Damn it, it doesn't work ...

tftp-hpa setup instructions on mac

2010-11-13T15:01:00.001+01:00

Just for backup purposes as I need this tftp server only on-demand:

***** Setup Instructions *****

NOTE: By default, tftp-hpa listens to the tftp port specified in /etc/services (port 69)
on all local addresses.

To run tftpd manually for download only access, use this command:
sudo tftpd -L -s

To run tftpd manually and support tftp uploads, add "-c" to the command:
sudo tftpd -L -c -s

You may run tftpd at system boot using the startupitem if you installed tftp-hpa
using the server variant. To load the startupitem using launchctl:
sudo launchctl load -w /Library/LaunchDaemons/org.macports.tftpd.plist

NOTE: When loading tftp-hpa using launchctl, make sure to place the files you want to serve
in /opt/local/var/tftp-hpa/, because that is the location set in the StartupItem.

*******************************

If you wish to run tftpd in inetd mode, you may make an inetd compatible .plist
file and replace the one installed by MacPorts in /Library/LaunchDaemons. You
may use /System/Library/LaunchDaemons/tftp.plist as a template.

cpufreq on debian lenny

2010-05-23T14:17:00.002+02:00

First, check whether you already have cpu frequency scaling enabled by running cpufreq-info:

# cpufreq-info cpufrequtils 004: cpufreq-info (C) Dominik Brodowski 2004-2006 Report errors and bugs to cpufreq@lists.linux.org.uk, please. analyzing CPU 0: driver: acpi-cpufreq CPUs which need to switch frequency at the same time: 0 hardware limits: 600 MHz - 1.70 GHz available frequency steps: 1.70 GHz, 1.40 GHz, 1.20 GHz, 1000 MHz, 800 MHz, 600 MHz available cpufreq governors: conservative, userspace, powersave, ondemand, performance current policy: frequency should be within 600 MHz and 1.70 GHz. The governor "ondemand" may decide which speed to use within this range. current CPU frequency is 600 MHz (asserted by call to hardware). cpufreq stats: 1.70 GHz:4.56%, 1.40 GHz:0.18%, 1.20 GHz:0.00%, 1000 MHz:0.21%, 800 MHz:0.18%, 600 MHz:94.86% (10)

If you do not have an output like the one above, you need to configure your cpufreq-stuff. If you do not have cpufreq-info installed, run

apt-get install cpufrequtils sysfsutils

Afterwards, you have to load your cpu scaling manager. I usually use acpi_cpufreq:

modprobe acpi_cpufreq

Afterwards, you need to decided the policy manager. See this previous entry for more information.

You can use cpufreq_ondemand for example:

modprobe cpufreq_ondemand

Finally, you have to enable the frequency scaling by enabling the governor:

echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

To make things permanent, you can run:

echo acpi_cpufreq >> /etc/modules
echo cpufreq_ondemand >> /etc/modules
echo "devices/system/cpu/cpu0/cpufreq/scaling_governor = ondemand" >> /etc/sysfs

XCode: 1 source file parsed, no classes found or changed

2010-03-06T14:25:00.002+01:00

The XCode Cocoa Application Tutorial states that one has to create a controller class (ConverterController in this tutorial). This controller needs to be included into the Interface Builder (IB) by "Open->Read Class File".

If this is done, there will be an error in the MainMenu XIB/NIB-Window that says: "1 source file parsed, no classes found or changed".

I'm not sure what the problem is (maybe there was a change for Snow Leopards and XCode 3.2.1), but I found a way on how to import the Class file. You need to select "Tools->Library" and select the "Classes" tab in the Library window. You will find the ConverterController class in this list. Double-Click it and the class will appear in your MainMenu.xib

New Window, New Frame

2010-02-03T09:03:00.002+01:00

Create a new window with emacs:

C-x 4 b

Close the window:

C-x 4 0

New frames can be created with C-x 5 b ...

Emacs: Evaluating expressions

2010-02-02T13:11:00.003+01:00

Use M-: to evaluate a single elisp expression. You can use this for example for setting variables. For example: If you enabled the mode auto-fill (M-x auto-fill-mode), the default wrap value for your lines is set to 70.

You can then use M-: to reset this to a more sane value by entering

(setq fill-column)

into the minibuffer.

Macports: Installing gtk-doc

2010-01-30T15:06:00.002+01:00

Installing gtk-doc from macports failed on my system due to problems with these configure errors:

king for xsltproc... /opt/local/bin/xsltproc
checking for dblatex... no
checking for fop... no
configure: WARNING: neither dblatex nor fop found, so no pdf output from xml
checking for XML catalog (/opt/local/etc/xml/catalog)... found
checking for xmlcatalog... /opt/local/bin/xmlcatalog
checking for DocBook XML DTD V4.3 in XML catalog... not found

This seems to be a problem with the installation of the docbook packages. It was necessary to add the following nextCatalog tags into the catalog:

<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
<nextCatalog catalog="/opt/local/share/xml/docbook/5.0/catalog.xml"/>
<nextCatalog catalog="/opt/local/share/xml/docbook/4.3/catalog.xml"/>
</catalog>

Afterwards, a new error occured:

king for xsltproc... /opt/local/bin/xsltproc
checking for dblatex... no
checking for fop... no
configure: WARNING: neither dblatex nor fop found, so no pdf output from xml
checking for XML catalog (/opt/local/etc/xml/catalog)... found
checking for xmlcatalog... /opt/local/bin/xmlcatalog
checking for DocBook XML DTD V4.3 in XML catalog... found
checking for DocBook XSL Stylesheets in XML catalog... not found
configure: error: could not find DocBook XSL Stylesheets in XML catalog

This could be fixed by adding another nextCatalog tag:

<nextCatalog catalog="/opt/local/share/xsl/docbook-xsl/catalog.xml"/>

Ignore Joins and parts on irssi

2009-12-23T21:40:00.002+01:00

/ignore #channelname[,#channel2] JOINS PARTS

ignores JOIN- and PART messages.

Restoring and dumping postgresql databases

2009-12-07T17:04:00.004+01:00

Dump a database:

pg_dump [-U ] database-name | gzip > database.gz

Restore a database:

gunzip < database.gz | psql -f - [-U ] database-name

Installing PostgreSQL on FreeBSD

2009-12-07T13:43:00.003+01:00

You can install postgresql from the ports:

cd /usr/ports/database/postgresql84-server
make install clean

The master user for the database on FreeBSD, in contrast to the master user on most Linux distributions, is called pgsql. Hence, you have to initialize the database using this user:

su - pgsql

Run

initdb -D /usr/local/pgsql/data
postmaster -D /usr/local/pgsql/data

to finish the initialization. In order to start postgres on boot, you need to add

postgresql_enbale="YES"
postgresql_data="/usr/local/pgsql/data

into your /etc/rc.conf.

XDM listening on port 6000

2009-12-04T15:01:00.002+01:00

XDM has the annoying behavior to start an Xserver which is listening on port 6000 for incoming TCP connections. If you want to turn this feature off, you need to edit the xdm config files. On FreeBSD (8), this file can be found at

/usr/local/lib/X11/xdm/Xservers

Change

:0 local /usr/local/bin/X :0

:0 local /usr/local/bin/X :0 -nolisten tcp

Reverting a commit in Subversion

2009-11-27T13:29:00.002+01:00

I had to revert parts of an SVN commit (and didn't want to perform a long lasting git-checkout of the given repository). I found some nice information about the task in this blog post.

Creating a DOS usb stick on Linux

2009-11-19T09:41:00.005+01:00

As hardware usually is shipped broken, it is often necessary to update the crappy software on these broken devices with a firmware update. Some vendors have Linux/Unix tools for this task, but most only have fireware update "tools" which need to be run from DOS.

This is a big problem for me, as I do neither use DOS or Windows on my machines. Setting up a FreeDOS boot stick from Linux can be a difficult task. There are some tutorials on how to do this on the net. However, most of them did not work for me, i.e. the stick would not boot.

The only tutorial which really worked was one from wiki.fdos.org. More exactly, the using "Using balder10 and qemu under Linux" was the only thing that worked for me:

You need to install dd and qemu on your system. Then, download the balder10.img, which is a FreeDOS image.

Plug in your USB stick and find the device name. You can check dmesg for that. You can also erase the MBR on the stick by running

dd if=/dev/zero of=/dev/ bs=1024 count=2

as written on wiki.fdos.org. However, I do not think this is necessary.

