bc: an arbitrary precision numeric processing language

published on Thu Oct 11 05:00:17 2007 in packages-news

Article submitted by Markus Grunwald. We are running out of articles! Please help DPOTD and submit good articles about software you like!

Debian currently offers 84 packages that mention “calculator” (apt-cache search calculator | wc -l). An alternative to the more eye-candy-heavy calculators on offer is bc. bc has no fancy GUI, but is instead console-based and allows a simple mathematical language, making it really fast and programmable.

Everyday use

By default, bc behaves quite unhelpfully: zero digits and no predefined functions such as sin, cos, log etc. You can remedy this by calling bc with the -l parameter, so that it uses the standard math library. Instead of always typing “bc -l”, you can use the fact that bc reads the environment variable BC_ENV_ARGS. So for all the bash guys: add an export BC_ENV_ARGS=-l to your ~/.bashrc.

Let’s try the everyday use first: some simple calculations. Just type your expression and complete it with the enter key:

$ bc
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.
850*77.1        <enter>
65535.0

That’s better than Excel 2007! And all of you terminal people will get this answer quicker than every KDE or GNOME user who starts their GUI calculator.

Custom scale and functions

The scale (total number of decimal digits after the decimal point) of bc’s results is 20 when you run it with “-l”, but you can set it up to a maximum of 2147483647. So to get a quite good estimate of π, just type:

scale=200  <enter>
4*a(1)     <enter>
3.141592653589793238462643383279502884197169399375105820974944592307
81640628620899862803482534211706798214808651328230664709384460955058
223172535940812848111745028410270193852110555964462294895493038196

Impressive. But what’s “a(1)”? bc uses very short names for the trigonometric functions. a(x) is the arctangent of x. For all of you who like longer names, you can define your own function and write it in a file. Add this file to your BC_ENV_ARGS and it will be read every time you start bc. The best thing to do is to get extensions.bc from http://x-bc.sourceforge.net/extensions_bc.html.

My BC_ENV_ARGS looks like this:

$ echo $BC_ENV_ARGS
-q -l /home/gru/.bc/extensions.bc

extensions.bc defines several functions by the names people normally know them, for example:

define sin(x)
{
        return (s(x))
}

This way, you can define your own function. I have to convert ratios to decibel and use this quite often:

define db(x,y)
{
        return 20*log(x/y);
}

Converting to other bases

bc can convert from and to arbitrary number bases. Say you want to convert from decimal to hexadecimal. Set the output base obase to 16:

obase=16 <enter>
10
A

And of course, you can calculate with these numbers too:

10/7
1.6DB6DB6DB6DB6DB6B

You can set the input base too:

ibase=16 <enter>
A/2
5
sin(AFFE) <enter>
-.B1F4021654E454E72

I leave the interpretation to the user ;)

Use in shell scripts

Bash is a nice shell, but when it comes to complex calculations $(()) won’t do the job. bc can help:

$ a=$( echo "l(1024)/l(2)" | bc )
$ echo $a
10

Conclusion

I searched quite long for the ideal calculator for me. After trying several GUI calculators, I didn’t find mine. Then I tried bc and it’s perfect for me. I hope you will like it too.

bc is available from Oldstable to Unstable in Debian and Ubuntu Dapper, Edgy, Feisty and Gutsy.

Links

• Homepage
• Online manual
• extensions.bc
• Wikipedia entry for bc programming language
• X-Bc – a graphical user interface to Bc

2nd Colombian Mini-DebConf, Medellin (Antioquia), October 13th and 14th

contributed by andremachado, published on Tue Oct 9 00:17:36 2007 in event-announce

The 2nd Colombian Mini-DebConf will be held at Medellín (Antioquia), on October 13th and 14th.

It will be a space where the people of the Debian community of Colombia could meet together and work around the project.

There will be a Key Signing Party, talks, packaging workshops and several other debian-collaboration activities, and of course, some free-fun time.

All the updated info (in Spanish) is at the wiki page.

hpodder: a podcast client that just works.

published on Sun Oct 7 05:00:12 2007 in packages-news

Article submitted by Matt Clare. We are running out of articles! Please help DPOTD and submit good articles about software you like!

Synopsis

hpodder is a command-line podcast client that just works. The command arguments are simple to master and allow for flexibility in downloading.

In depth

So you’ve have been desperate for a podcast client that rivals the ease and efficiency of iTunes (but have found Linux clients wanting) then hpodder may be the answer to your quest. Having found other clients to be a little jack-of-all-trades for your needs or else, just plain buggy, hpodder is a breath of fresh air.

Once installed, typing hpodder in the terminal will get things under way. The initial run will allow you to make a directory for access your podcasts from and give you the option to subscribe to the sample feeds. If you pass and just want to get onto subscribing your own feeds type:

$ hpodder add http://yourfavouritesite.com/podcastfeed.xml

This will add the feed to the hpodder database and assign an ID that allows for easy specification and manipulation of a feed later on. Hpodder will handle any valid podcast feed, even if it is not the traditional .xml address —including feeds extracted from an OPML export of iTunes podcasts. Once you have your list of podcasts you wish to download, simply type:

$ hpodder update
$ hpodder download

Or, if you want to make life easy:

$ hpodder fetch

As this does effectively the same job as the two commands combined. If you are using hpodder to listen to a podcast that you have perhaps been listening to on another machine, and want to download only the most recent episode, you can do this by typing:

#000; padding:10px">

#000; padding:10px">
$ hpodder catchup
$ hpodder fetch

If you want to only download or update specific podcasts, you can do so by specifying the podcast’s ID after the command (update, download, fetch, catchup). If you want to delete a podcast type:

#000; padding:10px">

#000; padding:10px">
$ hpodder rm ID

Where ID is the podcast’s ID number (else you risk deleting them all!).

