Does your camera show video correctly in cheese but shows captured video upside-down (inverted) in skype ? This is an issue a friend of mine experienced on his Asus K51AC-SX037D laptop on both Ubuntu and Debian Linux. As you can see in the picture above it is funny as with this bug the person looks like a batman 😉 As the webcam upside-down issue was present on both latest Ubuntu 11.10 and latest stable Debian Squeeze 6.02, my guess was other GNU / Linux rpm based distro like Fedora might have applied a fix to this weird Skype inverted video (bat human like) issue. Unfortunately testing the webcam with Skype on latest both Fedora 16 and Linux Mint 12 appeared to produce the same webcam bug.
A bit of research for the issue online and try outs of a number of suggested methods to resolve the issue led finally to a work around, thanks to this post Here is few steps to follow to make the webcam show video like it should:
1. Install libv4l-0 package
root@linux:~# apt-get --yes install libv4-0
...
Onwards to start skype directly from terminal and test the camera type:
This is the work around for 32 bit Linux install, most people however will probably have installed 64 bit Linux, for 64bit Linux installs the above command should be little different:
3. Edit the Skype gnome menu to substitute /usr/bin/skype Skype Launcher with /usr/local/bin/skype
Gnome 2 has a handy menu launcher, allowing to edit and add new menus and submenus (menus and items) to the Application menu, to launch the editor one has to click over Applications with last mouse button (right button) and choose Edit Menus
The menu editor like the one in the below screenshot will appear:
In the preceeding Launcher properties window, Command: skype has to be substituted with:
Command: /usr/local/bin/skype
For console freaks who doesn't want to bother in editting Skype Launcher via GUI /usr/share/applications/skype.desktop file can be editted in terminal. Inside skype.desktop substitute:
Exec=skype
with
Exec=/usr/local/bin/skype
As one can imagine the upside-down video image in Skype is not a problem because of Linux, but rather another bug in Skype (non-free) software program. By the way everyone, who is using his computer with Free Software operating system FreeBSD, Linux etc. knows pretty well by experience, that Skype is a very problematic software; It is often a cause for system unexpected increased system loads, problems with (microphone not capturing), camera issues, issues with pulseaudio, problem with audio playbacks … Besides the long list of bugs there are unexpected display bugs in skype tray icon, bugs in skype messanger windows and at some rare occasions the program completely hangs and had to be killed with kill command and re-launched again.
Another worrying fact is Skype's versions available for GNU / Linux and BSD is completely out of date with its "competitor" operating systems MS Windows, MacOS X etc. For people like me and my friend who want to use free operating system the latest available skype version is not even stable … current version fod download from skype's website is (Skype 2.2Beta)!
On FreeBSD the skype situation is even worser, freebsd have only option to run Skype ver 1.3 or v. 2.0 at best, as far as I know skype 2.2 and 2.2beta is not there.
Just as matter of comparison the latest Skype version on Windows is 5.x. Windows release is ages ahead its Linux and BSD ver. From a functional point of view the difference between Linux's 2.x and Windows 5.x is not that much different, what makes difference is is the amount of bugs which Linux and BSD skype versions contain… Skype was about 6 months ago bought by Microsoft, therefore the prognosis for Skype Linux support in future is probably even darker. Microsoft will not probably bother to release new version of Skype for their competitor free as in freedom OSes.
I would like to thank my friend and brother in Christ Stelian for supplying me with the Skype screenshots, as well as for being kind to share how he fixed his camera with me.
Every now and then I have to work on servers running CentOS or Fedora Linux. Very typical problem that I observe on many servers which I have to inherit is the previous administrator did not know about the existence of NTP (Network Time Protocol) or forgot to install the ntpd server. As a consequence the many installed server services did not have a correct clock and at some specific cases this caused issues for web applications running on the server or any CMS installed etc.
The NTP Daemon is existing in GNU / linux since the early days of Linux and it served quite well so far. The NTP protocol has been used since the early days of the internet and for centuries is a standard protocol for BSD UNIX.
ntp is available in I believe all Linux distributions directly as a precompiled binary and can be installed on Fedora, CentOS with:
[root@centos ~]# yum install ntp
ntpd synchronizes the server clock with one of the /etc/ntp.conf defined RedHat NTP list
server 0.rhel.pool.ntp.org
server 1.rhel.pool.ntp.org
server 2.rhel.pool.ntp.org
To Synchronize manually the server system clock the ntp CentOS rpm package contains a tool called ntpdate : Hence its a good practice to use ntpdate to synchronize the local server time with a internet server, the way I prefer to do this is via a government owned ntp server time.nist.gov, e.g.
[root@centos ~]# ntpdate time.nist.gov
8 Feb 14:21:03 ntpdate[9855]: adjust time server 192.43.244.18 offset -0.003770 sec
Alternatively if you prefer to use one of the redhat servers use:
[root@centos ~]# ntpdate 0.rhel.pool.ntp.org
8 Feb 14:20:41 ntpdate[9841]: adjust time server 72.26.198.240 offset 0.005671 sec
Now as the system time is set to a correct time via the ntp server, the ntp server is to be launched:
[root@centos ~]# /etc/init.d/ntpd start
...
