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My Nokia phones can do it, so I thought there must be a way to do it on my laptop too. I wanted a way to scan both "traditional" barcodes and "two-dimensional" ones, like the QR-Codes. Here is my solution.

You'll need :

- a v4l-compatible webcam + mplayer compiled with v4l support (or any other scriptable way to grab frames from the webcam)

- a scriptable image viewer, I use feh on my laptop

- ZXing

Follow the instructions to build the ZXing javase component, then open three shell windows, and run:

shell1 (grab the webcam output as last.jpg +- every half second):

cd /tmp ; while [ 0 ] ; do mplayer tv:// -fps 2 -tv driver=v4l:width=640:height=480:device=/dev/video0 -vo jpeg:quality=95 -frames 2 ; mv 00000001.jpg last.jpg ; done

shell2 (view what you grabbed):

cd /tmp ; feh -R 1/2 last.jpg

shell3 (scan for barcodes):

while [ 0 ] ; do ( java -cp javase/javase.jar:core/core.jar com.google.zxing.client.j2se.CommandLineRunner /tmp/last.jpg | fgrep -v 'No barcode found') ; sleep 1 ; done

So no nice GUI, but it seems to work well.

I wanted to try the new 2.6.25 kernel on a Sunblade 100 I'm reinstalling. But immediately after entering "make" I got the following error:

arch/sparc64/kernel/asm-offsets.c:1: error: -m64 is not supported by this configuration
arch/sparc64/kernel/asm-offsets.c:1: error: -mlong-double-64 not allowed with -m64
arch/sparc64/kernel/asm-offsets.c:1: error: -mcmodel= is not supported on 32 bit systems
make[1]: *** [arch/sparc64/kernel/asm-offsets.s] Error 1
make: *** [prepare0] Error 2

I found the solution here, along with the explanation. To make it short, to get it to work, for now you'll have to type:

 # CROSS_COMPILE=sparc64-unknown-linux-gnu- make

It seems that after having been up for a couple of days, the WAG200G starts having issues routing UDP packets properly. This particularly affects VoIP traffic (here IAX2 on port 4569). The symptoms are that "regular surfing" works flawlessly, but the registration with the asterisk server fails. tcpdump shows no traffic on the server side. Restarting the WAG200G immediately solves the problem.

Here is how I restarted the router from the command line:

wget --http-user=admin --http-password=pa55w0rd \
     --post-data='reboot=1&save=Enregistrer+les+param%E8tres&todo=reboot&h_reboot=1&this_file=Reboot.htm&next_file=index.htm&message=' \
     http://192.168.0.1/setup.cgi

(replace password and IP address as appropriate)

Tonight I installed my first diskless Ubuntu system. The version I used is the latest available as of today, 7.04 "FeistyFawn". This article covers the client part.

My other diskless machines all run Gentoo (for the time being). I've described previously how I set up my SB 100, the rest of the setup was based on this article.

The following two articles were helpful:

https://help.ubuntu.com/community/Installation/OnNFSDrive
http://developer.novell.com/wiki/index.php/Feisty/HOWTO:_Convert_Ubuntu_to_Diskless

However I found some of the info to be uncomplete or outdated.

From what I have read, unlike with Gentoo, it seems that there is no easy way to get a working diskless Ubuntu system directly. Instead, you have to install to a disk first, and then make your setup diskless. I did not really want to open the box, so I tried first to install on a 2 GB CF card, which didn't work because the card was full before the install completed (du now reports that the system is 2.1 GB big). So I ended up putting a disk in the box, and I ran a regular install.

Note: As in the SB100 article, 10.0.0.10 will be my dhcp/nfs/tftp server ('fileserver'). 10.0.0.30 will be the Ubuntu desktop.

Once that was completed, instead of rebooting as suggested by the installer, I opened a shell (gnome-terminal), and ran:

sudo su -

mkdir /mnt/tmp

mkdir /mnt/nfs

mount /dev/sda1 /mnt/tmp

mount 10.0.0.10:/diskless/ubuntu /mnt/nfs

cp -a /mnt/tmp/* /mnt/nfs/

After that, there are just a couple of things that need to be changed:

chroot /mnt/nfs

mount -t proc proc proc

vi etc/initramfs-tools/initramfs.conf

and make sure you have:

BOOT=nfs

then run:

update-initramfs -u

Now check what you have in /boot, and update your network boot config files accordingly. I use pxegrub, and here is how /boot/grub.lst looks like:

default 0

timeout 10

title=Diskless Ubuntu

root (nd)

kernel /diskless/tv/boot/vmlinuz-2.6.20-15-generic ip=dhcp root=/dev/nfs nfsroot=10.0.0.10:/diskless/tv ro quiet splash

initrd /diskless/tv/boot/initrd.img-2.6.20-15-generic

Finally, don't forget to update etc/fstab and etc/network/interfaces. I've read several theories, here is what worked for me:

fstab:

# /etc/fstab: static file system information.

#

#                

proc            /proc           proc    defaults        0       0

/dev/nfs        /               nfs     defaults        0       0

/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto     0       0

network/interfaces:

auto lo

iface lo inet loopback



auto eth0

iface eth0 inet static

        address 10.0.0.30

        netmask 255.255.255.0

        network 10.0.0.0

        broadcast 10.0.0.255

        gateway 10.0.0.1

(note: commenting out eth0 as suggested in some places made the system hang during the boot process.)

Lightning is a Thunderbird plug-in that adds calendar functions. More on the mozilla.org page. I tried to install the .xpi from there, but it failed with the following error message:

"Lightning" could not be installed because it is not compatible with your Thunderbird build type (Linux_x86_64-gcc3). Please contact the author of this item about the problem.

So I downloaded the source from this page, and followed the instructions from here. This page and the link to that one were also helpful.

In case you don't want to open all those links, I've put the resulting .xpi file here for you to download: lightning-0.3.1-x86_64.xpi. Or if you prefer to build it yourself, here is how I did it:

[untar/bz, cd mozilla]
make distclean
export CFLAGS="-O2 -pipe -fPIC"
export CHOST="x86_64-pc-linux-gnu"
export CXXFLAGS="${CFLAGS}"
export MAKEOPTS="-j3"
ac_cv_visibility_pragma=no ./configure --enable-application=mail --enable-extensions=default,lightning
make

(of course you may want to change some stuff to better suit your system, I've got a Core 2 Duo laptop running Gentoo Linux)

Then just select Tools > Extensions in Thunderbird and install the lightning.xpi you've just built (located in dist/xpi-stage/lightning.xpi).


UPDATE - 2007-06-28 - Lightning 0.5

After reading Matthew's comment I downloaded the newly released Lightning 0.5 from here, and built lightning-0.5-x86_64.xpi following the exact same procedure that I used for 0.3.1. Then I installed it from Tools > Extensions, restarted Thunderbird and immediately noticed the different appearance. (I did not uninstall 0.3.1 first, which apparently is ok.)

UPDATE - 2008-09-28 - Lightning 0.9

Download from http://releases.mozilla.org/pub/mozilla.org/calendar/lightning/releases/0.9/contrib/linux-x86_64/