Hello readers! This post is a list of soft phones available for Linux. It is not an all inclusive list, more of a list of those I’ve installed or tested. These are just a handful of them, there are probable way more available that I’m not aware of. Some of these are cross platform and are listed if they are available in Ubuntu and Fedora’s repositories as of the time of this writing. Use the comments to let me know of any good ones or which ones you’ve used or recommend!
Although not necessarily classified as shell scripting its self cron’s are very useful to any Linux administrators arsenal. The ability to run tasks at a specific interval is a great way to schedule things to run later or when the system load is lower. Many applications use crontab to schedule tasks so its hard to say what yours will look like.
will list all of the cron jobs scheduled for the currently logged in user mine has an entry for kpodder
# (Cron version V5.0 -- $Id: crontab.c,v 1.12 2004/01/23 18:56:42 vixie Exp $) #KPodder entries 0 0 * * * kpodder.sh -c "/home/owen/.kde/share/apps/kpodder/" -s "global.casts" -o "/home/owen/podcasts" -d 0 #KPodder End
The first five fields are to tell the task when to run. They are in the following order: minute, hour, day, month, day of the week. Asterisks are used to say any valid value and a forward slash can be used to make intervals such as five minutes, hours, days or months (*/5). A comma can be used for or values, so if used as 2,4,6 the cron would run at 2, 4 or 6 o’clock. Dashes are used for time spans, If you have an 8-5 work day you can use 8-17 if in the hours field.
Next, the sixth field is the actual program to run. It will look in the $PATH for the user, but for safety’s sake, I try to use the full path if possible. In my example of the kpodder script there are many arguments. I only really use simple crons and the number of arguments here seems rather excessive.
To edit the crontab do crontab -e. This will edit the current users crontab. If you are root and wish to edit a naughty cron from another user you use -u and specify the user.
Thats pretty much all there is to it. I’d love to here tips and how much people love/hate cron and why.
Happy Shell Scripting New Year,
Yakuake – “Pronunciation Key: yuh-kweyk”
Yakuake is a terminal emulator for KDE
“Why do we need another terminal emulator?”
I hear you ask.
Well, the Yakuake terminal emulator resembles the terminal from Quake (hence the name), except the only thing that gets owned when you run Yakuake is your to-do list.
Have you ever been fragged in Quake because you hit the Tilda key by accident?
Ever used this to your advantage while playing two player by pressing your opponents tilda key?
Have no idea what I’m talking about?
envision a terminal that magically pops up when you press a shortcut, hides when your not using it but retains the output / processes and does not show up in the task bar.
Sure there are old school ways of achieving the same thing, but Yakuake is convenient. It is based on Kommander so its highly configurable and customizable but it works right out of the package.
I use it on most of my machines and for quick tasks I find myself using a regular xterm less. If you want a quick easy access to a terminal I’d recommend trying Yakuake out, take a look at all of the keyboard shortcuts and see if there is any way you can make it work better for you.
I have my keyboard shortcuts set up so I can add new sessions, close sessions, rename sessions, move sessions and resize the terminal. It works great with the switch to session shortcuts that I also set up.
Its in the Fedora repositories, I’m sure its included in Debians 18,000 or so packages and probably Gentoo’s too, so give it a shot!
I’ll see what I can do about a video tutorial in the future to demonstrate the power of Yakuake.
Had a great time yesterday, a friend of mine came over. After dinner he was looking at some t-shirts since an advertisement had distracted him from his initial IMDB search. Some how this made him decide he wanted to make my desktop background a BSOD. I’m a big fan of the BSOD screensaver, and think its funny, whats even funnier is he figured out how to change my background on KDE (although it’s not that hard)
I saw the BSOD with the horrible background just staring at me. It was the classic, “there was an error processing your error”. I never see such things on my Linux box, I’m more used to failed reboots from failing to compile a kernel feature, so jokingly I click on the message box while laughing:
“Why won’t this go away”
Some people find humor in other peoples agony, this is why the TV series (and movies) Jackass do so well. I find humor in BSOD’s and hope that other Linux admin’s do to. But having a BSOD on your Linux box that’s not a screen saver is quite annoying, its like “Gates strikes back”
Here’s a poster I found amusing the other day:
Now, I know that Fedora is a community based operating system that Redhat just so happens to sponsor but I think there are some major problems with the release. Although I have been called “Bleeding Edge” I don’t think that I am quite there and actually I think I’m far from “Cutting Edge.”