Boot the balder10.img using qemu with:

qemu -boot a -fda ./balder10.img -hda /dev/sdc

This will boot from the image and mounts the image at A: and your Stick as C: (if it has a FAT partition on it. If it does not have a FAT partition, you need to create one using fdisk on the image. If you have created a new partition, you need to reboot qemu in order to make the changes visible to Dos. Afterwards, you can create the DOS image by running

format C: /s
xcopy A: C: /N /E

which will create a DOS files ystem on your stick and will also create the boot records. You can now boot from your USB stick.

When I booted from my stick, the partition on the stick appeared at C:. However, the Dos image expects to boot from A: and will set all PATHS to point to drive A:. If you have the same problem, check every .BAT file on your stick for the string A: and replace it with C:. This will fix your problems.

Disable IPv6 using sysctl on Linux

2009-11-02T09:55:00.003+01:00

Run

sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1
sysctl -w net.ipv6.conf.lo.disable_ipv6=1

on the command line to disable it immediatelly (you might need to put all interfaces down and up in order to loose your IPv6 addresses on the interface). The changes will not be permanent and will be lost on reboot. If you need to make them permanent add

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

to your /etc/sysctl.conf.

How to copy a virtual box image

2009-10-22T08:36:00.002+02:00

Make sure the image is not used by any virtual machine, then run

VBoxManage clonehd

if the corresponding image is in your virtualbox directory (usually /home//.Virtualbox/HardDisks) or

VBoxManage clonehd /path/to/your/image.vdi /desired/location/of/your/image.vdi

Reload Snort Rules

2009-10-20T10:12:00.004+02:00

Did you know? You can load a new rule set into snort without restarting snort. Simply send the HUP signal to the running snort instance and it will parse its config file and load new rules:

killall -HUP snort

Xen DomU - Boot in Single User Mode

2009-10-08T13:28:00.002+02:00

Add

extra = 'single'

to the xen domU config file

Postfix: Configuring Smarhost with TLS and Authentication

2009-08-03T18:20:00.005+02:00

Configuring mutt as you mail client does force you to configure a mail server on you local system, as mutt cannot send mails by itself. When I chose to use mutt, I decided to set up postfix to drop my sent mail to my usual mailserver. This mailserver does run on port 465, uses TLS and needs authentication.

Therefore, I added

relayhost = <somehost>.<somedomain>.de:465
smtp_sasl_auth_enable = yes
smtp_use_tls = yes
smtp_enforce_tls = yes
smtp_sasl_password_maps = hash:/etc/postfix/smtp_sasl_passwords
smtp_tls_per_site = hash:/etc/postfix/smtp_tls_sites

to my /etc/postfix/main.cf. Most of the configuration options are self-explaining. We can see that mail should be sent through ≶somehost>.<somedomain>.de using tls and sasl_auth. Sasl_auth is used to provide authentication to the mailserver.

It will read its usernames and passwords from the sasl_database create from /etc/postfix/smtp_sasl_passwords. You need to create this file (and make it read only for root, as it does contain your password in plain text). This file contains password in the following form:

<somehost>.<some-domain>.<some-top-level-domain> <some-username>:<some-password>

After you created that file, you need to run postmap /etc/postfix/smtp_sasl_passwords, which will create /etc/postfix/smtp_sasl_passwords.db for you.

If your smtp-server does not have a self-signed certificate, you need to create /etc/postfix/smtp_tls_sites which needs to contain

<somehost>.<some-domain>.<some-top-level-domain> MUST_NOPEERMATCH

Afterwards, you need to run postmap on this file again. Start postfix afterwards and check /var/log/mail.log for any errors (or successful startup).

pkg_add via HTTP

2009-07-06T18:27:00.002+02:00

If you want to install FreeBSD packages via HTTP (e.g. because your firewall does not allow FTP), you need to set PACKAGESITE to a repository which distributes the packages via HTTP. For example:

setenv PACKAGESITE http://ftp2.de.freebsd.org/pub/FreeBSD/ports/i386/packages-7-stable/Latest/

Only TFTP with FreeBSDs pxeboot

2009-07-06T18:05:00.003+02:00

The FreeBSD pxeboot binary wants to include the loader from a NFS share. If mounting the share fails, the system will halt and needs a hard reboot. In order to propagate the loader via TFTP you need to recompile the binary. Therefore, you will have to install the FreeBSD sources and edit your /etc/make.conf. Insert

LOADER_TFTP_SUPPORT=YES
LOADER_NFS_SUPPORT=NO

into the file. This will make pxeboot to be compiled without NFS and with TFTP support. Then change into

/usr/src/sys/boot/i386/pxeldr

and make the sources. A new file pxeboot will appear, which is able to load the loader via TFTP. One very annoying thing still happens with the new pxeboot (at least till 7.2): Pxeboot will still try to mount the NFS share and will get the loader after the NFS timeout occured (60 seconds on my systems).

FreeBSD 8-CURRENT with more than 16 user groups

2009-06-23T19:34:00.003+02:00

After I csuped to the latest CURRENT-Source and had a quick look at /usr/src/UPDATING I found this entry:

20090619:
NGROUPS_MAX and NGROUPS have been increased from 16 to 1023
and 1024 respectively. As long as no more than 16 groups per
process are used, no changes should be visible. When more
than 16 groups are used, old binaries may fail if they call
getgroups() or getgrouplist() with statically sized storage.
Recompiling will work around this, but applications should be
modified to use dynamically allocated storage for group arrays
as POSIX.1-2008 does not cap an implementation's number of
supported groups at NGROUPS_MAX+1 as previous versions did.

NFS and portalfs mounts may also be affected as the list of
groups is truncated to 16. Users of NFS who use more than 16
groups, should take care that negative group permissions are not
used on the exported file systems as they will not be reliable
unless a GSSAPI based authentication method is used.

This is really great news!

Add user to unix group

2009-04-29T14:28:00.003+02:00

I used to add users to a new unix group by firing up my favorite editor and edit /etc/group. That's because I always forget which tool to use and how to use it. This blog posting shall remind me of usermod:

usermod -a -G <groupname>[,<groupname>,...] <username>

Mercurial on Mac OS X: ValueError: unknown locale: UTF-8

2009-04-11T19:26:00.004+02:00

Mercurial from macports on Mac OX X Leopard gives this error message on any hg command:

Traceback (most recent call last):
File "/opt/local/bin/hg", line 25, in
mercurial.util.set_binary(fp)
File "/opt/local/lib/python2.5/site-packages/mercurial/demandimport.py", line 75, in __getattribute__
self._load()
File "/opt/local/lib/python2.5/site-packages/mercurial/demandimport.py", line 47, in _load
mod = _origimport(head, globals, locals)
File "/opt/local/lib/python2.5/site-packages/mercurial/util.py", line 93, in
_encoding = locale.getlocale()[1]
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/locale.py", line 462, in getlocale
return _parse_localename(localename)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/locale.py", line 375, in _parse_localename
raise ValueError, 'unknown locale: %s' % localename
ValueError: unknown locale: UTF-8

The mercurial-user list has a posting from October 2007 that blames the Mac OS X terminal application.

This really seems to be a problem with the terminal application, because if you start X11 and xterm, hg will start without the error message. In order to work with mercurial on Terminal you need to set LC_ALL and LANG in your .bashrc or .profile, like

export LC_ALL=en_US.UTF-8
export LANG=en_US.UTF-8

nfsen-1.3 on debian lenny

2009-04-01T10:14:00.003+02:00

Lenny ships with rrdtools version 1.3 which is not supported by nfsen-1.3 (the latest stable version of nfsen). One needs to patch the source code in order to install nfsen


--- libexec/NfSenRRD.pm.old 2009-04-01 10:21:54.000000000 +0200
+++ libexec/NfSenRRD.pm 2009-04-01 10:11:18.000000000 +0200
@@ -73,7 +73,7 @@
  if ( $rrd_version < 1.1 ) { # it's RRD 1.0.x
   $RRDoffset = 77;
  }
- if ( $rrd_version >= 1.2 && $rrd_version < 1.3 ) {
+ if ( $rrd_version >= 1.2 && $rrd_version < 1.4 ) {
   $RRDoffset = 67;
  }

Caps -> Control with xmodmap

2009-03-25T19:04:00.002+01:00

There was a post on my blog in August 2008, where I described how to change the caps key into control on via Xorg configuration files.