Downloading the actual episode of your podcast is handled by cURL and is fast, efficient and if interrupted for whatever reason, can be picked up later on without having to start the download from the beginning.

If you want to make hpodder fetch on a regular basis, you can add it to your cron jobs and set it to run as frequently as you like.

If you want a full list of the commands and more subtle features available to hpodder users you can download the manual in PDF format, or read it online.

Any downsides?

The only real downside is that you need to use a second program to listen to your downloaded podcast episodes, but then most people have a favourite media player (kaffeine, mplayer, totem, vlc et al) that they use given the chance.

hpodder is available in Debian since Etch, and in Ubuntu since Feisty

weather: check weather conditions and forecasts on the command line

published on Thu Oct 4 05:00:08 2007 in packages-news

Article submitted by Dann Frazier. We are running out of articles ! Please help DPOTD and submit good articles about software you like !

weather, provided by the weather-util package, is a simple command line tool that lets you check current conditions and forecasts. It uses METAR data that it fetches from the the National Oceanic and Atmospheric Administration and forecasts from the National Weather Service. The documentation says it’s limited to providing information for the United States, but in fact, METAR data is available for stations all around the world. The forecast won’t be available, though.

Many locations are already pre-configured in the package’s /etc/weatherrc. If your location is already defined, you only need to look up the alias to begin using it. For example, /etc/weatherrc provides the following entry for Albuquerque, New Mexico:

[ABQ]
City = Albuquerque
ID = KABQ
St = NM

The alias for Albuquerque is ‘ABQ’. Therefore, weather ABQ will show you the current conditions for Albuquerque:

$ weather ABQ
Current conditions at Albuquerque International Airport (KABQ)
Last updated Sep 26, 2007 - 04:56 PM EDT / 2007.09.26 2056 UTC
  Wind: from the ESE (120 degrees) at 3 MPH (3 KT)
  Sky conditions: mostly clear
  Temperature: 77.0 F (25.0 C)
  Relative Humidity: 15%

weather -f ABQ will include a local forecast:

$ weather -f ABQ
Current conditions at Albuquerque International Airport (KABQ)
Last updated Sep 26, 2007 - 04:56 PM EDT / 2007.09.26 2056 UTC
  Wind: from the ESE (120 degrees) at 3 MPH (3 KT)
  Sky conditions: mostly clear
  Temperature: 77.0 F (25.0 C)
  Relative Humidity: 15%
City Forecast for Albuquerque, NM
Issued Wednesday afternoon - Sep 26, 2007
  Wednesday night... Low 52, 0% chance of precipitation.
  Thursday... Sunny, high 81, 0% chance of precipitation.
  Thursday night... Low 54, 5% chance of precipitation.
  Friday... Partly cloudy, high 80.
  Friday night... Low 56.

You can add new locations to this file directly, or to per-user ~/.weatherrc files. You can also define a default location by adding a stanza with an alias named “default”. For example, here’s the contents of my ~/.weatherrc file:

[default]
City = denver
Forecast = True
ID = KFNL
St = CO

City and St (state) are used for obtaining forecasts, while ID is used for retrieving current conditions. I use this configuration to tell weather to retrieve forecasts from Denver, CO but to use a station that is closer to me for obtaining current conditions. Note that if you do not specify a location and have no alias named ‘default’, weather will fall back to a hard-coded default of Raleigh, NC.

Knowing what information weather uses to obtain the data you request is important when defining your own configurations. For example, say I want to know the current conditions for Lubbock, TX and I run the following command:

$ weather -o --city=Lubbock --st=TX
Current conditions at Fort Collins-Loveland Municipal Airport (KFNL)
Last updated Sep 26, 2007 - 05:55 PM EDT / 2007.09.26 2155 UTC
  Wind: from the ENE (070 degrees) at 5 MPH (4 KT)
  Sky conditions: clear
  Temperature: 71 F (22 C)
  Relative Humidity: 23%

(The -o tells weather to omit the forecast). Notice that weather gave me the current conditions for my ‘default’ alias, not for Lubbock. This is because weather looks up current conditions by station ID, not by city/state. If I pass the station ID instead, I’ll get the information I was looking for:

$ weather -o --id=KLBB
Current conditions at Lubbock International Airport (KLBB)
Last updated Sep 26, 2007 - 05:53 PM EDT / 2007.09.26 2153 UTC
  Wind: from the S (170 degrees) at 9 MPH (8 KT) gusting to 18 MPH (16 KT)
  Sky conditions: mostly cloudy
  Weather: Cumulonimbus clouds, towering cumulus clouds observed
  Temperature: 86.0 F (30.0 C)
  Relative Humidity: 38%

Being a command-line tool, weather lends itself to various automatic processes. For example, you might want to cancel your weekly bicycle pub crawl if the forecast shows a high chance of rain:

$ cat /etc/cron.weekly/pub-reminder
#!/bin/sh

set -e

if weather -f | egrep -q '(100)|([5-9][0-9])% chance of precipitation'; then
 mailx -s 'Cancellation' $PUBCRAWLEES < ~/pub-crawl-cancelled
else
 mailx -s 'Get on your bike' $PUBCRAWLEES < ~/pub-crawl-is-a-go
fi

Of course, I’d just recommend a rain jacket.

weather is provided by the weather-util package and is available in Debian ‘etch’, testing and unstable, and Ubuntu ‘edgy’, ‘feisty’ and ‘gutsy’.