I downloaded Fedora 9 on the day of its release to check it out. I started off by installing it onto a virtual machine. First time around the install failed for no reason, some Python error that I did not feel like debugging. I rebooted the VM , gave it another shot and it worked. The install process was pretty much the same as Fedora 8. I saw some minor differences but nothing that I can remember now. Once installed I fired it up and to say the least performance was not very good. I wanted to check out the KDE4, so I switched over. Nothing, the graphics support for the VMWare Toolbox driver is not good enough to really play with KDE4.
After toying with the Virtual Machine I decided to upgrade a test virtual machine from Fedora 8 to Fedora 9. The process to my surprise went smoothly. This was a vanilla Fedora 8 install with not too many bells and whistles. I administer a number of Fedora boxes and thought that I’d upgrade one that actually had software installed. The upgrade did not work, it failed and gave me an obnoxious error which had nothing to do with the task at hand. When I figure out exactly what the cause of the problem was, or if it is just a hardware issue I’ll report my findings here.
Despite feeling like I had not achieved too much I burned a copy of the DVD and installed it on my Desktop at the office. Its not the fastest machine on the planet but its no creeper. 1GB Ram, NVIDIA graphics and I think the upwards of 2GHz. The install went fine and gnome works great. I did not opt to install my window manager of choice (XFCE) since I was really wanting to play with KDE4. KDE4 installed fine and after switching desktops KDE worked. What’s the first thing I tried? You probably guessed it the Desktop effects. So, I try to enable them. No dice. So “I’ll just install the graphics card driver”
I thought since I know that it didn’t come bundled. This is where my troubles really began. The NVIDIA graphics will not compile on Fedora 9. Fedora 9 uses a version of XORG that has been stable for a while but NVIDIA has decided not to support yet. Thats exactly what you get when a vendor has control over source. Oh well.
I put up with the laggy graphics for a little while and tried to customize KDE. KDE4 to me seemed awfully buggy to be included as the only option for running KDE as a desktop. I happen to use KDE when not using XFCE and am quite happy with the 3.5 tree. My next problem apart was with Firefox. They include Firefox Beta 3, which I am undecided on. It crashed a number of times on me whist browsing since I hadn’t set anything up to do any real work on. I know that we would have to wait for Fedora 10 come out to see KDE4 and Firefox 3 if they were not included now but I didn’t see the legacy versions on the installer. For me Fedora 9 is not quite ready to use in a production environment.
For now I’m going to stick to Fedora 8 whilst providing feedback for 9. The moment that KDE, Firefox and XORG get patched I’m 100% there.
Fedora is not for every one but has any one else had any problems with Fedora 9 or interesting stories to share?
CHMOD is used to change permissions on a file. There are three types of permissions read, write, execute and there are three types that permissions can be set for owner, group and other.
It can be used with a symbolic representation or with an octal number that represents the bits. This blog post features on just the octal format. CHMOD works on most Linux file systems. It is also used on other operating systems such as BSD. Web designers and developers may be familiar with CHMOD as they have to set permissions when uploading files via FTP.
The octal notation can seem quite confusing but is actually very simple.
To figure out the octal format take the following table:
To figure out the octal method just add up the sum of what you want to set the permissions to.
If you would like to set the permissions for the owner to read, write execute and the group/other to read and execute you would do the following:
Its that simple. The way I remember the numbers to the corresponding permission is to remember that the number starts with 4 and is divided by two and then I repeat the following:
“For Read, Two Write, Execute”
meaning that 4 is read, 2 is write and the last (1) is execute.
There are graphical utilities that set permissions such as Thunar in XFCE and Konqeuror for KDE, but they normally do not allow you to change the permissions on multiple files at once.
If you have a whole directory full of files that you would like to change permissions on, you can simply do:
chmod 755 *
* is a wild card or regex and tells chmod to change permissions on all files.
If you would like chmod to go into directories and change permissions on files, the -R option is used.
chmod 755 -R *
will change permissions on all files and dive into the folders also.
chmod is an absolute must for system administrators and is good to know for home Linux users. If your experimenting with chmod be careful and do not use the -R option unless your absolutly sure you need to. I have accidentally used chmod to recursivly change permissions on a whole drive before. Lets leave it at this was not what I call a fun time since I had changed them to a very open 777.
Take that as your warning.