This is nice and handy if you have control over you xorg.conf. But it will not work, if you don't have that control (or if you don't have such a file). You can use xmodmap insteed. Create the file .xmodmap in your home directory and put the lines

clear Lock
remove Control = Control_L
keycode 66 = Control_L
add Control = Control_L

into the file. In order to change the key settings you need to run xmodmap /.xmodmap

domU doesn't start after update to lenny

2009-02-17T11:23:00.003+01:00

As stated in the previous post, I upgraded several machines to lenny. These machines are virtualized via xen. After the upgrade none of the installation did boot correctly. They stopped right after

INIT: Entering runlevel: 2
Starting system log daemon....
Starting kernel log daemon....
Starting system message bus: dbus.
Starting OpenBSD Secure Shell server: sshd[ 19.189974] NET: Registered protocol family 10
[ 19.190697] lo: Disabled Privacy Extensions
.
Not starting internet superserver: no services enabled.
Starting periodic command scheduler: crond.

To fix this problem, you need to boot them into single user mode (add extra="single" to your domU configuration file) and add

hvc0:23:respawn:/sbin/getty 38400 hvc0

to /etc/inittab

Update to Lenny

2009-02-17T09:41:00.002+01:00

I have several debian machines that want to be upgraded from etch to lenny. After changing /etc/apt/sources.list to the new stable version and running apt-get update I got this message:

# apt-get update
Get:1 http://security.debian.org stable/updates Release.gpg [189B]
Get:2 http://ftp.de.debian.org lenny Release.gpg [386B]
Hit http://security.debian.org stable/updates Release
Hit http://ftp.de.debian.org lenny Release
Ign http://security.debian.org stable/updates/main Packages/DiffIndex
Ign http://security.debian.org stable/updates/contrib Packages/DiffIndex
Ign http://ftp.de.debian.org lenny/main Packages/DiffIndex
Ign http://security.debian.org stable/updates/non-free Packages/DiffIndex
Ign http://security.debian.org stable/updates/main Sources/DiffIndex
Ign http://security.debian.org stable/updates/contrib Sources/DiffIndex
Ign http://security.debian.org stable/updates/non-free Sources/DiffIndex
Hit http://security.debian.org stable/updates/main Packages
Ign http://ftp.de.debian.org lenny/contrib Packages/DiffIndex
Ign http://ftp.de.debian.org lenny/non-free Packages/DiffIndex
Ign http://ftp.de.debian.org lenny/main Sources/DiffIndex
Ign http://ftp.de.debian.org lenny/contrib Sources/DiffIndex
Ign http://ftp.de.debian.org lenny/non-free Sources/DiffIndex
Hit http://security.debian.org stable/updates/contrib Packages
Hit http://security.debian.org stable/updates/non-free Packages
Hit http://security.debian.org stable/updates/main Sources
Hit http://security.debian.org stable/updates/contrib Sources
Hit http://ftp.de.debian.org lenny/main Packages
Hit http://security.debian.org stable/updates/non-free Sources
Hit http://ftp.de.debian.org lenny/contrib Packages
Hit http://ftp.de.debian.org lenny/non-free Packages
Hit http://ftp.de.debian.org lenny/main Sources
Hit http://ftp.de.debian.org lenny/contrib Sources
Hit http://ftp.de.debian.org lenny/non-free Sources
Fetched 2B in 0s (13B/s)
Reading package lists... Done
W: There is no public key available for the following key IDs:
4D270D06F42584E6
W: You may want to run apt-get update to correct these problems

To fix this problem you need to

# apt-get install debian-keyring debian-archive-keyring
# apt-key update
# apt-get update

and the message will disappear.

Merging pcap files

2009-01-08T15:30:00.002+01:00

Today I wanted to merge several pcap files into one bigger file. Mergecap which is shipped with wireshark seemed to be a good tool for that task.

Since the pcap files where scattered into several directories under traces_files/, I needed to use find to gather all the file names. When trying to merge them together using

mergecap -w worms.pcap $(find ./ -name "*.pcap")

there was an error message:

mergecap: Can't open .//dir/file.pcap: Too many open files

If you do encounter that problem, you should check your open files limit with ulimit -n. Increase that value with ulimit -n <new number>.

CMake: Find libraries in custom install places

2008-12-15T10:23:00.003+01:00

If you want cmake to find libraries that are not installed within the default locations (because you installed it using --prefix=/my/special/installpath), you need to tell cmake about this path.

This is done via the cmake variable CMAKE_PREFIX_PATH. You can set it with

cmake -DCMAKE_PREFIX_PATH=/my/special/installpath .

and it will search /my/special/installpath for all of your libraries first. You can also specify more than one path:

cmake -DCMAKE_PREFIX_PATH=/my/special/installpath:/my/second/special/installpath .

Padding pcap files

2008-11-27T11:47:00.002+01:00

When recording network traffic (e.g. with tcpdump) only n bytes (the snaplen) are recorded. If the snaplen is shorter than the packet size, you will have truncated packets in you dump file.

If you do have such a pcap file and you need the packets to have the size that is specified in the IP header, then you can use tcprewrite to pad the data. tcprewrite is part of the tcpreplay program suite:

tcprewrite --infile in.pcap --outfile out.pcap -F pad

Snort and big pcap files

2008-11-26T14:44:00.002+01:00

Snort isn't able to read large pcap files (> 2GB) if you compile it with

$ ./configure
$ make
$ make install

Even if the libpcap shipped with your distribution is able to read big files. The snort source does need to be compiled with the compile time opions _LARGEFILE_SOURCE, _LARGEFILE64_SOURCE and _FILE_OFFSET_BITS=64. You can enable these flags by setting the environment varible CFLAGS

$ CFLAGS="-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64" ./configure
$ make
$ make install

Mounting Samba-Shares on Mac OS X

2008-11-18T14:37:00.005+01:00

You can use Finder to mount the samba share. If the share is available via broadcast within the local subnet, you should see the fileserver in the left side of the window under "SHARED". Click on the Server, choose "Connect as", insert your username and password and choose the share you want to mount.

If your samba server is not in the same subnet, it will not appear as an item in the "SHARED" section of your finder windows. You therefore need to specify the share location by hand. Use the key combo

Command + K

for that. A window will pop up and ask you for the server location.

You need to specify the protocol and the host like in the picture above. If you are connected, the server will ask you for your login name and you password and will present you a window with the available volumes. Click on one of them and you are done.

When tcpdump drops to many packets ....

2008-11-12T16:50:00.003+01:00

I had a machine within a gigabit ethernet environment and tried to check the network traffic with

tcpdump -i eth0

The outcome was staggering:

45 packets captured
7509 packets received by filter
7392 packets dropped by kernel

This is quite a high packet loss rate. After some "debugging" I found that tcpdump tries to look up the domain names for all the IP addresses it sees. So therefor it's necessary to use the -n option:

tcpdump -i eth0 -n

does result in

27105 packets captured
29008 packets received by filter
1893 packets dropped by kernel

This is better but there is still some packet loss left due to tcpdump writing all it's output to the terminal. If you do use a slow painting terminal (like the KDE konsole), then you will see quite a high packet loss. In order to avoid this, you must redirect the output to file using

tcpdump -i eth0 -n > output.txt

which does result in

43332 packets captured
43332 packets received by filter
0 packets dropped by kernel

Booting into single user mode

2008-09-26T11:13:00.002+02:00

Linux and Grub:

Add "single" to the kernel command line

FreeBSD loader:

Set variable "boot_single"

IPv6 link local

2008-09-18T17:50:00.002+02:00

One should think that getting an IPv6 link local address is an easy task. Since it can be calculated by the kernel, it should appear when configuring an ipv6 address.

Well, that's what i thought ... but someone decided that the linux kernel only assigns a link local addresses, when the network cable is plugged in during interface configuration. One hour well spent ...

Changing the Cursor in X

2008-09-11T10:09:00.003+02:00

There was a post on bsdforen.de asking for how to change the default cursor from the X-Server to the normal left arrow that is used by most of the window manager.

Dr. Google told me, that the answer to that question is

xsetroot -cursor_name left_ptr

But I could not find a list of possible values for -cursor_name ... But xsetroot is open source ...

Xsetroot uses libXmu to set the cursor. This library contains a list of possible cursor names in src/CursorName.c:

x_cursor
arrow
based_arrow_down
based_arrow_up
boat
bogosity
bottom_left_corner
bottom_right_corner
bottom_side
bottom_tee
box_spiral
center_ptr
circle
clock
coffee_mug
cross
cross_reverse
crosshair
diamond_cross
dot
dotbox
double_arrow
draft_large
draft_small
draped_box
exchange
fleur
gobbler
gumby
hand1
hand2
heart
icon
iron_cross
left_ptr
left_side
left_tee
leftbutton
ll_angle
lr_angle
man
middlebutton
mouse
pencil
pirate
plus
question_arrow
right_ptr
right_side
right_tee
rightbutton
rtl_logo
sailboat
sb_down_arrow
sb_h_double_arrow
sb_left_arrow
sb_right_arrow
sb_up_arrow
sb_v_double_arrow
shuttle
sizing
spider
spraycan
star
target
tcross
top_left_arrow
top_left_corner
top_right_corner
top_side
top_tee
trek
ul_angle
umbrella
ur_angle
watch
xterm

XForwarding and FreeBSD

2008-09-09T14:28:00.004+02:00

It is not possible to use X-Forwarding into a stock FreeBSD machine, after you installed the xorg-server port. Even when /etc/ssh/sshd_config says that XForwarding is enabled. I tried this and did not get a DISPLAY variable.