DebConf maintenance

published on Sun Sep 30 21:31:00 2007 in debconf-news

In the last few days we (as in DebConf admins Steve Gran, Mark Hymers and myself) have been doing some DebConf maintenance work.

Some time ago one of DebConf’s permanent sponsors, ByteMark sponsored a new machine, krabappel, which we use as a replacement for the older machine we have from them, cmburns. It was neccessary, as good old cmburns had a lot of stuff running and so was always pretty loaded. Imagine it running most of our websites, main mail and dns server and then also having 4 vserver instances on it. Those vserver itself where also running things that do use some resources, like our wiki and the main DebConf7 site, the PentaBarf test-host and our LedgerSMB instance.

While it was long decided to move stuff our - we just had to find time to do it. This weekend seems to be it, everything is migrated except cmburns itself, as that needs a fix in the reverse dns entries for the new /28 we got.

We are using xen-tools to make installation of new images easy. For that I wrote a script that is used as a role script, automating all that various setup tasks that one can automate easily. Which means that it takes about 5 minutes to get a complete new XEN domain up and running. (Add some minutes to add it to nagios2, munin, our mail setup and to sync the userdatabase.)

Mark and Steve also did another migration: gallery.debconf.org is now using gallery2. Still needs a nice layout designed looking similar to our normal DebConf website, but that shouldn’t be too hard to get. While they have been on it they also integrated gallery.debian.net, so that it is back up again. Feel free to use both of them!

gallery.debconf.org offers space for all DebConf related pictures, be it the main yearly DebConf (and related) or regional DebConfs, like the one planned for Panama soon.

gallery.debian.net is a place where pictures from all Debian related events/parties/whatever can be put. Basically - whenever people working on Debian meet (like a BSP, a work meeting, etc) - feel free to put pictures up there. Just put them into a folder matching the year it happened in… Basic goal is to get a huge set of pictures from people involved in Debian.

Debaday needs your help (yeah, seriously)

published on Thu Sep 27 08:25:30 2007 in packages-news

Debaday didn’t publish anything last Sunday and Wednesday. It was simply because we have nothing to publish. :(

Due to the vacations of two editors (out of three), we were slower than usually to reply to submissions. But it’s not like we have received a lot of submissions recently.

We really need *your* help! Send us an quality article. See Contribute page for details. If you always wanted send us an article, but you did not know what to write about, here you have a small list of application people have requested or we think could be interesting to feature:

• screenkast
• approx
• email-reminder
• deborphan / debfoster
• gaupol
• psi
• kid3
• wget (yeah, surely there is people who does not know this!)
• httptunnel
• dctrl-tools
• strigi
• any game you like

If you are a user of any of this program and think it deserves be featured in debaday, send us an entry! :)

Also, we really need a fourth editor. The task includes replying to submissions, suggesting improvements, doing some minor editing and HTML formatting. You don’t need to be a native english speaker (the 3 editors are non-natives currently). And you get to read all entries before they are published, so you can show off with cool apps that nobody knows! If you can dedicate a little time on a regular basis to this (about 1 hour per week would be awesome), and think you won’t become crazy after working with ana, lucas and Tincho, just contact us!

GPRename: GTK2-Perl Batch Renamer

published on Wed Sep 19 05:00:59 2007 in packages-news

Article submitted by Johan Spee. We are running out of articles ! Please help DPOTD and submit good articles about software you like !

GPRename is a complete batch renamer for files and directories coded in GTK2 and Perl.

GPRename has been around since 2001, is quite stable and still very much alive today. At the start of 2007, it was ported from the deprecated GTK-Perl to the new GTK2-Perl and in mid 2007 the new 2.4 release is now GPL-3. The package was recently added to the Debian repositories (currently available in ‘testing’ and ‘unstable’) and can be used in many languages.

The program is lightweight and easy to use, yet supports a very complete set of features. In this respect it is comparable to renamers of more fame such as Konqueror’s KRename (KDE) or Thunar’s Bulk Rename (XFCE). GNOME does not have an official renamer but GPRename can easily fill that void. With a simple ‘action’ it can be integrated into Nautilus, the GNOME’s file manager (the prefab action is available). With the action installed any directory in Nautilus can directly be opened in GPRename through the right-click context menu.

Even relatively inexperienced Linux users will have little trouble with the graphical interface, which in many ways resembles that of Nautilus and other file managers. The left panel shows a directory-tree for the usual point-and-shoot navigation. In the panel next to it files or directories (separate tabs) that are to be renamed can be selected. A preview of the modified names is also shown here, either after clicking the ‘preview’ button or automatically. Other useful automated options include:

• Convert double spaces to single spaces.
• Trim leading and/or trailing spaces.
• Add leading zeros to numbers.

The bottom panel has four tabs, one for every basic rename function. The screenshots are quite self-explanatory:

Case change (UPPER, First Letter, lower)

Insert or delete text at a given position

Replace text (options: ‘case sensitive’ and ‘regular expressions’)

Rename using incremental numbers (pic-01.jpg, pic-02.jpg etc.)

Don’t hesitate to give it a try, since there’s always the very reassuring ‘undo’ button. You never know.

GPRename is available in Debian testing and unstable, and will also be available in Ubuntu Gutsy.

newsbeuter: RSS feed reader for the text console

published on Sun Sep 16 05:00:11 2007 in packages-news

Article submitted by Andreas Krennmair. We are running out of articles ! Please help DPOTD and submit good articles about software you like !

