I used to use Lightning for my google calendar in versions before .7…

When .7 came out, it caused Thunderbird to rocket memory usage above 80% which brought my computer to a screeching halt.  I figured I’d not use it until next version (and submitted a bug report as well).

Today I downloaded .8 in hopes it would work better.  It doesn’t.  Memory usage still skyrockets when attempting use the google calendar (provider addon) and the remember mismatched domains add on with it (otherwise you’re unable to connect or get a popup every time you view).

Is it one of these plugins causing it?  Is it Lightning?  I’m leaning toward the latter…even when uninstalling the extensions, I still get memory usage skyrocketing.  Either way, syncing your google calendar with Lightning isn’t a very smooth thing to do if it causes your Linux desktop to screech to a halt.

I guess there is always evolution with built in google calendar support.  Anyone else getting these problems?

At work, we use Zimbra for emailing.  I use Thunderbird with IMAP as my desktop client.  I’ve also seen that as of Zimbra 5.0 RC2, they will have the ability to sync with Lightning.  Good news!  Now if Lightning would stop leaking!

Thunderbird and Lightning .8 originally appeared on Yet Another Linux Blog on April 7, 2008.

Let’s start off by seeing if the cron daemon is even running on your system. Open up a Konsole or Shell and type the following:

ps aux | grep crond

If there is output similar to that in the screenshot, we’re in business because the cron daemon is running. If not, restart cron by typing: ./usr/sbin/crond (may vary by your distro…if you need help, let me know in comments section).

I use PCLinuxOS for my Linux desktop. You can find Kcron by navigating to Kmenu >> Configuration >> Other and selecting it.

Kcron will open and you’ll see the default menu. You should see two categories in the main area: “Tasks” and “Variables”

Variables identifies items you can set to help with your task scheduling. For instance, say you want a custom variable to stand for one users’ desktop…so you’d set the PATH variable to their /desktop. Now remember, when you set this variable, Kcron will use in in lieu of the normal path. There are also other variables you can set. There is extended help on variables in the Kcron handbook. For now though, let’s look at the other item on our list…and, subsequently, the meat and potatoes of what Kcron does. Tasks.

With Tasks, you setup the command you want to execute. This can be something simple like mailing you out a synopsis of logs or even nmap penetration scans. It’s up to you what you want to do with it. We’ll start with something extemely simple to show how Kcron works.

Highlight “Tasks” then select the Edit menu and choose “New”

This should bring up a new task menu. Glancing over this menu, you can see that things are pretty self explanatory. You have dates and times, options for repeating weekly, monthly, or daily. Basically, it’s spelled out for you. This is much easier than the old way of doing crontabs where one had to enter into the crontab file and place asterisk after asterisk and remember what each one of those asterisks meant and try to keep one’s place with all the asterisks to remember which placeholder to flag to enable the cron. Now, it’s as easy as point and click.

For training purposes, we’ll setup a task that should already be setup by default in most distributions…we’ll schedule an index update for file location purposes. Just like windows uses indexing service, Linux has a built in ‘indexer’ (term is used loosely here because it is really a database of your filesystem) that we can populate and update…which you’ll want to do, especially if you install many updates. As stated earlier, this task should already be scheduled in most distributions by default. Let’s practice though by setting it up to run. Looking at the window we opened in the previous paragraph, enter in the comments “My First Linux Task – Updatedb”. Next, for the command, enter “/usr/sbin/updatedb”. Now choose when you want to run it. I chose every Wednesday of each and every month at 9:30 AM. After I set this, I choose “Ok”. Now we must save the task.

Go to File >> Save and now you’re in business. Never forget to save AFTER you’ve altered the task, otherwise your changes will go right out the window.

You can get more creative and add your own custom paths or mail addresses by using variables. As you can see in the screenshot above, I’ve input my mail address in case I want my cron output mailed to me.