And there was no error message at all. Searching the web did not reveal any results. The key to the solution was the ssh verbose mode. One line told about the xauth utility missing.

If you have a similar problem, then try to install x11/xauth from the ports. This should solve your problems.

Changing default application for files

2008-08-28T10:51:00.003+02:00

You can change the default application for opening a given file type on Mac OS X with Finder. Just mark a file (e.g. a PDF file), Press Command + i (or choose File->Get Info from the menu) and change "Open with" to your desired application. Then press the "Change all" button.

Turn Caps into Control

2008-08-25T20:29:00.003+02:00

While configuring an X-Server, there is the possibility to turn off the caps lock key and use it as control key insteed by adding

Option "XkbOptions" "ctrl:nocaps"

into the "Input Device" section in /etc/X11/xorg.conf. But Mac OS X does not have any xorg.conf for it's graphical interface. A way to perform the same configuration on Leopard is to use the system settings application. The "Keyboard & Mouse" tab contains a button named "Modifier Keys..." in the keyboard tab. This button will open a window that does allow to bind the keys "Caps Lock", "Control", "Option" and "Command" to different functionalities. Use this dialog to change your settings accordingly.

git and svn on Mac OS X

2008-07-28T17:33:00.003+02:00

Hmm, run into the first problem when installing a macports port: Git was installed without svn support even after svn was installed before. In order to fix the problem I needed to install the port with

port install git-core +svn

which pulled in all the dependencies and created git with svn support.

Installing third party applications on the Mac

2008-07-28T16:58:00.003+02:00

Some time ago, I blogged about my new Mac and Gentoo prefix. Back then Gentoo Prefix seemed to be a good idea. But after some time using it, it seems like all the stuff I need for my work isn't really working. Since I have limited time at the moment, there is no way I can run the prefix installation in my day to day work.

I'm now evaluating MacPorts. This project should work better, since they purely concentrate on porting third party software to the Mac. The essential tools for my work seem to compile fine (still compiling at the moment).

Maybe I can manage to compile VERMONT by tomorrow on Mac OS X :-) (though I assume that VERMONT needs some porting ...)

Ext2/ext3 problems on FreeBSD

2008-07-21T17:03:00.004+02:00

Creating and mounting an ext2/ext3 filesystem shouldn't be a problem. At least that's what one should expect. But there can be a problem, as I've seen today.

If you create the filesystem with mkfs.ext2 from the ports, than there will be a file system that has a default inode size of 256 Bytes. But the FreeBSD ext2fs kernel module cannot handle them as of now.

If you mount the newly created file system (e.g. at /home), there will be no error message. But if you try to access the filesystem there will be the message

ls: /home: Bad file descriptor

You need to create a filesystem with the old 128 byte sized inodes with

mkfs.ext2 -I 128 /dev/

in order to mount it with FreeBSD. If you want to check how big the inode size on your ext-partition is, then you can use

tune2fs -l /dev/ | grep Inode

Turn off link prefetching

2008-07-18T15:24:00.002+02:00

Firefox can prefetch websites that are linked on the site that you currently look at. If you don't want that, then you can open

about:config

in your browser and search for

network.prefetch-next

and turn it to false.

If your firefox is closed, you can add the line

user_pref("network.prefetch-next", false);

to $firefox-profile/prefs.js or $firefox-profile/user.js insteed.

Another feature that you might want to block is sending the referer. If you click on a link on website www.a.com that referes to website www.b.com with the referer feature enabled, then website www.b.com will know that you last visited website www.a.com. If you don't like that you can turn the option

network.http.sendRefererHeader

to 0 in about:config or change the option in prefs.js or user.js accordingly.

33 years old bug in yacc

2008-07-09T09:45:00.002+02:00

The OpenBSD journal had a nice story about a bug in yacc. The most interesting part is

Funny thing is that I traced this back to Sixth Edition UNIX, released in 1975. A very similar problem can be spotted here. The lines:

So it is 8 years older than the 25 year old bug in seekdir that was found in May 2008 :-)

YZis 1.0-alpha1 is out

2008-06-26T09:53:00.002+02:00

After a long time of development stale, Thomas Capricelli announced that he's going to do some development again.

He moved the source code to mercurial, closed the old bugs and prepared for an initial release. Today he announced the first alpha release of version 1.0.

Howto write FreeBSD kernel modules

2008-06-25T14:19:00.004+02:00

The FreeBSD webpage contains a link to an interesting introduction on how to write kernel modules. It's a very good starting point if you plan to write a module or if you want to read an existing modules code. You can find the article at

http://www.freesoftwaremagazine.com/articles/writing_a_kernel_module_for_freebsd

Have fun

New to Mac OS X

2008-06-15T17:41:00.003+02:00

I started my PhD studies last Monday at the Technical University of Munich last month. After my arrival the admin gave me an iBook to experiment with. The positive thing about it is that it "just works". But there is a lack of useful tool that i got used to from GNU/Linux or *BSD. But there is a solution to that problem:

http://www.gentoo.org/proj/en/gentoo-alt/prefix/

A Gentoo overlay on the Mac. It's now emerging on the laptop and I'm quite curious about the results.

Mounting a file on FreeBSD

2008-06-04T12:17:00.000+02:00

I always forget how to mount a file or how to create a file system in a file on FreeBSD. Therefore this post. There is no "-o loop" option for mount like it is on GNU/Linux. Insteed you need to manually create a device that binds the file to the device system. You can do this via

mdconfig -f <file_name>

This will bind the file to the device /dev/md0 (or the first free /dev/mdX device). You then can operate on that device like on an ordinary device. You might have to load the kernel module before. In order to clean up run

mdconfig -d -u <device_numer>

where <device_numer> is the number of the md device you want to remove.

Pidgin and SSL/TSL certificates

2008-06-03T13:52:00.002+02:00

I updated to pidgin version 2.4.2 and got problems with my jabber account. This is due to me using TSL/SSL encrypted connections. Pidgin thinks that the used certificate is not valid. One needs to manually import it to pidgin. This is described in several tutorials on the net:

Use openssl to get the certificate. You need to run

openssl s_client -connect <your_jabber_server_here>:5223

Abort openssl using Strg+C after the startup. Openssl will print the lines

-----BEGIN CERTIFICATE-----
lots of stuff...
-----END CERTIFICATE-----

You need to copy these (including the begin- and end-certificate lines) and save them to a file. Then fire up pidgin and go to the menu "Tools->Certificate". Now add the a new host and choose the saved file. After that, pidgin should be able to connect to the jabber-server with TSL/SSL again.

First time WEP

2008-06-03T12:13:00.000+02:00

I'm at the University in Zürich at the moment for an international summer school. They provide a wireless network for us and "secured" it with a WEP-Encryption. So this is the first time, I have to use and configure WEP.

8-CURRENT had big changes in the wireless network stack and now uses a virtual "wlanX" device insteed of the normal driver device. So i still do have the iwi-device, which is provided by my wireless network card driver.

iwi0: flags=8843 metric 0 mtu 2290
ether 00:16:6f:81:65:ab
media: IEEE 802.11 Wireless Ethernet autoselect mode 11g
status: associated

But this device isn't used any longer. Insteed a virtual device, named wlan0, is created and configured insteed (see /usr/src/UPDATING on how to do that). The first thing to do is to set this device to up:

ifconfig wlan0 up

If you don't do that, you cannot scan for networks and you cannot configure the device. Next it is necessary to set the session id and the password.

ifconfig wlan0 ssid
ifconfig wlan0 wepkey

Since some devices can have more passwords set, you need to specify which password is used

ifconfig wlan0 deftxkey 1

Then you need to turn on the WEP mode using

ifconfig wlan0 wepmode on

and get an IP adresse

dhclient wlan0

Installing Skype on FreeBSD

2008-05-31T11:09:00.000+02:00

If you want to run Skype, you need a working sound card and a mic. You also need to configure it correctly. The FreeBSD handbook does have enough information on how to do that. Have a look at

www.freebsd.org/doc/en/books/handbook/sound-setup.html

for more information. There is no native implementation of Skype for FreeBSD. But FreeBSD is able to run linux application via an emulation layer. To use this emulation layer, you need to install a linux base system into /compat/linux. For information on how to do and configure the linux binary compability, have a look at the handbook at

http://www.freebsd.org/doc/en/books/handbook/linuxemu.html

As of now, the default linux base system is Fedora core 4 which runs on a 2.4 kernel. But the skype port as of today does require a 2.6 kernel. You therefore need to upgrade you linux_base port to at least linux_base-fc6 (i used linux_base-f8 insteed). /usr/src/UPDATING does have information about how to do that:

20080318:
AFFECTS: users of net/skype net/skype-devel
AUTHOR: beech@FreeBSD.org

For FreeBSD versions 7.0 and above:
It is required with both skype and skype-devel to update to linux_base-fc6.
Please do the following:

1. Make sure there are no running linux applications.
2. Unmount linprocfs (umount /compat/linux/proc)
3. Uninstall your current linux_base port
4. Set appropriate sysctl (sysctl compat.linux.osrelease=2.6.16)
5. Install emulators/linux_base-fc6
6 Remount linprocfs (mount /compat/linux/proc)
7. Add compat.linux.osrelease=2.6.16 to etc/sysctl.conf
8. Add OVERRIDE_LINUX_BASE_PORT=fc6 to /etc/make.conf

Note: These instructions also apply to linux_base-f8, please use the same
osrelease.

For FreeBSD versions 5.x and 6.x:
Please use the legacy version net/skype12

portupgrade -o net/skype12 net/skype

So you need at least FreeBSD 7.0 for running Skype 2.0, all other users have to use Skype 1.2. After upgrading the linux_base, you can install the Skype-Port from /usr/ports/net/skype.

# cd /usr/ports/net/skype
# make install clean

Now run skype and have fun.

Problems:

If you get the message "Problem with Audio Playback" whenever you try to call someone, please make sure that you correctly upgraded your linux_base.

If you cannot hear anything during a phone call or your partner cannot hear you, then check your mixer settings using mixer(1). Make sure the settings "mic, vol and pcm" are at a high level.

Using TMPFS on 8-CURRENT

2008-05-25T16:33:00.001+02:00

There is a new filesystem on FreeBSD 8-CURRENT, which was imported from NetBSD. It's name is tmpfs.

It is marked as highly unstable (and the module will tell you that, every time you mount a tmpfs), but i'm successfully using it for over two weeks without any problems. To mount that file system, you need to load the tmpfs module or you'll have to compile it into your kernel.

kldload tmpfs

You can then mount the filesystem via

mount -t tmpfs tmpfs /mount_point

or you can place the line

tmpfs /mount_point tmpfs rw 0 0

into your /etc/fstab. Have fun

Adding words to vim-spell

2008-05-23T13:46:00.000+02:00

Adding words to your vim dictionary is quite simple. Choose the file you want to save your words (e.g. ~/.vim/dict.add) and add set the spellfile option:

:set spellfile=~/.vim/dict.add

This will create the file and a second file named ~/.vim/dict.add.spl which contains all the words you choose in vim-spell format. To add a new word to the dictionary, just place the cursor on in and press zg. To mark a word as wrong, use zw.

You can manually add words to the spell-file by adding them to the textfile. After you did that, run

:mkspell %

and the .spl-file will be updated. You need to set the spell-file everytime you start vim. If you want to automatically load the spell-file, then place it into your ~/.vimrc.

Ad block lists

2008-05-17T11:02:00.000+02:00

Those of you, who use Firefox probably know about Adblock Plus or some other piece of software that does block ads on websites.

I sometimes use other browsers than firefox and i really miss that feature. I'm quite annoyed about ads on websites and i really don't want to see them. Today i came across this site. It contains a list servers, that do host ads. This list is available in many formats, so that you can block them with different software.

Interrupt make buildworld

2008-05-09T19:15:00.001+02:00

Since I'm on bleeding edge FreeBSD (8-CURRENT), I'm often rebuilding my world quite often. Whenever i interrupted the build processed, I tried to continue it with

# make buildworld

I now found out that this is quite stupid! "make buildworld" cleans the /usr/obj directory and rebuilds everything. This is a good thing, if you updated your sources. But if you only interrupted your build, you can safely go on with the build (at least i think so ;-). You can tell the build process to not clean the object directory by using

# make buildworld NO_CLEAN=YES

Using Xmodmap for umlauts

2008-05-08T10:09:00.002+02:00

I'm a fan of the US keyboard layout, because it's very easy to code with this layout. But i sometimes need to write some German texts and i therefore need umlauts. The solution: "xmodmap". I created the file .xmodmap in my home directory, that contains the following lines:

keycode 113 = Mode_switch
keycode 20 = 0x2d 0x5f ssharp
keycode 34 = 0x5b 0x7b udiaeresis Udiaeresis
keycode 47 = 0x3b 0x3a odiaeresis Odiaeresis
keycode 48 = 0x27 0x22 adiaeresis Adiaeresis
keycode 26 = e E EuroSign

Whenever i run "xmodmap .xmodmap", i'm able to create umlauts using "Alt Gr".

Alt Gr + ; = ö
Alt Gr + ' = ä
Alt Gr + [ = ü
Alt Gr + - = ß
Alt Gr + e = €

Turn off FreeBSD system bell

2008-05-07T15:05:00.002+02:00

FreeBSD has one really annoying "feature": The system bell is activated by default. Whenever you press backspace on an empty command line, there will be this annoying beep. Luckily it can be turned off quite easy. Open a shell and enter

sysctl hw.syscons.bell=0

as root. That's it! If you want to make your changes permanent, you'll have to change your /etc/sysctl.conf. But this is easy, too. Just add the line "hw.syscons.bell=0" to the file and you are fine. You can do this with:

echo 'hw.syscons.bell=0' >> /etc/sysctl.conf

Installing vim spell files on FreeBSD 7.0

2008-05-07T10:33:00.005+02:00

I installed vim71 from the ports on a FreeBSD 7.0 machine and wanted to do spell checking on a German text. But the vim installation did not provide any other language files than the English ones.

I therefore wrote a little script that downloads and installs the needed language files into /usr/local/share/vim/vim71/spell/. You can find this script here if you are interested in it.

You need to run it as root like this:

# ./install-spell-files language

To activate the new language within vim, you need to issue

:setlocal spelllang=language
:set spell

within vim. You can also place these commands into your .vimrc

some quick vim notes

2008-04-07T18:27:00.003+02:00

Make "backspace" behave like in an ordinary editor (e.g. delete empty lines):

set backspace=indent,eol,start

Comments lines with ", + comment_sign"

map ,# :s/^/#/
map ,/ :s/^/\/\//
map ,> :s/^/> /
map ," :s/^/\"/
map ,% :s/^/%/
map ,! :s/^/!/
map ,; :s/^/;/
map ,- :s/^/--/

Delete comment control sequences from lines:

map ,c :s/^\/\/\\|^--\\|^> \\|^[#"%!;]//

Outch!

2007-08-26T19:32:00.001+02:00

Backenfutter

2007-08-22T11:30:00.000+02:00

I tend to get really pissed whenever I have to deal with code that doesn't work, has stupid bugs and/or is bad (or even not) documented. This video cheers me up, whenever I'm in such a bad mood:

Paperclip

2007-08-21T12:08:00.000+02:00

Chris sent me that little gif animation:

He was pretty surprised when I pointed him to Vigor. He told me that he has a new favorite editor after visiting this site ...

Update: Seems like the gif animation doesn't work within a blog post. Click the image to see the full animation.

Vimperator

2007-08-20T10:56:00.001+02:00

First there was a Navigator, then there was an Explorer. Later it was time for a Konqueror. Now it's time for an Imperator, the VIMperator :)

That's the welcome message at vimperator.mozdev.org. Vimpreator is a plugin for firefox, that lets you control your browser like vim.
This plugin is a extension to firefox, if you like vim. You can browse a HTML-Page like you would browse text files in your favorite editor. Have a look at the available commands and try it yourself.

Common VPN Security Flaws

2007-07-24T15:02:00.000+02:00

That's the name of an interesting paper published on the website of NTA Monitor. From the abstract:


    This paper outlines some of the common VPN security ﬂaws that NTA
Monitor have found during the last three years while performing VPN se-
curity tests. The paper concentrates on remote access VPN conﬁgurations
using the IPsec protocol, although some of the ﬁndings are also applicable
to site-to-site VPNs.
    Some of the problems that have been seen, such as the username enu-
meration issue, are new discoveries, while others are known limitations of
the protocols, which are exposed due to poor conﬁguration.
    The paper shows that VPNs are far from the impenetrable systems that
many people believe them to be, and that they can actually be the weak link
in an otherwise secure system.