RSS is a set of XML-based formats to describe articles (including title, link to the original article, description, etc.) which are usually transported via the HTTP protocol. These days, the majority of blogs and news websites provide RSS feeds. In order to read these feeds in a useful way, special programs, called RSS feed readers or RSS aggregators, can be used.

Newsbeuter is an RSS feedreader for the text console. It comes with a user interface in the style of such popular text tools such as mutt and slrn, and aims to be the text-mode RSS feedreader with the most features, providing the greatest flexibility for its users.

Starting with newsbeuter

After installing newsbeuter with a simple aptitude install newsbeuter (currently in Debian unstable, only), you can run newsbeuter for the first time, and is presented with the following message:

Error: no URLs configured. Please fill the file /home/ak/.newsbeuter/urls with RSS feed URLs or import an OPML file.

newsbeuter 0.6
usage: ./newsbeuter [-i <file>|-e] [-u <urlfile>] [-c <cachefile>] [-h]
        -r              refresh feeds on start
        -e              export OPML feed to stdout
        -i <file>       import OPML file
        -u <urlfile>    read RSS feed URLs from <urlfile>
        -c <cachefile>  use <cachefile> as cache file
        -C <configfile> read configuration from <configfile>
        -v              clean up cache thoroughly
        -h              this help

This means that newsbeuter needs to be configured with the RSS feed URLs that you want to read. This can either by achieved by manually filling
~/.newsbeuter/urls with RSS feed URLs (one by line), or by importing an OPML file by running newsbeuter -i blogroll.opml. OPML is a XML-based format for describing outlines, and is in wide use to import and export lists of RSS subscriptons between RSS feedreaders.

Newsbeuter can be configured via its configuration file ~/.newsbeuter/config. A wide range of properties and behaviour can be configured, so it’s wise to have a look into the provided documentation.

A reasonable configuration to start with is the following setup. The manpage lists all available configuration options, so there’s a lot to experiment with.

# This is an example configuration file for newsbeuter
# save this as ~/.newsbeuter/config

auto-reload yes       # automatically start a "reload all" thread at a defined interval
reload-time 30        # reload all feeds every 30 minutes
confirm-exit yes      # always ask the user whether he really wants to quit

Advanced Features

What makes newsbeuter so interesting are the advanced features it comes with. For previous users of SnowNews (another console-based RSS feedreader), newsbeuter supports snownews extensions, which are easy to develop and of which a huge collection is readily available.

Newsbeuter also comes with support for podcasts. Newsbeuter contains functionality to help collect podcast download URLs (either automatically or manually), which can then be downloaded with a separate tool called “podbeuter”.

Another very interesting feature is the internal filter language. It’s a generic expression language that makes it easy to define complex search criterias, which cannot only be used both for searching for feeds and articles, but also for defining rules for ignoring certain articles (think of killfiles for RSS feeds), or configuring “meta feeds”, feeds that contain only articles from other feeds which match a filter expression. The documentation comes with plenty of examples for these use cases.

Other features supported by newsbeuter are a flexible categorization functionality based on tags (every RSS feed can be tagged with keywords, and the displaying of RSS feeds can be filtered by tags), notifications about new articles via external programs or directly to a GNU screen session, free configurability of key bindings and colors, and an internal command line.

Screenshots

The typical feedlist of newsbeuter, giving the user an overview over configured feeds and the number of downloaded and unread articles per feed:

Newsbeuter renders the HTML that is contained in article descriptions, and lists all links that are contained in the article (these links can even be opened with a simple keypress in a freely configurable web browser):

Colors can be freely configured, as demonstrated by this screenshot:

Internationalization (I18N) and localization (L10N) are important in the newsbeuter project. Newsbeuter can perfectly handle Unicode characters, and its user interface is currently available in English (default), German, Italian, French and Russian. The screenshot shows a Russian newsbeuter, displaying a Japanese RSS feed:

Comparison with other RSS Feedreaders

A few other text-mode RSS feedreaders beside newsbeuter exist. The most prominent ones are Snownews and raggle. Both Snownews and raggle have in common that they are no longer under active development. Snownews itself is hard to maintain and extend, and raggle is relatively slow (even on new, fast computers), because it is purely implemented in the Ruby scripting language. Especially Snownews lacks a lot of features compared to newsbeuter, such as support for the Atom XML format and HTTPS support.

One goal of newsbeuter development was to build a feed reader that does not only fix the deficiencies of the existing tools and integrate all the useful features, but that is also easily extensible. This goal has been achieved, and now development is aiming at more advanced features: future releases will contain a flexible and extensible bookmarking support, improved support for notification frameworks such as Growl, and synchronization with web RSS feed readers such as Bloglines.

More Information

• Newsbeuter website
• Online documentation
• Debian package

Since newsbeuter is relatively new (development started in November 2006, the first Debian package entered unstable in February 2007), it is only available in unstable and testing (in a completely outdated version). It will be available in Ubuntu Gutsy, but the version is outdated already as well.

Dzongkha Debian Linux updated for the Bhutanese people

contributed by andremachado, published on Fri Sep 14 13:19:24 2007 in news

At August 28th 2007, the Research Division of Department of Information and Technology (DIT) of the Bhutanese Ministry of Information and Communications updated its Dzongkha Debian Linux from the previous Dzongkha Linux 1.0 launched in June 2006. The installer is based on Debian Linux 4.0 Etch while the LiveCD is based on Morphix Linux.

