Linux

So I tried updating one of my boxen running the Lucid Kubuntu LTS to the new Precise Pangolin beta. During the upgrade, I received an error message stating that adobe-flashplugin could not be upgraded. I ignored it and continued with the upgrade and all went swimmingly. Once the upgrade was completed and I had rebooted, when I tried to run an apt-get update, I ran into an error with respect to the adobe-flashplugin package. When I tried to remove it, it did not work. As a stop-gap measure, I removed a number of packages that depended on it including Firefox and sun-java6.

If you've been working with Linux terminals for a while, you've invariably found that viewing a binary file tends to output a lot of hieroglyphic nonsense (when all you want to do is check its header) and for some petty collateral damage, rapes your screen by changing your command prompt and window title to more of the same gibberish. While a lot of people (*raises hand*) simply accept such rowdy behaviour as one of the vagaries of life and simple open a new terminal window or similar, this - as I found out a few minutes ago - can be fixed.

On an Ubuntu box, I tried using the locate command to find information about a package and ran into the following error:

Today, I made quite an impression on my furniture thanks to incessant contact between it and my illustrious head. This, as usual, was due to my looking for a clean regex to solve my issue while working with text files in Vim. My task was, I initially believed, quite simple: delete all the lines that are sandwiched between two types/patterns of lines. In this case, the top slice of the sandwich consisted of a line which was entirely a number and the bottom slice was a line entirely populated with underscores.

One of my laptops which is running on Kubuntu Lucid decided to stop connecting to my network today. I found that the KDE network-manager applet (or is it a plasmoid? :S) had decided to disable itself. Clicking it stated so with no option to re-enable it (nice UI, boys). Getting to the commandline and starting the network-manager service did not help. I also found that accessing the System settings networking configuration gave me corrupt XML file errors.

I ran into the following error when I added a new repository to my kubuntu box and ran apt-get update:
E: Dynamic MMap ran out of room. Please increase the size of APT::Cache-Limit. Current value: 123123. (man 5 apt.conf)

To fix this, navigate to /etc/apt/apt.conf.d and edit the file related to debconf which in my case was 70debconf. Add the following line to the bottom of this file and save it:
APT::Cache-Limit "200000000";

If you run into the following error message when attempting an iptables-restore < my.rules:
iptables-restore v1.4.8: no command specified
then the problem is that you have very likely just copied and pasted stuff into my.rules which has led to some dodgy line-breaks terminating blank lines in the file.

On a server I am working on right now, I installed a PHP application and attempted to run it. However, I ran into a "500 Internal Server Error". Upon further investigation by checking the logs, I found the following errors in the Apache error log:

I work extensively on a Windows desktop. However, I do SSH into Linux servers often and I do so using PuTTY, a free and open source client. Everything works peachy. However, I recently had occasion to work extensively with some Unicode source data and I found that there were times when I thought that there were encoding issues with the data as they were not being displayed correctly on my screen.

It is often important, especially when dealing with databases and such, that files are stored in the correct character set. Failure to do so can result in illegible displays or even data corruption. Checking the character set of a file in Linux can be accomplished using the file command:

Jubal@Stranger:$ file migrate1.csv
migrate1.csv: Little-endian UTF-16 Unicode English text, with CRLF, LF line terminators
Jubal@Stranger:$ file migrate2.csv