You can also obtain ikde-scan, an IPsec VPN scanning, fingerprinting and testing tool, from their website.

splash screen on emacs 22

2007-06-29T16:04:00.000+02:00

If you specify files on the emacs command line, you'll notice an annoying feature of the new emacs version 22. The splash/help screen is always been shown. You need to click a mouse button or press a key before you can see the content of your files.

Append

(setq inhibit-splash-screen t)

to your init scripts in order to avoid this "feature".

Skype 1.4 Alpha for Linux

2007-06-07T23:57:00.000+02:00

While browsing some skype related sites, i came across the skype developer site for skype on linux. There's a new version of skype for linux approaching. The release number will be 1.4 and (according to the developers blog), it will be out in about 2 months. According to the developer blog, the new version will be compatible with version 3.2 on windows. That means that linux users can participate on skypecasts like any ordinary windows user!

The devs released a preview alpha version in late april and opened a public bug tracker for the alpha binaries.

I'm going to check that out now ... *download*

Update: Test results: The overall voice quality improved a lot. The user-interface looks better, too (although it isn't fully implemented yet). One is able to see all the participants within a skypecast, but it's not possible to see who is allowed to speak. You also cannot manage a skypecast yet :(

Talent in action!

2007-05-30T23:46:00.000+02:00

Schäuble

2007-05-22T14:46:00.001+02:00

Daylight Exacerbates Warming

2007-05-16T16:45:00.000+02:00

Well ... i should prepare for my next exam on tuesday right now ... but surfing the net is much more fun:

Friendly fire

2007-05-14T21:47:00.000+02:00

Über eine großartige Aktion der deutschen Marine berichtet heute Spiegel Online:

Deutsche Fregatte beschießt sich selbst

Der Schuss ging nach hinten los: Durch ein Geschoss aus der eigenen Bordkanone hat sich die deutsche Fregatte "Lübeck" bei einer Ausbildungsfahrt vor der britischen Küste selbst beschädigt. Verletzt wurde glücklicherweise niemand.

Best sequel ever

2007-04-11T23:52:00.000+02:00

There are only few movies that are worth to be continued. But you'll find _a lot_ (annoying) sequels ... It's therefore hard to find good ones. Here's my top three:

Saw II

Alien II

Terminator II

Forget about Matrix II, Lord of the Ring II or Star Wars II, these three movies are the best sequels ever (or at least the best ones that i know about :D)

If you know another movie that should be on my list, then please let me know.

cpufreq on archlinux

2007-03-26T16:17:00.000+02:00

I don't care about the noise my laptop produces, but when i sit at the university library the cpu fan seems to be very noisy =) The fan starts running from time to time and is very aggressive in its cooling attempts. I hope to get some improvements in this concern with cpu frequency scaling.

My Intel Celeron M (1.40GHz) can run at 175 MHz, 350 MHz, 525 MHz, 700 MHz, 875 MHz, 1.05 GHz, 1.23 GHz and 1.40 GHz. To activate the frequency scaling one needs to load these kernel modules:

p4_clockmod

cpufreq_userspace

cpufreq_ondemand

speedstep_lib

You can load these modules at boot time by adding them onto your MODULES line in your /etc/rc.conf. You're able to set the desired frequency via cpufreq-set afterwards (you may need to install the cpufrequtils package).

The desired frequency for me is 175MHz. In order to get this, i perform "cpufreq -f 175" at the command line (as root). That does slow down all of my applications a lot, but i don't need the laptop extensively when i sit at the libraries.

You might want to load the "ondemand" cpu frequency governor for better performance. It will adopt your cpu speed to your needs. If you use the cpu heavily, ondemand will give you a high cpu speed. But if you do much idling, the cpu will run at low rates. Since 175MHz can be really slow, you can set another minimal frequency for the governor (e.g. 525MHz):

cat 525000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

Konqueror magic

2007-03-20T19:19:00.000+01:00

I just found the following interesting features in konqueror by fluke:

You can control konqueror the same way that you can control vi! Press h for left, j for down, k for up and l for right.

You can open a konsole terminal window with the current konqueror directory as working directory by pressing F4 (don't do Alt+F4 ;))

Did you know them? Neat, isn't it?

Programmer Personality Test

2007-03-06T20:50:00.000+01:00

Moemoe had an interesting entry in his blog today: The Programmer Personality Test. I tried it and got:

Your programmer personality type is:

PHTB

You're a Planner.
You may be slow, but you'll usually find the best solution. If something's worth doing, it's worth doing right.

You like coding at a High level.
The world is made up of objects and components, you should create your programs in the same way.

You work best in a Team.
A good group is better than the sum of it's parts. The only thing better than a genius programmer is a cohesive group of genius programmers.

You are a liBeral programmer.
Programming is a complex task and you should use white space and comments as freely as possible to help simplify the task. We're not writing on paper anymore so we can take up as much room as we need.

Nerd-Test (2)

2007-03-02T00:05:00.000+01:00

I took the nerd test at nerdtests.com last year. Scored 79 back then. Well .. i tried again today and got:

I'm not sure yet, if that score is better than the previous result ...

And the geek tests says:

Testing Arch Linux

2007-02-28T22:18:00.000+01:00

It might not be new to you, but i'm still looking for my favorite linux distribution. Right now a new candidate for the "best linux distribution ever" appeared on my laptop: Archlinux.

The Archlinux people promise to ship

a lightweight and flexible linux distribution that tries to Keep It Simple

And they seem to keep this promise. You can configure the entire system using $favorite_editor and you won't get any extensive problems because of that (ever tried to configure ubuntu w/o their gui-tools?)

The Arch Linux packages are quite new (even the ones in the stable branch) and the upgrade process is steady, like the one found in gentoo. These are important aspects for someone like me, who always likes to be on the bleeding edge :D

And last but not least: Arch Linux ships with a feature, that i immediately fell in love with: Network profiles that can be chosen at boot time!
Just create different profile files in /etc/network-profiles and Arch will present a dialog at boot time, where you can choose the desired profile.
You want to switch the profile at run time? No problem! Just execute "/etc/rc.d/network restart"!

Arch Linux seems to be a serious candidate for the "my favorite linux distribution" award. It seems to bring the best of gentoo and ubuntu together: A clean and easy to maintain configuration system that just works!

Let's see what problems occur during the steady update process ...

Yzis

2007-02-27T22:03:00.000+01:00

Some of my skype contacts asked me to blog in English and i promised to do so ... So here we go:

I've been looking quite a while for an vi-clone that integrates nicely into KDE. I used to use vim for my day-to-day command line editing and needed an editor that can do the same things embedded into KDE applications.
My first guess was to google for "kvim", which brought up some interesting threads about kvim. Most of them where like "where the f*** has kvim gone?"

One of the countless KDE mailing list pointed out Yzis to be the successor of kvim. I browsed their website and came across the history section: Yzis was created by the same guys who wrote kvim.
They dropped the project because it became to difficult to integrate kvim properly into KDE and started an own vi-clone.

Yzis is still work in progress and hasn't had an official release yet, but the current source seems to be very promising. I'm trying to get nyzis (the ncurses interface to yzis) ready for day-to-day use and will then work a little bit on kyzis (the KDE(4) interface of yzis) :-)

Nerds learn about

2007-02-24T00:12:00.000+01:00

Danke an Martin für diesen großartigen Link:

Stoiber

2007-02-18T22:40:00.000+01:00

Für alle die, die es noch nicht kennen:

und

und

Über jeden weiteren Link dieser Sorte würde ich mich natürlich freuen.

Ohne Kommentar

2007-02-15T23:22:00.000+01:00

http://bl0g.wa-junge.de/2007/02/13/no_863/never-call-me-again/

Brief an Frau Dr. Merkel

2007-02-14T20:17:00.000+01:00

Gerade wurde im IRC folgender Link gepostet:

http://grundgesetzkonform.de/

Dieser enthält einen offenen Brief an die Bundeskanzlerin, der sich mit unserem Bundesinnenminister Wolfgang Schäuble befasst.

Daraus würde ich gerne ein Zitat anführen:

Wir haben schwerste Bedenken gegen unseren Innenminister Dr. Schäuble und sehen in ihm eine deutliche Gefahr für unsere Demokratie und unsere Verfassung.

Dazu kann ich nur eins sagen: "So issch's!"