According to Pema Geyleg, head developer of the Dzongkha Debian Linux, the launch of the Dzongkha Debian Linux marks Bhutan’s move towards free and open source software. Linux is a free operating system and we customised the Debian Linux according to the need of our Dzongkha users, he said. Since Debian Linux is recognised worldwide, we encourage people to use it.

The updated version will fully support Dzongkha computing on standard programs or applications like word processing, spreadsheets, presentations, web browsing and chatting.

Developed over a period of 13 months and at about US$ 80,000, the upgraded version has also dual booting system. It's a bilingual software, meaning that it supports both English and Dzongkha language, said Pema Geyleg.

DIT is aiming to develop software like text to speech, speech recognition system, and optical character recognition system on Dzongkha Debian Linux in the second phase. Text to speech program will read out text from the screen in Dzongkha. This will be of big use to people, who cannot read or write, he said. The Speech Recognition system will make the computer type any dictation. We have the capacity and are confident of doing it, said Pema Geyleg.

DIT has also released a 222-paged book on dzongkha computer terms. Officials said that they will also conduct a training for interested people. Meanwhile, the software will be posted on Druknet soon and will be downloaded for free also at the project site. Live CDs are available at DIT.

About Bhutan

The Kingdom of Bhutan is a landlocked South Asian nation situated between India and Tibet, People's Republic of China, and is often described as the last surviving traditional Himalayan Buddhist culture. The official language is Dzongkha, a language from the Sino-Tibetan family. Bhutan is very committed to preserve its local culture and traditions.

About Debian

Debian GNU/Linux is a free operating system, developed by more than a thousand volunteers from all over the world who collaborate via the Internet.

Debian's dedication to Free Software, its non-profit nature, and its open development model make it unique among GNU/Linux distributions.

The Debian project's key strengths are its volunteer base, its dedication to the Debian Social Contract, and its commitment to provide the best operating system possible.

Italian Debian Community Conference 2007, 15th 16th September, San Dona di Piave (VE, Italy)

contributed by andremachado, published on Fri Sep 14 13:18:51 2007 in event-announce

We are glad to announce the 3rd edition of the Italian Debian Community Conference (DCC-IT 2007).

This year the event is going to take place on 15th and 16th September in San Donà di Piave (Venice - Italy), once again as part of the End Summer Camp.

The conference is meant to give a common place for the Italian community to discuss ideas and share knowledge, where users, translators and developers can meet and directly interact. This is also going to be a good occasion for a GPG keysigning party.

There are already some talks (in Italian, of course) planned, but new speakers are always welcome.

Although this is mainly a nation-wide event, the italian Debian crowd would be happy to meet Debian people from abroad.

More information is available in English in a wiki. For any kind of questions, feel free to mail the italiandebconf mailing list

Listadmin: command line mailman moderator queue manipulation

published on Wed Sep 12 05:00:27 2007 in packages-news

Article submitted by Kaerast. We are running out of articles ! Please help DPOTD and submit good articles about software you like !

You’ve ended up moderating many Mailman lists across multiple servers, you’re losing track of what you’re moderating, the emails asking you to moderate posts are either filling up your inbox or getting ignored. Luckily there’s a command line tool which will make your life much easier.

Listadmin is a command line tool to manipulate the queues of messages held for moderator approval by mailman. It is designed to keep user interaction to a minimum, in theory you could run it from cron to prune the queue. It can use the score from a header added by SpamAssassin to filter, or it can match specific senders, subjects, or reasons.

It can handle multiple list servers, using multiple passwords, and in more recent versions can cope with SSL too. To get started you need to edit the .listadmin.ini file in your home directory. Mine looks something like this:

username kaerast@example.org
spamlevel 8
default skip

# example.org server
adminurl http://{domain}/cgi-bin/mailman/admindb/{list}
password "mypassword"
users@lists.example.org
process@lists.example.org
admin@lists.example.org

# example.com server
adminurl https://{domain}/mailman/admindb/{list}

password "myotherpassword"
supporters@lists.example.com

password "mythirdpassword"
staff@lists.example.com

This config files allows us to moderate queues on multiple lists using multiple passwords. With this configured, we can now run listadmin:

kaerast@bennet:~$ listadmin
fetching data for users@lists.example.org ... nothing in queue
fetching data for process@lists.example.org ... nothing in queue
fetching data for admin@lists.example.org ... nothing in queue
fetching data for supporters@lists.example.com ... nothing in queue
fetching data for staff@lists.example.com ...

[1/1] ============== staff@lists.example.com =======================
From:     kaerast@dodgit.com
Subject:  test
Reason:   Post by non-member to a members-only list            Spam? 0
Approve/Reject/Discard/Skip/view Body/Full/jump #/Undo/Help/Quit [S] ? r
Why do you reject? test messages aren't allowed
Submit changes? [yes]

Newer versions, ie. those in Lenny and Sid can also add and remove members from a list:

kaerast@hiro:~$ listadmin --add-member kaerast@example.com
process@lists.example.com
Ok

Listadmin is available in Ubuntu Feisty (universe) and all Debian versions. Only Debian Lenny and Sid have the add/remove subscribers functionality added.

duplicity: Encrypted bandwidth-efficient backup using the rsync algorithm

published on Sun Sep 9 05:00:27 2007 in packages-news

Entry submitted by Vincent Fourmond. DPOTD needs your help, please contribute!

I’ve recently grown paranoid about my data, and I keep using rsync to keep backup of various files a bit everywhere. It works great for most of the things I use, but it lacks fundamental things you would want from a real backup system, such as the possibility to come back to an earlier state.

