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10 Awesome Features of Krunner in KDE 4

Tavis J. Hampton — Mon, 29 Jun 2009 12:21:00 +0000

Many KDE 3 users depended on Krun, a simple yet effective application used to execute commands. Executed simply by pressing “Alt-F2″, it was much easier to start applications using it, rather than navigating through a launch menu or opening a terminal window. The only catch with Krun was that you had to know the exact name of the command you intended to launch. With the advent of KDE 4, that has all changed.

Krunner operates independently of the Plasma desktop system as a standalone application. It includes a ton of features that make it useful beyond simple command launching. It has retained many of the features present in KDE 3 and greatly expanded them. We would fail to do it justice if we did not give it a top ten list.

10. Calculator

Do you need to figure out how much money you have left for groceries after subscribing to three MMORPGs? Just press “Alt-F2″ or right click on the desktop and press “run command”. To use Krunner as a calculator, type the = sign and then enter the equation. For example, type “=890*12″, and it will output a calculator icon and the answer: “10680″. Simply select the answer to calculate the next equation with it. KDE 3 had a similar calculating feature that automatically opened Google’s calculator. With this you can calculate multiple times without leaving the Krunner window.

9. Spellchecker

If you are anything like me, you are obsessed with spelling things correctly and yet could not spell to save your life. If you happen to be typing a blog post in OpenOffice.org or using Firefox’s spellcheck feature, you will be safe. But if you are in the middle of one of those MMORPGs and need to spell “elemental” correctly, hop into windowed mode and press “Alt-F2″. Then type “spell:” followed by your best attempt at spelling the word you need. Krunner will offer suggestions.

8. Unit converter

Are you planning to visit any country outside of the U.S. and cannot understand why people “don’t speak American”? KDE will rescue you again. Open Krunner and enter a number and any unit you can imagine. By default, it will convert that unit to meters. Add “in” or “as” followed by another unit, and it will immediately output the conversion. For example, type “5 miles in cm” and it will output: “804672 centimeters”.

7. Contact finder

Whenever you need to shoot off a quick email, just type in the name of a person in your address book (You must use Kaddressbook for this work). Krunner will pull up any names close to what you type and display: “Mail to so-and-so”.

6. Website launcher

Krunner can launch any website you type in your default browser. It will also use konqueror shortcuts. For example, to search Google Images, enter: “images: pandas”. It will display its function before you press enter: “Search Google Image Search for pandas”. It can also launch bookmarks and browser history.

5. Location launch

Are you tired of navigating through file folders? Just type in the folder you want to reach in Krunner. If you want to open your Music folder, just type “Music”. It is really that simple.

4. Desktop search

You know you typed a paper two years ago on tectonic plate shifting, but you just cannot find it. If you are using Strigi, KDE’s desktop search system, Krunner can find it. Type in any search terms you want and let the desktop searching do the rest.

3. Task manager

A slimmed down version of ksysguard, KDE’s task manager is available as a component within Krunner. Users can access it by clicking on the second icon from the left in the Krunner window or by pressing Ctrl-Esc anywhere within KDE. It is quick and easy, allowing you to monitor CPU and Memory usage. You can also kill applications at will. Use with care.

2. Application search

Suppose you want to launch a card game but cannot remember the name. Just type in “card” into Krunner, and your card game applications will appear. You can also begin typing the name of an application, and Krunner will display all the applications that start with those letters while you are typing.

1. Command launcher

Even with all of the new features, nothing beats the original. Krunner is still a command launcher and still keeps a history of commands you have launched, which you can display either by beginning to retype them or opening the drop-down menu. Therefore, you only have to type “kdesudo kate /etc/X11/xorg.conf” once, and Krunner will remember it the next 20 times you want to tweak your X server.

Perhaps the greatest thing about Krunner is that it is extensible. Many of the plugins mentioned above were authored by users who were not on the original Krunner development team. Anyone can write a plugin, making the possibilities endless. Any plugins you do not like can be disabled, so KDE 3 purists can return it to command-launching-only status anytime they like. That is also useful on slower machines. With each release of KDE, however, Krunner will be even faster, with more awesome features to add the list.

*Note: These features are presented as they currently appear in KDE 4.3, scheduled to be released at the end of July 2009.

10 Awesome Features of Krunner in KDE 4 originally published on Make Tech Easier (RSS)

Things You Need To Know To Become An Apt Guru

Joshua Price — Tue, 24 Feb 2009 12:53:42 +0000

Quite possibly the most distinguishing feature of Debian-based Linux distributions (such as Ubuntu, Mepis, Knoppix, etc) is their package system – APT. Also known as the Advanced Package Tool, APT was first introduced in Debian 2.1 in 1999. APT is not so much a specific program as it is a collection of separate, related packages.

With APT, Linux gained the ability to install and manage software packages in a much simpler and more efficient way than was previously possible. Before its introduction, most software had to be installed either by manually compiling the source code, or using individual packages with no automatic dependency handling (such as RPM files). This could mean hours of “dependency hell” even to install a fairly trivial program.

