne, New Zealand, aka “First City of the Sun”), I most vigorously applaud Doc Searls' insightful debunk of that facile phenomenon, Facebook [see Doc's “Waving Goodbye to Facebook” in the August 2010 issue]. Zuckerberg's only claim to glory, that I can see, is that he used the Internet to organise the mighty sales predator and manipulate the great American unwashed into making him a billionaire at age 26. The idea that this young man and his cohort should “seize control of the Internet” is enough to make hair grow in unspeakable places. Let the kids go to the mall if they wish. Me? I'll make sail for discovery bay.
It is my pleasure to express the gratitude felt to Mr Searls and his ilk
for their care and compassion in steering true through inevitable
I would like to see an article that evaluates which distro has the
easiest UDEV rules to work with. I have spent hours trying to write a rule on
openSUSE and have not gotten the desired results. Is Ubuntu or Fedora easier
to work with?
Honestly, UDEV rules are confusing regardless of the distribution. Perhaps it's something we should cover. Thanks for sharing your misery!—Ed.
I just read Doc Searls' EOF “3G Hell” in the October 2010 issue, and I'm shocked—but, not about the national-fenced data access. I live in Europe; it's a well-known nightmare and quite a long matter. Let's just say that it's kind of an indirect battle and not strictly Linux-related.
The shocking bit was to learn that not even Linux Journal's Senior Editor is completely in control of what's running on his (Linux-based) phone (that is, the Twitter client). I thought these kind of things affected only ignorant and mortal users like myself.
That is a kind of battle much more direct and related to the Linux community.
Nobody else has an interest in giving users that kind of control (data
access “accidents” are worth millions).
Moreover, I think it would be healthy for a community where
real-men-use-vim-and-a-zippo-lighter (aka GUIs-are-for-fussies) start
thinking about simpler ways to give that kind of low-level control—say, an
IASADCFGS button (as in “I'm abroad, shut all data communication for god's
Doc Searls replies: That's a great idea, Daniele. I still think opening up mobile data markets is a worthy effort. The Internet is a rising tide that lifts all economic boats. I believe mobile-phone companies can make a lot more money in the open market than by punishing user mistakes in their closed ones.
As always, Linux Journal is great. I've read every issue since the earliest issues, and I can't thank you enough for the articles. I was very pleased to find an article on sc [see Serge Hallyn's “sc: the Venerable Spreadsheet Calculator” in the October 2010 issue]. There was an article in 1998 that used sc as an example of free software that is easy to embed software in [see “Perl Embedding” by John Quillan in the November 1998 issue]. I used sc and Linux to do huge spreadsheet calculations for a Master's degree project. The other operating systems and spreadsheets kept running out of memory and resources. I use sc to make and review hundreds of spreadsheets, sometimes in only a few hours. Here's a code snippet of mine:
psc -d , < /.w/Top100Stocks.csv > /.w/Top100Stocks.sc echo "format A 8 0 0" >> /.w/Top100Stocks.sc echo "format C 7 0 0" >> /.w/Top100Stocks.sc echo "format G 12 0 0" >> /.w/Top100Stocks.sc echo "leftstring A1 = \"q\"" >> /.w/Top100Stocks.sc echo "leftstring B1 = \"Corporation\"" >> /.w/Top100Stocks.sc echo "leftstring C1 = \"Alpha\"" >> /.w/Top100Stocks.sc echo "leftstring D1 = \"Last\"" >> /.w/Top100Stocks.sc echo "leftstring E1 = \"RStr%\"" >> /.w/Top100Stocks.sc echo "leftstring F1 = \"HVol%\"" >> /.w/Top100Stocks.sc echo "leftstring G1 = \"AvgVol\"" >> /.w/Top100Stocks.sc echo "leftstring H1 = \"YTD%\"" >> /.w/Top100Stocks.sc echo "leftstring I1 = \"52WH\"" >> /.w/Top100Stocks.sc echo "leftstring J1 = \"52WL\"" >> /.w/Top100Stocks.sc ...
Now, this brings me to the main reason I'm typing this up. The article on sc
included some Python code, which is great and very useful. But, psc can be
used to put a .csv into .sc form (as shown above)—psc comes with sc.
Just do man psc for more information. Again, thanks
for the great article; obviously,
sc is one of my favorite apps. I remember kibbitzing with members of the
local DCLUG, and they very much agreed it was one of their favorites too.
Brian G. Powell
When it comes to Linux, although I've been using it only for about five years
(I'm 14), I'm already sure of my taste in minimalism when it comes to
computing. I'm a firm believer in minimalism, with Tiny-core Linux as my
primary distribution. I seem to find any other OS wildly bloated. I would be
interested to see more written about it in a world where everything in
computers seems to be getting ever more complicated. There is still
something to be said for keeping it simple.
Indeed, there is something to be said for keeping it simple! For many of us a command line is all we need. On many days, I manage my network remotely from my Droid. If you ever meet Kyle Rankin, you'll have to ask him about fixing his data center from the top of a ski slope. Anyway, thanks for the reminder to cover the small things. We'll do our best.—Ed.
I'm writing to say that I very much enjoyed Kyle Rankin's October 2010 Hack and / column “Take Mutt for a Walk”. I've looked at using mutt many times in the past, but I just couldn't overcome the easiness of continuing to use Icedove. Kyle's article finally gave me the kick in the pants I needed to force myself to use mutt seriously—particularly the listing that showed examples of send hooks and reply hooks, so a huge thank you to him for that!