So I went looking for something else, and I found that duplicity shows somehow the same syntax and ease of use than rsync: there is no need to write a configuration file, and it uses a very similar way to specify sources and targets. It features among others:

• incremental backup
• uses librsync to backup only what is necessary
• distant scp-like access
• no need to install duplicity on remote machine, just a scp server should do
• GPG encryption and signature to protect data saved on a not-so-trusted host

To use it, just run something like:

duplicity data scp://vincent@server/saves

Or, for local file backup:

duplicity data file:///var/backup/data

The target directory must exist: duplicity does not create it for you. If you don’t plan to use GPG encryption, be sure to add –no-encryption to the command-line. Here is duplicity in full action:

11:58 vincent@server ~ duplicity --no-encryption Data file:///home/vincent/saves
No signatures found, switching to full backup.
--------------[ Backup Statistics ]--------------
StartTime 1187949557.65 (Fri Aug 24 11:59:17 2007)
EndTime 1187949577.54 (Fri Aug 24 11:59:37 2007)
ElapsedTime 19.88 (19.88 seconds)
SourceFiles 3869
SourceFileSize 107865956 (103 MB)
NewFiles 3869
NewFileSize 107865956 (103 MB)
DeletedFiles 0
ChangedFiles 0
ChangedFileSize 0 (0 bytes)
ChangedDeltaSize 0 (0 bytes)
DeltaEntries 3869
RawDeltaSize 106836592 (102 MB)
TotalDestinationSizeChange 26514785 (25.3 MB)
Errors 0
-------------------------------------------------

duplicity was already part of Debian Sarge and Ubuntu Dapper. Development seems still alive, even though there are some bugs still at large.

Katapult : faster and easier access to your applications, bookmarks and files

published on Wed Sep 5 05:00:13 2007 in packages-news

Entry submitted by Ingo Wagener . DPOTD needs your help, please contribute!

Everybody must know the feeling – you installed this great program the other day and now you want to run it. You remember the name, but where in the world it is in the menu? Under System? Under Utilities or even Settings to name but a few options? And so the annoying search starts.

Granted, there are ways of getting round this such as the familiar ALT+F2 and then typing the entire name of the program. Some of us would go to (or already are on) the command line – again followed by typing the program name, perhaps aided by hitting a tab or two.

Those who are well organised – and at times I count myself amongst them – incorporate it into the quick starter on the taskbar so as to get accustomed to its icon and see how usage progresses.

But what do you do when you are not at your peak in terms of organisation (i.e. most of the time) or worse, you don’t even remember the full name of the program?

Help is at hand in the form of Katapult. This is a nifty little helper which, once installed, is called into action by hitting ALT+space and greets you with this:

Say I want to take a screenshot. Running KDE I want to call up the program ksnapshot. What is the quickest way of getting to it? 5 keystrokes as far as I am concerned – this is without having a special keyboard shortcut set up, which obviously could reduce this number. How? Here goes, ALT+space and you get the above, then I type a K, as the program I am after starts with a K followed by an S and finally the N and I get the following:

All I have to do is hit enter and my desired programme comes up. So how exactly does it work? Why do I have to type KSN to get the shortcut for Ksnapshot? Here is a breakdown of what happens in between after I have typed both the K and the KS:

You can see the typed letters highlighted in blue and cycles through all the possibilities until it hits on the one you want – and you press enter.

But Katapult will not only work on programs but also functions as a calculator, it even indexes files! Thus, if I wanted to quickly find out what the result of 56324/18*17 is I’d type ALT+space followed by the what I want to calculate. Katapult will answer to this query as follows:

Alternatively, if I wanted to listen to a specific song like “The battle of Epping Forest” I’d type any part of the song’s name, in this case “epping” and Katapult greets me with the following result:

But that is not all, it also indexes your bookmarks. To give you an idea of its manifold capabilities here is a screenshot of its configuration window:

All I can say is that is has increased my productivity, and prolonged the life of my mouse’s batteries in equal measure.

Conky: highly configurable system monitor for X

published on Sun Sep 2 05:00:23 2007 in packages-news

Entry submitted by Casey Stamper. DPOTD needs your help, please contribute!

Conky is one of my favorite applications for all of my Linux distros. It is a light-weight system monitor (according to the project page) that can monitor many different aspects of your computer. You choose what to monitor and you choose where the monitor is displayed on your desktop through use of a configuration file - .conkyrc. I like to have my display on the top right of the screen and I have the background transparent so it looks like it floats on the desktop.

Here is a screenshot: (click on the image for full size)

I especially like the CPU temperature monitor because I like to keep track of how hot the CPU gets when I’m doing CPU-intensive operation. The application is very light on resources (especially important for my Inspiron 5160) but allows you to keep track of a lot of system parameters without the bloat of a GUI front end.

Among other things, I monitor disk space, memory usage, system load, network download and upload speed, internet connections by protocol, RAM usage, swap usage and running processes. Although it takes up a bit more memory to do so, I also monitor the /var/log/messages file (the same as having a window open running tail -f /var/log/messages just to see if anything is happening behind the scenes that I should be aware of.

With this utility running all the time, if something should suddenly crash or if I have any slowdowns or anything else unusual, a quick glance at these various readouts will usually allow me to narrow the problem down to something specific.

If you use GKrellM or another built-in monitoring package, try this one out - I think you will like it.

