• a podcasting client
• an app to record GPS files while running
• an app for turn-by-turn navigation

The podcasting client was easy, I’ve already used instacast on my iPad, it syncs with iCloud and works perfectly for what I need.
This post deals with the second app, the running app. When I was on Android, I usually used runkeeper. It worked fine and the only downside was that I had to go to the website to get the GPX file (and they tried to hide it pretty well). On iOS, the app seemed a bit… jumpy when it comes to filtering the GPS signal:

This wasn’t really what I was looking for.
I also tried a few other ones, but most of them where targeted towards getting you on some website and wanting you to buy some sort of premium subscription.
I looked for a paid app that isn’t free but offers good value, this is where I noticed Runmeter:

The company that develops it has a nice comparison online. While this has to be taken with a grain of salt, I think they did an ok job.
Things I like:

• It has support for adding runs to the calendar after you’re done. It’s kinda neat to see your calendar and know what you’ve done next to all the other stuff.
• It is able to attach a gpx to an email and export it that way. It is also able to send customized reports with direct links. I’ll probably use this to automate the import into my custom tailored runalog (that is in dire need of a bit of code polish):
  
• It is able to customize the voice feedback. You can pretty much combine whatever information you want to hear.
• It doesn’t force me to go to any website. The only thing you have to sign up for is sending automated emails after every run. You can also use the iPhone to send those, but iOS limits apps to just popping up a prefilled “compose” window and not actually sending them. I don’t have a problem with using the developers webservice.
• It has a whole lot of social yadda yadda integrated. I don’t use it, but I like the fact that I could.

So far I am happy with the app, it’s actively being developed and the price of 4.99$ is ok for something that I use every day.
–> App store link

PDF available here.

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> ruby test.rb --runner=xml
.rvm/gems/ruby-1.8.7-p334/gems/test-unit-2.3.2/lib/test/unit/testresult.rb:28: uninitialized constant Test::Unit::TestResult::TestResultFailureSupport (NameError)

To solve this, you have to make sure that the file actually loads the test-unit 2.x GEM as opposed to using the included 1.x version from stdlib. You can do this by simply adding this line to your ruby file:

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gem "test-unit"

• move the blog to Amazon S3
• thin out the softwarestack on my VPS a bit
• change the blog template to something custom

Fun times ahead :)

I always used the alias (blog.marc-seeger.de/year/month/day/slug) as an identifier on disqus. The durpal module, by default, uses the drupal node ID (blog.marc-seeger.de/node/123) as the identifier.
It’s easy enough to make some small changes though. All of this is in the disqus.module file. Here is the original passage that sets the disqus URL:

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        // Build the absolute URL without the alias for the disqus_url flag.
        $node->disqus['url'] = url("node/$node->nid", array(
          'alias' => TRUE,
          'absolute' => TRUE, 
        ));

Just change the ‘alias’ parameter to false to get your aliased path as the disqus URL:

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          'alias' => FALSE,

This tells the url() function to NOT assume that the alias is already resolved.
The API for the url function describes it as “Whether the given path is a URL alias already.” The second thing you have to change is the disqus identifier. Also in the disqus.module search for this:

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    // Provide the identifier.
        $node->disqus['identifier'] = 'node/' . $node->nid;

and replace it by:

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        // Provide the identifier.  
        $node->disqus['identifier'] = url("node/$node->nid", array(
          'alias' => FALSE,
          'absolute' => TRUE,
        ));

Worked for me :)

iPlayer:

Hulu:

These services usually use your IP address to determine what country you’re from. An obvious solution would be to just run the whole traffic over an HTTP proxy that is standing inside of the country in question. The problem is that while browsers tend to honor HTTP proxy settings, the flash player will try a direct socket connection first. This could be circumvented by blocking ports, but that is one of the more annoying solutions to the problem.

Something interesting can be seen by looking at how the iPlayer does the geo locating. It will check the IP and, if successful, pass out the URL for the actual streaming video. This URL can be accessed from anywhere, the only problem is to somehow get at it.

While VPN solutions work, they usually will tunnel ALL of your traffic over the comparatively slow VPN connection, will require manual enabling/disabling, won’t work with e.g. the apple tv out of the box and are in general a pain to set up. If you want to go this way, I recommend a look over to lowendbox.com for matching VPS systems or at one of the many commercial VPN providers which are usually more expensive than setting it up yourself.