I would like to point out to Kyle that he is partially incorrect in stating that mutt requires a local mail server to function. Recent versions of mutt include basic MTA capabilities, allowing it to speak directly with a remote mail server (smarthost). This is, in fact, how I am using mutt currently. To use a remote SMTP server, simply set the smtp_url variable like so:
Of course, the URL will need to be modified appropriately for different
environments. Hopefully, this information will be useful to my fellow
Kyle Rankin replies: Wow, did you hear that Mr Childers? Mutt has direct SMTP support now. They must have slipped that in when I wasn't paying attention. Thanks for that tip; I'm sure other beginning mutt users will appreciate not having to set up a local mail server just to try it out.
Regarding Dave Taylor's shell column “Function Return Codes and Daylight Calculations” in the October 2010 issue, the article compares the current hour and minute with the local sunset time and uses three tests for this. And, Dave calls it “kind of neat” to boot.
That's not very neat. To compare two times, you really should convert to the lowest unit and do one test. So here, you would do:
currenttime=$(( $hour * 60 + $min )) sunrisetime=$(( $srh * 60 + $srm )) sunsettime=$(( $ssh * 60 + $ssm ))
And the test is:
if [ $currenttime -ge $ sunrisetime -a $currenttime ↪-le $sunsettime ]; then # daytime ... fi
Isn't that easier to understand and more maintainable?
You even could replace the sunrise and sunset vars with their expressions,
but that would hamper readability.
Remember, people don't want neat. They want readable.
Dave Taylor replies: Thanks for your note, Fred. One thing I've found that is true of shell scripts is that you always can write them more succinctly and tweak algorithms to be shorter or more efficient, but at some point, you easily can end up spending more time tweaking a script than the time you'd be saving by it existing in the first place! Oh, and I'll argue the neat (that is, elegant) versus readable topic, but that's another thing entirely.
I am the pain-in-the-neck subscriber who is always asking for more articles for beginners. If there were three levels of Linux users—Beginner, Intermediate and Advanced—I would characterize myself as between Beginner and Intermediate but closer to Beginner. With that in mind, I have a couple requests for articles (information) in the magazine.
I am a Netflix subscriber (for almost ten years now). However, because I use the Ubuntu Linux operating system on my computer (v. 10.04), I cannot watch Netflix on Demand on it. Netflix evidently has no concrete plans to allow this.
Has anyone figured out a way to watch Netflix movies on his/her Ubuntu computer? And, if so, would that person be willing to write an article giving step-by-step instructions suitable for someone like me?
My wife and I do not use cell phones very much; consequently, we have Virgin Mobile pay-as-you-go plans. Virgin Mobile offers a pay-as-you-go Internet access, which we would like very much to have. You can buy it on an as-needed basis, so we would buy it to use when we travel.
Needless to say, because our travel computers are also operated via Ubuntu Linux, we are locked out of that too. Virgin Mobile folks say that Linux computer access is coming “in the future”, but they've been making that vague promise for more than a year now.
Have any readers figured out a way to operate their Linux computer on this Virgin Mobile network, and would they be willing to write an article, again with step-by-step instructions that I could understand?
The step-by-step instructions I request mean just that. They really would have to
be step by step, assuming I know next to nothing (which is really
I think articles like this (and these two specifically) would be of great
interest to many of your readers, and they certainly would be to me.
Lawrence H. Bulk
Thanks for the article ideas. Your frustrations are not yours alone. Although Netflix works on embedded-Linux devices, there seems to be no support for actual Linux users. Hopefully, we'll see that change someday. As to your Virgin Mobile problem, I usually keep a copy of Windows XP in a VM (behind a NAT on my laptop), so I can authenticate to those Windows-only sites and then use the service on Ubuntu. Good luck!—Ed.
I am regular reader of Linux Journal and wanted to provide feedback (some a bit overdue). I very much enjoyed the article that Rick Rogers wrote in the September 2010 issue on mobile development. I followed up with a question or two related to iPhone development and he was quite helpful. Please consider including other articles on mobile development in Linux when planning future issues of Linux Journal (from Rick).
Also, this is a bit overdue, but I also really enjoyed the Amateur Radio articles in the January 2010 issue. Because of this special feature, I purchased two copies off the newsstand and gave the second issue to another Ham radio operator. Possibly you could carry this theme every 14–18 months?
Like so many others, I vote with my pocketbook. Because
LJ has issues such
as the January issue featuring Amateur Radio, I purchased some of the
special CDs that you offered from the LJ store (earlier this year).
We've gotten lots of good feedback on the Amateur Radio issue, so I wouldn't be surprised to see the theme come up again in one form or another. Thanks for the positive words!—Ed.
I really liked Kyle Rankin's “Taking Mutt for a Walk” article
(October 2010 issue), and
I tried it out myself (with the configuration printed). However, upon
starting mutt, I got the message “Error in /home/ian/.muttrc, line 17:
alternates: unknown variable” (though mutt started anyway). A quick Google
told me this was only with Debian and derivatives (I'm running Ubuntu) and
to read /usr/share/doc/mutt/NEWS.Debian.gz. It seems that (in the
repository version anyway), “alternates” has been changed from a variable
to an option. Changing the line set
alternates ((foo|bar)@example.org) fixes it. Anyway, thanks for a great
Kyle Rankin replies: Thanks for the detective work. I admit that my config has been in place for quite some time—probably from before that option was changed.
Practical Task Scheduling Deployment
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
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- The Firebird Project's Firebird Relational Database
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- My +1 Sword of Productivity
- SUSE LLC's SUSE Manager
- Managing Linux Using Puppet
- Non-Linux FOSS: Caffeine!
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- Parsing an RSS News Feed with a Bash Script
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- Doing for User Space What We Did for Kernel Space
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