Links

• Conky’s website
• Table of variables
• This is my .conkyrc
• The man page.
• Many screenshots and examples of how to use this great little app

Bdale Garbee interview: Debian stays true to its roots

contributed by andremachado, published on Sat Sep 1 14:41:36 2007 in news

Bdale Garbee, former Debian Project Leader, now chief technologist at HP Open Source & Linux Organization, talked about Debian Project.

He highlighted the history, his and other developers motivations and some of the key advantageous characteristics of Debian Project, like its Constitution, Social Contract, elected Debian Project Leader, Secretary, Technical Commitee, and Debian Policy for developers.

Since Debian isn't a company, developers don't have to worry about being bought or sold, going through a hostile take-over, answering to shareholders or going bankrupt, Garbe said. A motivated developer with an aligned profile to the project culture could become a New Maintainer.

Other people beyond coders and developers can help, for example, translating, creating art, giving legal advice, accounting, maintaining infrastructure, documentation and much more.

Debian runs on more kinds of computer hardware than any other Linux distribution, and includes more packaged and tested software than any other distribution I know of. It's used in everything from wrist watches to mainframes, including desktops, notebooks, handheld devices and mobile phones. Without the constraints of a financial enterprise, people are free to work on the things that really matter to them. The Debian Project is a collaborative community that enables tremendous innovation and endless possibilities, which is why you may hear Debian referred to as the universal operating system. Debian continues to thrive after 14 years.

As I roll the clock forward, I realize that derivatives will come and go, but -- unless the Debian Project loses its way in the next five to 10 years -- it will still be around, still be an industry enigma. There will always be people who don't understand how it works or why we volunteers do what we do, but Debian will continue to fuel technical innovation and evolve its social processes. People will still have fun working together and making an extraordinarily significant contribution to computer users around the world, Garbe said.

burgerspace: a free clone of the classic arcade game Burgertime

published on Wed Aug 29 06:00:19 2007 in packages-news

Entry submitted by Alexey Beshenov. DPOTD needs your help, please contribute!

Burgertime (originally entitled バーガータイム, Hamburger) is a popular 1982 Japanese arcade game created by Data East Corporation. The game even has an interesting entry in Wikipedia. Among other ports and remakes, there are a free X11 clone called “BurgerSpace” written in C++ by Pierre Sarrazin.

The behavior of the original arcade was not replicated exactly in BurgerSpace, but clone has the same scenario. You play the part of a chef Peter Pepper who must create burgers by stepping repeatedly on the ingredients until they fall down onto trays. It’s not so easy since you also must avoid food characters who chase you around the maze.

Evil food enemies (namely Mr. Hot Dog, Mr. Pickle and Mr. Egg) could be temporarily killed by crushing them under falling burger slices or dropped with them. The dropped enemies are stunned for a few seconds. You can also shake pepper on nearby monsters to make them harmless for a few seconds.

The game could be started via the command burgerspace or from the entry in the GNOME Games menu.

Use the following keys:

↑ ↓ ← →

Move.

Ctrl

Throw pepper.

P

Pause / resume game.

Esc

Quit the game.

(Unfortunately, there are no complete keystroke configuration.)

You can rich extra scores / peppers by collecting appearing things. Level will be completed if you create all burgers and the next level will be based on more complex maze layout, increased number of burger pieces and elevated speed. Game records available from the official webpage and you can report your outstanding scores to maintainer.

Yo

Program requires the SDL multimedia library. Burgerspace could be used on GNU/Linux machines and there are even a port for some-proprietary-system. The burgerspace package is available in both Debian and Ubuntu. Have fun!

DebConf Resources

published on Tue Aug 28 21:38:00 2007 in debconf-news

I just setup a DNS entry for panama.mini.debconf.org, on request of David Moreno Garza. He also got a mailing-list for that upcoming mini Debian Conference.

Which reminded me to blog about debconf.org resources again, so that more people know/remember that there is something they can use whenever they organize a Debian meeting.

If you happen to organize a meeting of Debian Developers / interested Debian people you can chose to use any debconf.org resource you need for it. This currently means:

Want more? We have a page listing most of our resources, maybe you find something you need.

Want something? Mail admins@debconf.org and describe what you want, most possibly we will make it happen. Or try to get one of us admins on IRC, you are looking for one of the nicks Ganneff, mhy, sgran, gwolf or h01ger. No, we do not bite … usually. :)

IPTraf, a ncurses based LAN monitor

published on Sun Aug 26 05:00:42 2007 in packages-news

Entry submitted by Bart Veraart. DPOTD needs your help, please contribute!

Sometimes you just want to see what connections your machine is making to the outside world and what ports it’s using. While wireshark and tcpdump are really nice for inspecting detailed package contents. IPTraf is really about connections and interface statistics. Because iptraf is based on ncurses the program can be run from a text-console and still have a (primitive) `gui`. Navigation through the menus can be done using your arrow keys. Most of the time all the available options and their keys are shown on the bottomline of the sreen.

Starting up

By default the program is not accessible by ‘normal’ users so you’ll need root access. Also iptraf can put your interfaces in promiscuous mode (this will probably show up in your logfiles as: ‘device eth0 entered promiscuous mode’). Promiscuous mode can be turned off and on in the configuration menu. If no options are given through the commandline iptraf starts up with a splashscreen and then a menu. Some of the menuitems can be reached directly from the commandline (try using ‘iptraf -i all’ if you want to startup in IP traffic monitoring mode).