Emacs artist-mode

2007-02-13T21:46:00.000+01:00

Gerade habe ich einen weiteren tollen Emacs-Mode entdeckt: Den artist-mode
Damit kann man sehr schnell Ascii-Bilder zusammenklicken. Links-Klick ergibt nen Punkt. Rechts-Klick löscht was unter dem Cursor ist. Mit der Shift-Taste kann man Emacs dazu bringen -, \, /, |, o und + beim bewegen der Maus zu erzeugen. Das untere Ascii-Bild habe ich in 30 Sekunden zusammengeklickt (was man auch sieht ;))

Viel Spaß beim ausprobieren.

PS: Den Text zu pasten macht ist natürlich nur dann sinnvoll, wenn die Browser das als fixed-fonts anzeigen würden. Deshalb gibt's an der Stelle halt nen Screen-Shot ...

Emacs autocompletion

2007-02-09T13:01:00.000+01:00

Gerade habe ich einen neuen Emacs-Kniff gelernt. Wie der Titel schon sagt, handelt es sich um das autocompletion-Feature von Emacs.
Durch die Tastenkombination "M-/" versucht Emacs das gerade geschriebene Wort zu ergänzen. Dabei werden alle offenen Buffer nach sinnvollen Ergänzungen durchsucht. Ein weiterer Klick auf "M-/" bringt Emacs dazu das nächste Wort aus der Ergänzungsliste zu verwenden.

Das ganze funktioniert in jedem Modus. Man kann damit normale Worte oder auch Funktionen ergänzen. Unabhängig von der Programmiersprache. Bisher habe ich diese Funktion nur mit C++ ausprobiert und muss sagen, dass ich von dem neu entdeckten Feature sehr begeistert bin. Ob die Funktion auch mit anderen Sprachen so gut funktioniert weiß ich (noch) nicht.

Viel Spaß beim ausprobieren.

PS: Diese Tastenkombination macht nur mit dem US-Keyboardlayout wirklich Spaß ;)

C90 oder nicht?

2007-02-07T10:07:00.000+01:00

Gerade bin ich in der FAQ von de.comp.lang.c auf folgenden Codeschnippsel gestoßen:

#include

int main(void)
{
int result = 1 //* */ 2
;
printf("Dies ist %s C-Compiler\n",(result?"kein":"ein"));

return 0;
}

Dieser soll dank der unterschiedlichen Kommentare selbstständig erkennen können, ob er mit einem C90 oder einem C99/C++ Kompilier übersetzt wurde. Wer das mit dem gcc ausprobieren möchte, muss die Option -ansi oder -std=c89 einsetzen um die Meldung "Dies ist kein C-Compilier" zu bekommen.

Spaßz mit Gentoo

2007-02-01T22:00:00.000+01:00

Heute durfte ich mal wieder erfahren, warum unstable unstable heißt ... Manch einer könnte vermuten, dass es unstable heißt, weil es nicht stabil ist. Und (oh wunder!) genau so ist es.

Da ich immer die neueste Software auf meinem Rechner haben muss(sic!), komme ich um ein

ACCEPT_KEYWORDS="~x86"

nicht herrum. Um gewisse Bastelarbeiten kommt man selbstverständlich nicht herrum, wenn man auf bleeding-edge steht ...

Und diese Bastelarbeiten sind auch der Grund für diesen Post. Er soll mich nämlich daran erinnern, dass ich bei Problemen mit ruby-Packeten erst mal einen downgrade von autoconf-2.61 nach autoconf-2.60 machen soll um dann mit dieser Version ruby neuzukompilieren. Dann verschwinden die komischen Endlosschleifen beim installieren der Pakete :D

In diesem Sinne wünsche ich mir (und natürlich allen anderen Bastlern) viel Spaßz beim weiterschrauben.

Eigener Staat

2007-01-17T23:52:00.000+01:00

Diese Geschichte von Spiegel-Online hat schon was:

http://www.spiegel.de/panorama/0,1518,458242,00.html

Richtig geil wird's allerdings erst, wenn man auf Wikipedia nach dem Land sucht. Man findet dazu nämlich sogar einen ziemlich ausführlichen Eintrag.

qt 4.2.2 / qt-copy und FreeBSD

2007-01-11T22:13:00.000+01:00

Gerade habe ich versucht die aktuelle qt4 Version auf FreeBSD zu kompilieren. Dies schlug leider wegen einem kaputten Test auf die libdbus fehl (configure-option -qdbus war aktiviert).
Die Fehlermeldung sah etwa so aus:

dbus auto-detection... ()
g++ -o dbus dbus.o -L/usr/local/lib -L/usr/local/lib -ldbus-1
/usr/local/lib/libdbus-1.so: undefined reference to `pthread_equal'
/usr/local/lib/libdbus-1.so: undefined reference to `pthread_cond_timedwait'
*** Error code 1

Das Problem ist den den Trolls bekannt.

Es handelt sich dabei um ein typisches Problem auf den FreeBSD-Kisten: Die libpthread kann mit -pthread in ein Programm eingelinkt werden. Viele Sourcen sind dafür leider nicht ausgelegt. Im Fall von qt4.2.2/qt-copy kann das Problem gelöst werden, in dem man die Datei config.tests/unix/compile.tests anpasst:

Aus den Zeilen 27 und 28

-L*|-l*)
LIBPATH="$LIBPATH $PARAM"

wird ein

-L*|-l*|-pthread)
LIBPATH="$LIBPATH $PARAM"

und schon tut der Spaß.

Problem erkannt, aber ...

2006-12-01T09:58:00.000+01:00

Gerade beim mergen ist mir ein Codestück aufgefallen, das sich in etwa so liest:


columnDB* cols[MAX_COLS];
int colCount = 0;
...
while(dbRow = mysql_fetch_row(dbResult)) {
      cols[colCount] = getColumnDbByName(dbRow[0]);
      colCount++;
}

if (colCount > MAX_COLS) {
   msg(MSG_ERROR, "Got too much columns!");
}

Schön das der Kollege erkannt hat, dass mehr Einträge vorhanden sein könnten, als in den von ihm allokierten Speicher reinpassen ... Schade das seine Reaktion auf das Problem viel zu spät kommt.

Na ja, ich kann jetzt auf jeden Fall "segmentation_fault--;" sagen.

Rnd()

2006-11-27T21:03:00.000+01:00

An manchen Fragen erkennt man sofort, dass jemand das Prinzip nicht verstanden hat:

hi all,

IntTemp = Int((255 * Rnd()) + 1)

I used above ASP.NET code. Problem is in " Rnd() "
Rnd() value is changing everytime.

What is the alternative for Rnd()? OR How will stop Rnd() value changes at everytime?

Thanks

Quelle: http://www.experts-exchange.com/Web/Q_22031739.html

Bild bewegt

2006-11-16T10:36:00.000+01:00

Jaja, wir alle wissen das die Bild-Zeitung bewegt. Jetzt sorgt sie aber auf ihrer multimedialen Erweiterung dafür, dass sich die Menschen bewegen: http://notes.computernotizen.de/2006/11/15/bildde-verursacht-pornowelle/

I3 (Teil 1)

2006-11-10T00:48:00.000+01:00

Im WS vor zwei Jahren (zumindest glaub ich, dass es vor zwei Jahren war), hab ich die Vorlesung Peer-to-Peer-Systeme gehört. Dort wurde uns von der super tollen und unglaublichen Internet Indirection Infrastructure erzählt:

Attempts to generalize the Internet's point-to-point communication abstraction to provide services like multicast, anycast, and mobility have faced challenging technical problems and deployment barriers. To ease the deployment of such services, we have proposed an overlay-based Internet Indirection Infrastructure (i3) that offers a rendezvous-based communication abstraction. Instead of explicitly sending a packet to a destination, each packet is associated with an identifier; this identifier is then used by the receiver to obtain delivery of the packet. The figure below shows a host R that inserts a trigger (id, R) in the i3 infrastructure to receive all packets packets with identifier id.

Wir sehen also, dass die Welt dadurch ein Stückchen besser wird ... und ja: Der Dozent ist/war daran beteiligt ;)

I3 implementiert ein Peer-2-Peer-System auf der Grundlage eines Chord-Ringes. Dadurch soll eine Nachricht nicht mehr als O(log(N)) Server passieren, bevor sie am Ziel angelangt. Durch weitere Optimierungen (v.a. Caching und location-aware Triggern) soll das ganze sogar noch schneller gehen.

Nachdem ich damals in der Vorlesung ziemlich viel über dieses super-duper-tolle Overlaysystem gehört hatte, wollte ich das System nun mal in Aktion sehen. Also hab ich mir vor ein paar Stunden den Code runtergeladen und kompiliert.
Bzw. ich habe es versucht. Der Code kompilierte bei mir nämlich nicht vollständig. Die Entwickler scheinen sich des Problems aber bewußt zu sein und haben einen configure-Switch zur Verfügung gestellt, mit dem man den problematischen Codeteil deaktivieren kann.