I recently came across a pretty interesting service that has a different approach to this problem. The service is Unblock US and they provide a DNS based solution to the whole ‘geolocation-check’ topic. After you signed up (free 1 week trail without payment details) you’ll have to use their servers as DNS servers.

What they will do is redirect all DNS requests to geo-location checks to their own IPs where e.g. a squid server will forward the connection with an IP address that matches the country in question (e.g. the US for Hulu and the UK for iPlayer). The advantages of this approach are:

• Only the necessary traffic will run over the slow proxy. Most of the time, the real video will come directly to you via your regular internet connection

• You can just put the DNS servers into your router and all of your devices (iPad, AppleTV, Laptops, … ) will be able to automagically use the geo-restricted services

• While the service provider might redirect any website to their servers, they still can’t fake an SSL certificate, so anything important should still be safe (you hopefully ARE using SSL/TLS!)

• In contrast to a VPN solution, this allows you to access services from more than just one country (e.g. Netflix from the US, iPlayer from the UK, TruTV from Germany, TF1 from France)

The price for the service isn’t too bad either. When prepaying for a year, it will come down a little bit less than 3 Euro/month. Monthly payments will be approximately 3.50 Euro/month.

A downside of this approach is, that they have to ‘whitelist’ services and figure out which URLs/Domains are responsible for the GeoIP checks. With a VPN, you can use ANY service within that country without further actions.

While I haven’t signed up with them so far, I’m seriously considering it once I have some free time on my hands to actually watch all the tv and movies.

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class Derp
  @@numero_uno = "Something about cake"
  @@numero_dos = "Number one was a lie"
  #this creates the methods when the class is loaded  
   self.class_variables.each{ |sym| class_eval("def self.#{sym.gsub('@@','')}; return #{sym}; end;") }
end

puts Derp.numero_uno
puts Derp.numero_dos

This is a bit of magic and even has an eval(), but it works…

It took a while but here is a new mix on 8tracks.
Have fun :)

Initially, I wanted to use it as a no-hassle solution for OSX Time Machine backups. This worked perfectly and I can easily push 5-6 MB/s over Wifi to the drive. After being happy with this, I decided to see if there is anything else interesting going on with the drive.

Here are some findings: - The MyBook Live admin console is done in PHP using the full blown cakePHP framework:

- The MyBook Live has a hidden page to enable SSH at “/UI/ssh”:

- It has an 800MHz CPU with 256 MB RAM:

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# cat /proc/cpuinfo  
processor : 0  
cpu       : APM82181  
clock     : 800.000008MHz  
revision  : 28.129 (pvr 12c4 1c81)  
bogomips  : 1600.00  
timebase  : 800000008  
platform  : PowerPC 44x Platform  
model     : amcc,apollo3g  
Memory        : 256 MB

• The internal harddrive is using ext4:

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# cat /etc/mtab  
/dev/md1 / ext3 rw,noatime 0 0
tmpfs /lib/init/rw tmpfs rw,nosuid,mode=0755,size=50M 0 0
proc /proc proc rw,noexec,nosuid,nodev 0 0
sysfs /sys sysfs rw,noexec,nosuid,nodev 0 0
procbususb /proc/bus/usb usbfs rw 0 0
udev /dev tmpfs rw,mode=0755 0 0
tmpfs /dev/shm tmpfs rw,nosuid,nodev,size=50M 0 0
devpts /dev/pts devpts rw,noexec,nosuid,gid=5,mode=620 0 0
tmpfs /tmp tmpfs rw,size=50M 0 0
/var/log /var/log.hdd none rw,bind 0 0
ramlog-tmpfs /var/log tmpfs rw,size=20M 0 0
/dev/sda4 /DataVolume ext4 rw,noatime,nodelalloc 0 0
/DataVolume/cache /CacheVolume none rw,bind 0 0
/DataVolume/shares /shares none rw,bind 0 0
/DataVolume/shares /nfs none rw,bind 0 0
none /sys/kernel/security securityfs rw 0 0
rpc_pipefs /var/lib/nfs/rpc_pipefs rpc_pipefs rw 0 0
nfsd /proc/fs/nfsd nfsd rw 0 0

• It is using lots of open source software:

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# ls -l /etc/init.d/
total 456
-rw-r--r-- 1 root root  1510 Mar  4  2010 README  
-rwxr-xr-x 1 root root  6532 Sep 20 22:34 apache2  
-rwxr-xr-x 1 root root 18698 Mar  4  2010 autofs  
-rwxr-xr-x 1 root root  2359 Jul 31  2010 avahi-daemon  
-rwxr-xr-x 1 root root  2155 Mar  4  2010 bootlogd  
-rwxr-xr-x 1 root root  1988 Mar  4  2010 bootmisc.sh  
-rwxr-xr-x 1 root root  3004 Mar  4  2010 checkfs.sh  
-rwxr-xr-x 1 root root  9831 Mar  4  2010 checkroot.sh  
-rwxr-xr-x 1 root root  2602 Jun 16  2010 cron  
-rwxr-xr-x 1 root root  4636 Mar  4  2010 dbus  
-rwxr-xr-x 1 root root   833 Jul 14  2010 emi-patch-check.sh  
-rwxr-xr-x 1 root root  6593 Mar  4  2010 exim4  
-rwxr-xr-x 1 root root   959 Jun 18  2010 factoryRestoreSettings.sh  
-rwxr-xr-x 1 root root  1397 Sep 13  2010 halt  
-rwxr-xr-x 1 root root 10725 Mar  4  2010 hdparm  
-rwxr-xr-x 1 root root  1287 Mar  4  2010 hostname.sh  
-rwxr-xr-x 1 root root  5061 Jul  9  2010 hwclock.sh  
-rwxr-xr-x 1 root root  5079 Jul  9  2010 hwclockfirst.sh  
-rwxr-xr-x 1 root root  3117 May 14  2010 ifplugd  
-rwxr-xr-x 1 root root  2518 Mar  4  2010 ifupdown  
-rwxr-xr-x 1 root root  1046 Mar  4  2010 ifupdown-clean  
-rwxr-xr-x 1 root root  2814 Aug  2  2010 itunes  
-rwxr-xr-x 1 root root  1484 Mar  4  2010 killprocs  
-rwxr-xr-x 1 root root   851 Mar 15  2010 lltd  
-rwxr-xr-x 1 root root  1051 Mar  4  2010 lvm2  
-rwxr-xr-x 1 root root  1845 Jul 31  2010 mDNSResponder  
-rwxr-xr-x 1 root root  1916 Mar  4  2010 mdadm  
-rwxr-xr-x 1 root root  6226 Mar  4  2010 mdadm-raid  
-rwxr-xr-x 1 root root  1726 Jan 14 18:25 mionet  
-rwxr-xr-x 1 root root  1793 Mar  4  2010 module-init-tools  
-rwxr-xr-x 1 root root  1546 Jul  9  2010 monitorio  
-rwxr-xr-x 1 root root  2625 Sep 20 22:34 mountDataVolume.sh  
-rwxr-xr-x 1 root root   620 Mar  4  2010 mountall-bootclean.sh  
-rwxr-xr-x 1 root root  1956 Mar  4  2010 mountall.sh  
-rwxr-xr-x 1 root root  2194 Mar  4  2010 mountdevsubfs.sh  
-rwxr-xr-x 1 root root  2476 Mar  4  2010 mountkernfs.sh  
-rwxr-xr-x 1 root root   618 Mar  4  2010 mountnfs-bootclean.sh  
-rwxr-xr-x 1 root root  2330 Mar  4  2010 mountnfs.sh  
-rwxr-xr-x 1 root root  1321 Mar  4  2010 mountoverflowtmp  
-rwxr-xr-x 1 root root  3668 Mar  4  2010 mtab.sh  
-rwxr-xr-x 1 root root  5755 Mar  4  2010 mysql  
-rwxr-xr-x 1 root root  2515 Mar  4  2010 mysql-ndb  
-rwxr-xr-x 1 root root  1905 Mar  4  2010 mysql-ndb-mgm  
-rwxr-xr-x 1 root root  3180 Aug 11  2010 netatalk  
-rwxr-xr-x 1 root root  1844 Mar  4  2010 networking  
-rwxr-xr-x 1 root root  5964 Mar  4  2010 nfs-common  
-rwxr-xr-x 1 root root  4563 Mar 19  2010 nfs-kernel-server  
-rwxr-xr-x 1 root root  1308 Aug  2  2010 ntpdate  
-rwxr-xr-x 1 root root  2066 Mar  4  2010 portmap  
-rwxr-xr-x 1 root root  1247 Mar  4  2010 procps  
-rwxr-xr-x 1 root root 29492 May 27  2010 ramlog  
-rwxr-xr-x 1 root root 10036 Mar  4  2010 rc  
-rwxr-xr-x 1 root root   788 Mar  4  2010 rc.local  
-rwxr-xr-x 1 root root   117 Mar  4  2010 rcS  
-rwxr-xr-x 1 root root   639 Mar  4  2010 reboot  
-rwxr-xr-x 1 root root  1710 Jun 11  2010 reset_button_mon  
-rwxr-xr-x 1 root root   941 Mar  4  2010 rmnologin  
-rwxr-xr-x 1 root root  5108 Mar  4  2010 rsync  
-rwxr-xr-x 1 root root  2850 Mar  4  2010 rsyslog  
-rwxr-xr-x 1 root root  2533 Oct 15 02:25 samba  
-rwxr-xr-x 1 root root   765 May 11  2010 saveclock.sh  
-rwxr-xr-x 1 root root   918 May  2  2009 screen-cleanup  
-rwxr-xr-x 1 root root  2283 Mar  4  2010 sendsigs  
-rwxr-xr-x 1 root root   590 Mar  4  2010 single  
-rw-r--r-- 1 root root  4167 Mar  4  2010 skeleton  
-rwxr-xr-x 1 root root  3364 Mar  4  2010 smartmontools  
-rwxr-xr-x 1 root root  3845 Aug  2  2010 ssh  
-rwxr-xr-x 1 root root   525 Mar  4  2010 stop-bootlogd  
-rwxr-xr-x 1 root root  1096 Mar  4  2010 stop-bootlogd-single  
-rwxr-xr-x 1 root root   551 Mar 18  2010 sudo  
-rwxr-xr-x 1 root root  4176 Jan 14 22:57 twonky  
-rwxr-xr-x 1 root root  7473 May 13  2010 udev  
-rwxr-xr-x 1 root root  1001 May 13  2010 udev-mtab  
-rwxr-xr-x 1 root root  3175 Mar  4  2010 umountfs  
-rwxr-xr-x 1 root root  2140 Mar  4  2010 umountnfs.sh  
-rwxr-xr-x 1 root root  1456 Mar  4  2010 umountroot  
-rwxr-xr-x 1 root root  2006 May 27  2010 upnp_nas  
-rwxr-xr-x 1 root root  1815 Mar  4  2010 urandom  
-rwxr-xr-x 1 root root   903 May 28  2010 vftd  
-rwxr-xr-x 1 root root  2516 Aug  2  2010 vsftpd  
-rwxr-xr-x 1 root root  1777 Mar  4  2010 x11-common  
-rwxr-xr-x 1 root root  1923 Mar  4  2010 xmail