Configuration

There are some configuration options you might want to check. Turning on reverse DNS Lookups and service names comes in handy when using the IP traffic monitor. Iptraf comes with a separate reverse lookup server -rvnamed- wich is only started and used by iptraf to keep it from hanging on slow lookups. If there’s a lot of network traffic on your box try applying some filters.

Filtering

Filters can be useful if you only want to see info about traffic on certain connections, ports and/or protocols. Filters can be saved, deleted and edited. Multiple rules can be defined.

Screenshots

(Click on the image to enlarge)

Connections	Configuration	Filters	Interface statistics

More information

• IPTraf website
• IPTraf manual
• HOWTO: Monitoring network traffic with iptraf and rrdtool

IPTraf has been available since ages ago in both Debian and Ubuntu.

ipcalc: network calculator on the command line

published on Wed Aug 22 05:00:07 2007 in packages-news

Article submitted by Javier Barroso. We are running out of articles ! Please help DPOTD and submit good articles about software you like NOW !

Ipcalc is a command-line tool which allows the user to get useful data from a ip and a netmask.

Ipcalc returns the network address, netmask, network address in CIDR notation, min/max IP addresses, broadcast address and the number of hosts of network.

Ipcalc usage is:

Usage: ipcalc [options] <ADDRESS>[[/]<NETMASK>] [NETMASK]

A example could be:

$ ipcalc 10.0.0.28 255.255.255.0
Address:   10.0.0.28            00001010.00000000.00000000. 00011100
Netmask:   255.255.255.0 = 24   11111111.11111111.11111111. 00000000
Wildcard:  0.0.0.255            00000000.00000000.00000000. 11111111
=>
Network:   10.0.0.0/24          00001010.00000000.00000000. 00000000
HostMin:   10.0.0.1             00001010.00000000.00000000. 00000001
HostMax:   10.0.0.254           00001010.00000000.00000000. 11111110
Broadcast: 10.0.0.255           00001010.00000000.00000000. 11111111
Hosts/Net: 254                   Class A, Private Internet

Ipcalc has been available in Debian at least since v3.1 (’Sarge’) and in Ubuntu since Warty. apt-get install ipcalc will install it for you.

jed - Pocket sized emacs

published on Sun Aug 19 05:00:05 2007 in packages-news

Article submitted by François-Denis Gonthier. We have run out of good articles! Please help DPOTD and submit good articles about software you like!

I’m a big fan of GNU Emacs, it’s a very powerful and ultra customisable editor. I have it setup just the way I want, with tons of packages. That means that although my Emacs setup suits me fine for long coding sessions, it takes several seconds to start, even on a moderately fast computer.

When you work in a console, and all you want is to edit some files, and edit them now, you gotta have something that starts in a snap. Jed is the editor I use for that.

Jed showing a bit of Emacs code.

The obvious advantages of Jed are that it starts much faster than Emacs, but still provides the basic key-mappings and features of the default Emacs setup. Out of the box, it supports syntax colouring for several programming languages: C/C++, S-Lang, FORTRAN, LaTeX, Java, Python, Perl, Bash and more. Since it’s an extensible editor, several add-ons (modes) have been written and are available in the Jed Modes Repository.

For people that are interested in having a full-featured editor, but aren’t crazy about the Emacs key bindings, Jed has a nice console menu interface. Menus can be activated with the F10 key, and then browsed with the arrows key, just like the ol’ DOS editors. Most menu items also have shortcuts, for quicker access the next use. For the less expert users, like myself, menus are very useful; but avoiding the F10 key at the corner of the keyboard is a time saver, as tiny as it may sound.

The Jed menus come with some nice touches that Emacs has acquired just recently. In the “Windows” menu, you can see that Jed offers 9 different colour themes for the terminal, a nice touch for people allergic to white-on-black text, or with difficult display devices.

I personally use Jed as a light editor, but Jed is a very customisable platform. It is linked with the S-Lang library, which can be used to heavily customise the editor. I know little of the S-Lang language, just what I need to set a few shortcuts, but the S-Lang functions provided by Jed are well documented on its home page: http://www.jedsoft.org/jed/doc/jedfuns.html

It is also interesting to know that Jed has a native X11 interface, which is installed by the xjed package. Jed is not as well adapted to X11 than Emacs is, but XJed does bring some interesting improvements like mouse support, and of course key bindings which are not limited by any terminal protocol. Personally, I think that the XJed default configuration should be edited a bit (I use Ubuntu, but tend to suppose it’s not very different in Debian). When XJed starts on my computer, it looks like Jed was started in XTerm, with extremely tiny fonts, and an ugly font. I am sure XJed can be conveniently and easily configured but giving you a bad first impression of Jed is not something I want. I suggest you to try running the console version of Jed in your favourite terminal emulator, then play with it a bit.

The final proof that Jed is a mature and fully-featured editor is that it obeys Zawinski’s Law (Zawinski’s Law), which state that “a program attempts to expand until it can read mail”. Jed has a mail reader called rmail, it can be invoked by hitting M-x (Alt+x) then typing rmail.

Jed has been available in Debian and Ubuntu for ages.

Quick start shortcuts

Here is a few shortcuts you may find useful while playing with Jed for the first time. As usual, C = Ctrl, M = Meta (usually Alt).

C-h

Invoke the help system

C-x C-c

Quit jed

C-x C-f

Open a file

C-x C-k

Close a file

C-x 2

Split a window

C-x o

Move to the next window

C-SPACE

Set the beginning of selection (C-SPACE cancels selection region)

C-Shift-w

Cut

M-Shift-w

Copy

C-y

Paste

C-a

Go to the beginning of line

C-e

Go to the end of line