Nachdem ich diese Probleme hinter mich gebracht hatte und die Doxygen-Doku ebenfalls fertig gebaut war, machte ich mich ans Werk: Das erste Testprogramm wollte geschrieben werden.

Der erste positive Eindruck kam mit der I3-Clientapi. Diese ist nämlich sehr klein und damit einfach zu verwenden (allerdings handelt es sich dabei um eine C-Api, welche per Definition häßlich ist!). Es ist noch nicht einmal viel Doku notwendig um sich in die API einzuarbeiten. Die Doxygen-Methodendokumentation und die kleinen Beispielprogramme reichen dazu vollkommen aus.

Gerade habe ich meine erste I3-Anwendung fertig gestellt. Sie schickt den String (ja, genau den!) in das I3-Netz und liest ihn wieder aus. Jetzt bin ich auf der Suche nach einer richtigen Anwendung die ich implementieren kann ... Habt ihr irgend welche Ideen?

Jahreshauptübung 2006

2006-11-06T12:44:00.000+01:00

Wie jedes Jahr fand auch 2006 am ersten Novemberwochenende unsere Jahreshauptübung statt. Traditionell probten dabei die FFW Bodelshausen zusammen mit dem DRK Ortsverein Bodelshausen den Ernstfall.

Dieses Jahr durften wir im und um das neue Altenpflegeheim werkeln. Die Feuerwehr nutzte diese Gelegenheit auch zur Ersterprobung der Brandmeldeanlage.

Bilder der Übung werde ich demnächst online stellen (sobald ich rausgefunden habe, wer welche gemacht hat :D). Auch auf userer DRK-Homepage werden sie (hoffentlich) bald zu sehen sein. Zumindest befinden sich da die Bilder der letzten Jahre.

The System Administrator's Song

2006-10-29T13:11:00.000+01:00

Viel Spaß damit:

Dazu nochmal Wes Borg mit seinem "Internet Helpdesk":

Die kalte Jahreszeit ...

2006-10-27T22:37:00.000+02:00

Woran merkt man, dass der Sommer vorbei ist? Klar: Die Erkältungszeit beginnt wieder. Und mich hat's jetzt schon erwischt.

Pünktlich zum Wochenende! Wann denn auch sonst?

Hoffentlich ist das bis Sonntag abend wieder vorbei. Denn da steigt die Geburtstagsparty von Edga. Der Gute ist am Donnerstag vierundzwanig geworden und soll sich an dieser Stelle nochmal mit einem "alles gute zum Geburtstag"-Gruss bedacht fühlen.

Big Brother auch im Nachbarland

2006-10-26T17:41:00.000+02:00

Auch unsere Nachbarn in Österreich vergeben "Big Brother Awards". Kuhlerweise gibt es hier auch einen "dümmste Begründung"-Award:

Der erstmals verliehene Preis "Pro-Stupiditate" geht an Brigitte Ederer, Chefin von Siemens Österreich, für die dümmste Ausrede.
Im neuen Biometrie-Kompetenzzentrum von Siemens wird unter Ederers Regie der Einsatz dieser Technologien aus dem Hochsicherheitstrakt bis hinab in die einfachsten Abläufe des Lebensalltags propagiert: Von Biometrie-Eintrittskontrollen bis zum Getränkeautomaten, der sich nur nach Abgabe eines Fingerabdrucks bedienen lässt.
Eine Verantwortung für die möglichen gesellschaftlichen Folgen dafür will Ederer nicht übernehmen, sondern schiebt sie auf eine Gesellschaft ab, die solcherart von Siemens über diese Technologie "informiert" wird.

Na dann Mahlzeit ...

Big Brother Award

2006-10-25T16:27:00.000+02:00

Am 20. Oktober war es mal wieder soweit: Die Big Brother Awards 2006 wurden vergeben. Wieder wurden die gröbsten Datenschutzverletzungen der Republik mit einem Negativpreis geehrt. Als ich heute die Gewinnerbeiträge überflog wurde mir klar, wie normal die ganze Datensammlerei und der ungehemmte Datenaustausch in der heutigen Zeit ist. Und mit jeder neuen Runde werden mehr Daten gesammelt. Und die Gründe dafür werden immer fadenscheiniger ...
Gleichzeitig nimmt der Wiederstand gegen die (willkürliche) Datensammlerei immer weiter ab. Wenn man sich überlegt, dass die Menschen vor 20 Jahren gegen die Einführung einer Volkszählung auf die Straßen gegangen sind, wirkt die heutige Teilnahmslosigkeit erst recht erschreckend ...

Langeweile

2006-10-08T13:46:00.000+02:00

Moin,

mich hat gestern mal wieder die Langeweile voll im Griff gehabt. Und was passiert in diesen Momenten?

Richtig! Ich hab mir ein neues Betriebssystem installiert. Diesesmal hatte ich mal wieder die FreeBSD-CDs in den Haenden ... und jetzt laeuft ein schickes BSD auf meinem Laptop ...

Genauer gesagt: Es kompiliert freudig an der neuesten KDE-Version vor sich hin ... und das wird wohl noch ne Weile dauern :D

Das gute daran ist, dass mir das das Zeit zum lernen laesst *g* Die naechste Dipl-Pruefung steht bald an :)

MonAM

2006-10-04T12:03:00.000+02:00

Letzte Woche (Donnerstag und Freitag) fand der Workshop MonAM 2006 - Monitoring, Attack Detection and Mitigation - in Tübingen statt. Während des Workshops gab es eine Reihe interessanter (und auch eine Reihe weniger interessanter) Vorträge aus den Bereichen der Netzwerkverkehrsüberwachnung und der Angriffserkennung.

Gleichzeitig stellte der Workshop das Ende des DIADEM Firewall-Projektes dar. Nach einer erfolgreichen Abschluß-Demo wurde das Projekt am Freitag nach dreijähriger Laufzeit beendet (nun laufen nur noch organisatorische Dinge wie Abschlußpräsentation in Brüssel, Veröffentlichung der Ergebnisse auf einer Konferenz, etc.)
Ich selbst habe als Studienarbeiter und HiWi an dem Projekt mitgearbeitet. In dieser Zeit habe ich an einem Netzwerkmonitor und einem Framework zur Verkehrsdatenanalyse gewerkelt. Auch bei der Erstellung einiger Module zur Angriffserkennung und dem Austausch von Alarm-Nachrichten durfte ich mithelfen.

Der Workshop hat sich auch Abseits der Vortragsreihe gelohnt. Es war eine gute Möglichkeit sich mit Leuten, die auf dem selben Gebiet arbeiten, zu unterhalten. Dabei setzte sich in mir die Idee fest, dass ich meine Diplomarbeit außerhalb von Tübingen machen könnte. Vor allem NEC-Europe in Heidelberg und Fraunhofer FOKUS in Berlin scheinen vielversprechende Kandidaten für eine Diplomarbeit werden zu können.

Softwaretechnik && Co

2006-09-27T11:16:00.000+02:00

Heute konnte ich einen weiteren Meilenstein auf dem Weg zum Dipl-Inf erreichen: Die praktische Informatik ist prüfungstechnisch abgehakt. Am Ende steht die 1, nachdem ich heute in der SWT+CP+PFI-Kombiprüfung eine 1,0 abgreifen konnte :)

Ganz großes Kino

2006-09-26T22:44:00.001+02:00

Gerade kam ich in den Genuß von ganz großem Kino:

http://users.skynet.be/osmo/uNF/blas.swf/

Und wie bei allen großen Klassikern gilt auch hier: Der wird immer besser, je öfter man ihn sieht.

Studienarbeit, (fast) das letzte Kapitel

2006-09-21T22:31:00.000+02:00

Heute um 11:35:50 Uhr war es soweit: Ich bekam endlich das lang erwartete "die Ausarbeitung ist gut so" von Gerhard. Nur ausdrucken, ringbingen, unterschreiben und abgeben musste ich sie noch. Glücklicherweise ist alles dafür Notwendige am Lehrstuhl vorhanden.
Also bin ich heute kurz auf die Morgenstelle gefahren, habe 4 Exemplare gebastelt (drei zur Abgabe, eins für mich) und damit das Kapitel Studienarbeit (fast) abgeschloßen.

Jetzt muss ich nur noch irgendwann den Schein abholen ... Und genau da liegt das "fast" (also das Problem). Wer mich kennt weiß, dass es noch eine Weile dauern kann, bis ich den Schein wirklich in den Händen halte

...

Und nein: meine Rechtscheine habe ich immer noch nicht ...