Remember, as long as you know the command that you want to do, you just place it in the blank, schedule it, make sure the enable box is checked, and save. For instance, say you want to backup your files for linux to your windows share. You could use the following command to back things up into a handy tar archive:

cd /home/devnet;tar -cvf – * | tar -C /mnt/windows/share/backup -xv

The only limitation is knowledge. If ever you are in doubt of what a certain function entails, open up the Kcron handbook. It might not answer your question but you can get pointed in the right direction. Another good resource would be the developers. If there is one thing I know about KDE its that the developers are always willing answer a rogue question about the functionality of their application.

You can find both the programmers/developers of Kcron and the Kcron handbook under the help menu. Please remember that developers can answer questions about the application but are not there to come up with custom commands for you to use in Kcron…you’ll have to do that legwork yourself! Hopefully, this will get you started scheduling your own backups and tasks.

Schedule Tasks in Linux with Ease – Kcron originally appeared on Yet Another Linux Blog on December 15, 2005.

In most KDE default KDE desktops on the major distros, you find this little icon:

That icon is Klipper, your clipboard tool. A clipboard is just what it sounds like…a place where you can clip text to be used at a later date. I wanted to take a look at where Klipper came from…so I went into the ‘about Klipper’ menu and emailed a couple of developers. A few actually responded quelling the myth that developers are unreachable by the general public. Carsten Pfeiffer, a previous developer, responded about the history of Klipper:

“It was started long time ago by Andrew Stanley-Jones, for storing a history of clipboard entries. I took over maintainership and added those annoying popups, that appeared, for example when you selected a URL in a terminal or somewhere else. The popup allowed you to do something with the URL, like opening it in Konqueror or Mozilla.

More generally speaking, the feature allowed you to configure custom “actions” to execute when something specific, described with a regular expression was put into the clipboard (see klipper’s Preferences dialog).

Later, I attempted to make klipper hide X11′s IMNSHO broken concept of “Selection” and “Clipboard”, but I didn’t really accomplish that.

Later, Lubos Lunak worked hard on fixing Qt’s clipboard implementation and making klipper play well with it and now I’m very happy that Esben is taking care of it.”

I contacted Esben in an attempt to get some inside information about where Klipper might go in the future (integration into KDE-core perhaps? or other such directions). He was able to provide a few possible directions Klipper may go:

“My vision of Klipper is mostly as a clipboard history application… the actions I merely maintain for those that uses them. Thus the features I have implemented so far has centered on the history: Expanding the history (really making the history scalable), support for images (this was sort of a test, I want to support abitrary mime types in history) and search-as-you type support.”

Now that we know where Klipper came from and where it might be going…let’s take a look at where Klipper can go by making it work for you. By clicking your mouse on Klipper or pressing CNTRL-ALT-V, you can access the menu which shows the text currently stored. When this menu pops open, you can search through it simply by typing your query. Klipper hunts the text down that you’re typing. Easy enough to find text…but where we are concerned with for this article is ‘configure klipper’,which is where you can access the menu where customization is king. Let’s see what we can do. Start by opening up the ‘Configure Klipper’ menu.

You’re greeted by a three-tabbed layout that seems easy enough to navigate. Tab 1 is “General” and is where all of your general settings are stored (go figure) such as pop-ups for Klipper and Clipboard size. Tab 2 is “Actions” and is where all of the application actions are stored (we’ll explain these later). Tab 3 is “Shortcuts” and has to deal with Clipboard shortcuts while you are in various applications. We’ll cover shortcuts later as well. For now, let’s take things one step at a time and access Tab 1. If it isn’t selected, select it now by left-clicking your mouse on the tab labeled “General.” You should see the image displayed at the beginning of this paragraph.

The General Tab

The tab marked general contains your most commonly used settings. Klipper allows cut and past of text with Control X and Control V respectively…just like the other operating system does. However, unlike that other operating system, Klipper has two buffers for storing text. One buffer is the “selection” buffer. This buffer allows Klipper to store text when you use your mouse to highlight it. You wouldn’t even need to hit Control C to copy it or Control X to cut it…it would already be present in the “selection” buffer. Now, this isn’t always right for everyone so you can choose to Synchronize the “selection” buffer with the “clipboard” buffer…that is, the other buffer that Klipper saves things to. This buffer can be thought of as the normal clipboard buffer where text is cut and pasted from and to. The settings that control both of these buffers is located in the middle of the “general” tab under “Clipboard/Selection Behavior.” Selecting “Separate clipboard and selection” will cause your clipboard to be completely separate from your selection buffer. Selecting “Synchronize contents…” will synchronize things so that you can highlight text to copy it.