• A somewhat recent SVN kernel:

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# uname -a  
Linux MyBookLive 2.6.32.11-svn21605 #1 Fri Oct 15 17:13:23 PDT 2010 ppc GNU/Linux

• Debian Lenny (I might have added contrib and non-free to this):

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# cat /etc/apt/sources.list | grep lenny  
deb http://ftp.us.debian.org/debian/ lenny main contrib non-free  
deb-src http://ftp.us.debian.org/debian/ lenny main contrib non-free  
deb http://mirrors.usc.edu/pub/linux/distributions/debian/ lenny main contrib non-free  
deb-src http://mirrors.usc.edu/pub/linux/distributions/debian/ lenny main  
deb http://security.debian.org lenny/updates main contrib non-free  
deb-src http://security.debian.org/ lenny/updates main contrib non-free

• They even deliver a Java VM with their weird mionet service:

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# /usr/mionet/bin/cvm -version  
Product: Sun Java Media Client 1.3-b111 WesternDigital-b003 (built on 10/Jun/2010 00:33 IST)  
Profile: Foundation Profile (Security Optional Package) 1.1.2 (Specification 1.1.2)  
JVM:     1.1.2 1.3-b111 WesternDigital-b003 (mixed mode)

Since we’re pretty good on available RAM, there is a bunch of fun stuff we can do (cough)

1. apt-get install pptpd
2. open /etc/pptpd.conf and enter the following

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localip 192.168.10.1  
remoteip 192.168.10.101-200

1. echo 1 > /proc/sys/net/ipv4/ip_forward
2. edit /etc/ppp/chap-secrets and add a user (username [tab] pptpd [tab] password [tab] *)
3. set up the iptables rules and replace OUTBOUND_IP_ADDRESS with your server’s IP