In this article, we are going to highlight some of APT’s best features, and share a few of the lesser known features of APT and its cousin dpkg. Believe it or not, APT can even be used to solve Sodoku puzzles!

dpkg

The base of Debian’s package system is dpkg. It performs all the low level functions of software installation. If you were so inclined, you could use dpkg alone to manage your software. It can install, remove, and provide information on your system’s software collection. Here are some of my favorite features.

Basic installation of local file

Some software authors create Debian packages of their programs, but do not provide a repository for APT to fetch from. In this case they just provide a downloadable .deb file. This is very similar to RPM packages, or even Windows .msi files. It contains all the files and configuration information necessary to install the program. To install a program from a .deb file, you simply need

dpkg -i MyNewProgram.deb

The -i, as you may guess, tells dpkg to install this piece of software.

Listing a package’s contents

You may find yourself, after installing a program, unable to figure out how to run that program. Sometimes, you need to know where to find the config files for your new game. Dpkg provides an easy way to list all the files that belong to a particular package.

dpkg -L MyNewProgram

Note that case matters. -L and -l are entirely different options.

Often, a package has so many files it can be difficult to sift through the list to find the one(s) you’re looking for. If that’s the case, we can use grep to filter the results. The following command does the same as above, but only shows results that have “bin” in the path, such as /usr/bin.

dpkg -L MyNewProgram | grep bin

I won’t even begin to go into the awesome power that is grep, but in its simplest form it can be used, like above, to quickly and easily filter a program’s output.

Finding the owner of a file

Occasionally, you find yourself in a situation that’s the reverse of the section above. You have a file, but you don’t know what package it belongs to. Once again, dpkg has you covered.

dpkg -S mysteryfile.cfg

This will tell you which package created/owns that file.

Listing what you’ve got installed

Let’s say you’re about to reinstall your system, and you want to know exactly what you’ve already got installed. You could open up an app like Synaptic and set a filter to show everything marked as “installed”, or you could do it quickly and easily from the command line with dpkg.

dpkg -l

dpkg --get-selections

That will give you one big long list of everything you’ve got installed. Advanced users could use these commands to create a text file with all their packages listed, which could be fed into APT later to reinstall everything at once!

Reconfiguring a package

When a .deb package is installed, it goes through a few stages. One of those is the configuration stage, where developers can put a series of actions that take place once all the files have been installed to a proper location. This includes things like start/stopping services, or creating logs, or other such things. Sometimes you need to repeat those steps, without going through the whole reinstallation process. For that, you use:

dpkg-reconfigure (packagename)

This will redo all the post-install steps needed for that package without forcing you to reinstall. Believe me, this one comes in handy.

Aptitude/Apt-get

There’s some debate and confusion regarding these two tools. Many Linux users have a hard time telling when/why to use one over the other, as they do roughly the same thing.

Short answer: use Aptitude.

Long answer: Both can be used to manage all software installations removals, and both will do a good job. The Debian team officially recommends using Aptitude. It’s not that it’s a LOT better than apt-get, but that it’s a little better, in lots of ways. You can use either one and it will meet your package management needs, but don’t mix and match on the same system. Pick one and stick with it.

Finding the right package

I often find myself in need of software to do a certain thing, but I don’t know the name of any programs to do it. For example, I may need a FLAC player, but don’t know offhand what player will work…

Aptitude:

aptitude search flac

Classic APT:

apt-cache search flac

You’ll get a list of available packages that have “flac” in the name or description.

Preventing a package from updating

On some occasions, I have a version of a package that I want to keep even though there may be upgrades. When it comes to my kernel, for example, I prefer to update manually.

Aptitude:

aptitude hold (packagename)

dpkg:

echo "(packagename) hold" | dpkg --set-selections

Upgrading

Both Aptitude and classic APT provide two methods of upgrading your system: upgrade and dist-upgrade. This is another thing that causes some confusion. An upgrade is an upgrade, right? Well not exactly.

A regular upgrade will read your list of packages, check online for newer versions, and install them as needed. It will NOT, however, perform any upgrades that would require new packages installed, or existing ones removed. This is what dist-upgrade is for. It will get every newer version it finds, even if it involves installing something new (such as a dependency) or removing an existing package (if it’s obsolete or is no longer needed).

Aptitude:

aptitude safe-upgrade
aptitude full-upgrade

Classic APT:

apt-get upgrade
apt-get dist-upgrade

Learn about a package

Finally, some times you just need to know a little about a package. What version is it? Who maintains it? Is it already installed? All these things and more you can find with:

Aptitude:

aptitude show (packagename)

APT:

apt-cache showpkg (packagename)

All of the programs mentioned here are capable of far more than I’ve shown. The tips here should go a long way in helping you use this amazing package system to its full potential.

Also, for those with the patience to read all the way to the end,

apt-get moo

Things You Need To Know To Become An Apt Guru originally published on Make Tech Easier (RSS)