Another often forgotten function of this “selection” buffer, is the abiltiy to use the middle mouse button to paste. Of course, this is only if your middle mouse button works in Linux…and if it doesn’t, please visit the forum and we’ll get you up and running.

Cycling through the settings, we can see as the first setting “Pop-up menu at mouse cursor.” Toggling this on or off will allow the Klipper pop-up menus to happen either in your KDE Panel or at your mouse position. Next up is “save on exit.” This setting is used to access text that you saved in a previous KDE session in Klipper. The next setting is “Remove whitespace.” I love this setting because it removes extra spaces from the text you select/cut/paste. This is handy for cutting and pasting urls and downloads. The “Replay actions” setting will cause the actions for the text that is present in Klipper to display in a pop-up. We go into further detail on this later.

“Prevent and empty clipboard” does exactly what it sounds like it does so we won’t explain that one. Moving further down, “Ignore Selection” means that when you highlight text, Klipper won’t save it in its selection buffer (which we discussed earlier). So really, “Ignore Selection” is a switch to turn off your selection buffer. The two settings after this were discussed in the previous paragraph so we’ll skip them now. The timeout action for pop-ups sets the time that pop-ups will remain visible to you. The last setting is very simply a way to set how many clipboard entries/items are stored in Klipper.

Actions Tab

If you dabble in programming, the actions tab is for you. Actions are based on the Qt 4.0 regexp class which provides a way to dynamically use text. It is important to note that Klipper does not support the wildcard options in the class noted above. So what can this action tab do? Well, you can setup actions to take place on the text in the clipboard. For instance, in the picture at the beginning of this paragraph, you can see the setting “^V.+\.jpg$”. This setting contains one action beneath it…which is “Kview %s”. The “%s” is an alias that stands for the most recent text selection you have on your clipboard. So…if we were to select text that ended in somename.jpg, Klipper would launch Kview to view this picture since the actions denote that it should. You can add other applications in here if you know what name or expression they use to execute. For more advanced use of this function, see the class link above or try the Klipper Handbook Actions Entry.

One good action I came up with was adding Firefox to my URL action in Klipper. This way, when I selected a URL, the pop-up window asked me if I’d like to open it in Firefox. Of course, I chose yes. This is a very simple example…I hope other people have more they might be able to provide to supplement this article with.

The actions menu can really be a powerful area of customization. However, having not used Klipper as much as I should be and only really getting into using it for the last few weeks…I’m not too experienced in tapping into these settings. If anyone has any suggestions as to actions that work for them or suggestions as to what actions and expressions in this menu might provide a better KDE experience, please comment below.

Shortcuts Tab

The shortcuts tab allows you to change the Keyboard shortcuts that are used to access Klipper. Switch them to whatever shortcut you want. Don’t like Control V for paste? Change it! You can even assign an action a shortcut key combination. Klipper leaves it up to you to decide how you want things…it doesn’t decide for you. To change a shortcut, select “Custom” and make your changes. To return to the normal setting, choose “Default.” You can also blank out your setting by choosing “None”.

As you can see, Klipper makes life much easier in Linux that it ever could be without it. The meat and potatoes of Klipper is the action menu and I wish I had more to give everyone to show them how powerful Klipper could be. I did do some poking around on the net to see if I could find a listing of actions or even a few handy ones but I came up pretty much empty. It seems no one has collected Klipper actions. So, here is as good as any place to collect actions right? If you have an action that you find handy, please post it in the comments below. If it checks out and works great, I’ll post it in this article and give you reference for it. Thanks for reading!

Make Klipper Work FOR you originally appeared on Yet Another Linux Blog on November 17, 2005.