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iptables -A INPUT -p tcp --dport 1723 -j ACCEPT  
iptables -A INPUT -p 47 -j ACCEPT  
iptables -A FORWARD -i ppp+ -o venet0 -j ACCEPT  
iptables -t nat -A POSTROUTING -s 192.168.10.0/24 -j SNAT --to-source OUTBOUND_IP_ADDRESS

1. edit /etc/ppp/pptpd-options and enter these options:

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name pptpd  
refuse-pap  
refuse-chap  
refuse-mschap  
require-mschap-v2  
require-mppe-128  
proxyarp  
lock  
nobsdcomp  
novj  
novjccomp  
nologfd  
ms-dns 8.8.8.8  
ms-dns 8.8.4.4

If you want to make these permanent, edit /etc/sysctl.conf and make sure that “net.ipv4.ip_forward=1” doesn’t have a hash (#) in front of it.
After this, copy the iptables rules from above to /etc/rc.local so they are executed on boot.
This should give you an IP from the US that you can connect to with your tech gadgets :)

You can get the electostatic replacement pads on Amazon Germany (13.99 Euros for 20 pads) and on Amazon US for 7 USD for 20. On Amazon.com, there is also an offer with 24 for 7.50 USD, but I’m not quite sure if they fit 100% (robomaid <-> robomop).

1. Open “Disc Utility” and click the new image icon:
   
2. Create a sparse bundle and be sure to enable encryption:
   
3. Enter a password for it:
   
4. After this, your image should be created and mounted. Go to the terminal and find out its disk device:
   

       $ mount  
       [...]  
       /dev/disk1s2 on /Volumes/My personal stuff (hfs, local, nodev, nosuid, journaled, noowners, mounted by mseeger)  
   

   After you found out the device, check the image’s UUID:

       $ diskutil info /dev/disk1s2 | grep UUID  
       Volume UUID:              8F37F1F3-71EB-35AA-BED9-237DCD2A0842  
   

   There we go, our image’s UUID is 8F37F1F3-71EB-35AA-BED9-237DCD2A0842
5. Create a folder you want to mount it to later
6. Open the system’s fstab files by typing “sudo vifs” into the terminal
7. Insert the following line, replace UUID and path with your values:

       UUID=8F37F1F3-71EB-35AA-BED9-237DCD2A0842 /Users/mseeger/stuff hfs rw 1 0
   

   p.s. vifs will put you in VI, so just press ‘i’ to get into insertion mode and [escape], :wq, [enter] to save the file
8. Drag the sparse image into your user’s “login items” (System Preferences) and it will be automatically mounted on boot. Since the image’s key will be placed into the keychain that you unlock when you login, the image will be ready to use at the designated folder :)

That’s it, have fun :)

The first thing to do will be inserting the javascript part of the integration into our /views/layout.erb file. This file contains (among other things) the header that is part of every page. This code doesn’t need any customization and can just be copied into the head section of the HTML

<script type="text/javascript">
/* <![CDATA[ */
    (function() {
        var s = document.createElement('script'), t = document.getElementsByTagName('script')[0];

        s.type = 'text/javascript';
        s.async = true;
        s.src = 'http://api.flattr.com/js/0.6/load.js?mode=auto';

        t.parentNode.insertBefore(s, t);
    })();
/* ]]> */
</script>

The HTML part of the API has to be added to the “/views/_article.erb” template that is responsible for diaplaying the actual content of each blogpost.
In this case, just replace the “data-flattr-uid” value with your fattr username.

<a class="FlattrButton" style="display:none;" title="<%= article.title %>" data-flattr-uid="rb2k" data-flattr-category="text" href="<%= Serious.url + article.url %>"><%= article.title %></a>

This should be it, happy flattr’ing

p.s. acquia is hiring ;)

  before do
    headers['Cache-Control'] = "public, max-age=#{Serious.cache_timeout}"
  end

Since I like to keep my application logic out of the webserver, I decided to use Ryan Tomayko’s rack-cache middleware.
While using the nginx-internal caching feature might be the faster solution, I like the feeling that I can actually read the sourcecode easily if I ever happen to encounter bugs.

When looking at the headers of my blog, you can now see a new attribute called “X-Rack-Cache”.
When hitting a page that wasn’t in the cache, it looks like this:

Age: 0  
X-Rack-Cache: miss, store

and if you happen to hit something cached, you’ll see this:

Age: 217  
X-Rack-Cache: fresh  

The “Age” header will tell you how many seconds ago the HTML had been generated. I currently set the maximum cache vaildity time to 300 seconds. If you happen to hit something in the cache that is OLDER than 300 seconds, you should see this:

Age: 0  
X-Rack-Cache: stale, invalid, store

Trying to see if the added caching actually made a difference was pretty satisfying:

Before

$ ab -kc 10 -t 30 http://blog.marc-seeger.de/
Server Software:        nginx/0.8.52
Concurrency Level:      10
Time taken for tests:   30.058 seconds
Complete requests:      420
Failed requests:        0
Write errors:           0
Keep-Alive requests:    420
Requests per second:    13.97 [#/sec] (mean)
Time per request:       715.662 [ms] (mean)
Time per request:       71.566 [ms] (mean, across all concurrent requests)
Transfer rate:          150.36 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   2.4      0      16
Processing:    89  704 873.3    530    9556
Waiting:       72  654 870.6    498    9539
Total:         89  705 873.5    530    9556

Percentage of the requests served within a certain time (ms)
  50%    530
  66%    572
  75%    613
  80%    671
  90%   1055
  95%   1448
  98%   2804
  99%   5267
 100%   9556 (longest request)

After

$ ab -kc 10 -t 30 http://blog.marc-seeger.de/

Server Software:        nginx/0.8.52
Concurrency Level:      10
Time taken for tests:   30.007 seconds
Complete requests:      7165
Failed requests:        0
Write errors:           0
Keep-Alive requests:    7099
Requests per second:    238.78 [#/sec] (mean)
Time per request:       41.880 [ms] (mean)
Time per request:       4.188 [ms] (mean, across all concurrent requests)
Transfer rate:          2203.54 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   1.6      0      18
Processing:    18   42  69.4     34    2433
Waiting:       17   39  64.9     32    2401
Total:         18   42  69.8     34    2433

Percentage of the requests served within a certain time (ms)
  50%     34
  66%     37
  75%     40
  80%     43
  90%     61
  95%     74
  98%     86
  99%    121
 100%   2433 (longest request)

Not too shabby :)

p.s. when configuring rack-cache, the “allow_reload” option should be set to false unless you want to allow everybody to forcefully ignore your cache.

Here is the code, a simple sieve of eratosthenes:

def prime_sieve_upto(n)
  all_nums = (0..n).to_a
  all_nums[0] = all_nums[1] = nil
  all_nums.each do |p|
    #jump over nils
    next unless p
    #stop if we're too high already
    break if p * p > n
    #kill all multiples of this number
    (p*p).step(n, p){ |m| all_nums[m] = nil }
  end
  #remove unwanted nils
  all_nums.compact
end

starting = Time.now
amount = 2500000
primes = prime_sieve_upto(amount)
puts "Found #{primes.size} in the numbers from 0 to #{amount} in #{Time.now - starting}s"

On my Macbook Pro (2.6 GHz Core2Duo), the different VMs perform as follows:

ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.4.0]:
$ ruby prime_fast.rb
Found 183072 in the numbers from 0 to 2500000 in 3.543216s

rubinius 1.1.1 (1.8.7 release 2010-11-16 JI) [x86_64-apple-darwin10.4.0]
$ rbx prime_fast.rb
Found 183072 in the numbers from 0 to 2500000 in 1.333367s

UPDATE:
rubinius 1.2.0 (1.8.7 release 2010-12-21 JI) [x86_64-apple-darwin10.4.0]
$ rbx prime_fast.rb
Found 183072 in the numbers from 0 to 2500000 in 1.277507s

JRuby 1.5.6:
$ java -Xmx1024m -jar Downloads/jruby-complete-1.5.6.jar prime_fast.rb
Found 183072 in the numbers from 0 to 2500000 in 1.804s

Nice to see rubinius up there :)

local entryjid, name = line:match("([^=]*)=?(.*)");

This assigns a value to the two variables according to the matches that the regular expression returns.
So to have the names injected, the groups.txt file has to have the JID and the name seperated by an equals sign. So this is what the format looks like:

username@jabberserver.com=John Doe  
anothername@jabberserver.com=Jane Doe  

This way, you can inject jids AND names :)

$ lpstat -a

and then printing the files using (in my case: a bunch of jpeg files):

lp -d "my_printer_name" *.jpg

If you just want to use the default printer, you can leave away the -d option.