To permanently enable the ntpd service to start up in boot time issue also:
[root@centos ~]# chkconfig ntpd on
Using chkconfig and /etc/init.d/ntpd cmds, makes the ntp server to run permanently via the ntpd daemon:
If you prefer to synchronize periodically the system clock instead of running permanently a network server listening (for increased security), you should omit the above chkconfig ntpd on and /etc/init.d/ntpd start commands and instead set in root crontab the time to get synchronize lets say every 30 minutes, like so:
The time synchronization via crontab can be also done using the ntpdate cmd. For example if you want to synchronize the server system clock with a network server every 5 minutes:
ntp package is equipped with ntpq – Standard NTP Query Program. To get very basic stats for the running ntpd daemon use:
[root@centos ~]# ntpq -p
remote refid st t when poll reach delay offset jitter
======================================================
B1-66ER.matrix. 192.43.244.18 2 u 47 64 17 149.280 41.455 11.297
*ponderosa.piney 209.51.161.238 2 u 27 64 37 126.933 32.149 8.382
www2.bitvector. 132.163.4.103 2 u 1 64 37 202.433 12.994 13.999
LOCAL(0) .LOCL. 10 l 24 64 37 0.000 0.000 0.001
The remote field shows the servers to which currently the ntpd service is connected. This IPs are the servers which ntp uses to synchronize the local system server clock. when field shows when last the system was synchronized by the remote time server and the rest is statistical info about connection quality etc.
If the ntp server is to be run in daemon mode (ntpd to be running in the background). Its a good idea to allow ntp connections from the local network and filter incoming connections to port num 123 in /etc/sysconfig/iptables :
-A INPUT -s 192.168.1.0/24 -m state --state NEW -p udp --dport 123 -j ACCEPT
-A INPUT -s 127.0.0.1 -m state --state NEW -p udp --dport 123 -j ACCEPT
-A INPUT -s 0.0.0.0 -m state --state NEW -p udp --dport 123 -j DROP
Restrictions on which IPs can be connected to the ntp server can also be implied on a ntpd level through /etc/ntp.conf. For example if you would like to add the local network IPs range 192.168.0.1/24 to access ntpd, in ntpd.conf should be added policy:
# Hosts on local network are less restricted.
restrict 192.168.0.1 mask 255.255.255.0 nomodify notrap
To deny all access to any machine to the ntpd server add in /etc/ntp.conf:
restrict default ignore
After making any changes to ntp.conf , a server restart is required to load the new config settings, e.g.:
[root@centos ~]# /sbin/service ntpd restart
In most cases I think it is better to imply restrictions on a iptables (firewall) level instead of bothering change the default ntp.conf
Once ntpd is running as daemon, the server listens for UDP connections on udp port 123, to see it use:
All the old school raptor addicts will be interested to hear Kazzmir (Jon Rafkind) a free software devotee developer has created a small game resembling many aspects of the original Raptor arcade game. The game is called Rafkill and is aimed to be a sort of Raptor like fork/clone. Originally the game was also named Raptor like the DOS game, however in year 2006 it was changed to current Rafkill in order to avoid legal issues with Apogee's Raptor.
The game is not anymore in active development, the latest Rafkill release is from January 2007, anyhow even for the 2012 it is pretty entertaining. The sound and music are on a good level for a Linux / BSD shoot'em'up free software game . The graphics are not of a top quality and are too childish, but this is normal, since the game is just one man masterpiece.
Rafkill is developed in C/C++ programming language, the game music engine it uses is called DUMB (Dynamic Universal Bibliotheque). By the way DUMB library is used for music engine in many Linux arcade games. DUMB allows the Linux game developer to develop his game and play a music files within different game levels in "tracked" formats like mod, s3m, xm etc.
The game is available in compiled form for almost all existent GNU/Linux distributions, as well as one can easily port it as it is open source.
To install Rafkill on Debian, Ubuntu, Xubuntu and Linux Mint en other Debian based distros
root@debian:~# apt-get install rafkill
Installing on Fedora and other rpm based is with yum
debian:~# apt-get install rafkill
...
Once rafkill is installed, in order to start it on Debian the only way is using the rafkill (/usr/bin/rafkill) command. It appears the deb package maintainer did not wrote a gnome launcher file like for example /usr/share/applications/rafkill.desktop Just to explain for all the GNOME noobs, the .desktop files are a description file GNOME reads in order to understand where exactly to place certain application in the (Gnome Applications, Places, System …) menu panel.
Even though it miss the .desktop, it is launchable via Applications menu under the Debian section e.g. to open it from the GNOME menus you will have to navigate to:
Applications -> Debian -> Games -> Action -> Rafkill
This "shortcut" to launch the game is quite long and hard to remember thus it is handy to directly launch it via xterm:
hipo@debian:~$ rafkill
or by pressing ALT+F2 and typing rafkill :
Starting the game I got some really ugly choppy music / sound issues. My guess was the fizzling sounds were caused by some bug with the sound portions streamed through pulseaudiosound system. To test if my presume is correct, stopped pulseaudio and launched rafkill once again:
This way the game was counting on ALSA to process sound en the sound was playing perfectly fine.
I solved this problem through small wrapper shell script. The script did kill pulseaudio before launching rafkill and that way solve gchoppy sound issues, once the game execution is over the script starts pulseaudio again in order to prevent all other applications working with pulseaudio.
Finally, I've placed the executable script in /usr/bin/rafkill :
Interesting in Ubuntu Linux, rafkill music is okay and I suppose the bug is also solved in newer Linux distributions based on Ubuntu. Probably the Debian Squeeze pulseaudio (0.9.21-4) package version has a bug or smth..
After the change the game music will be playing fine and the game experience is cooler. The game is hard to play. Its really nice the game has game Saves, so once you die you don't have to start from level 1.
I've seen rafkill rolling around on freebsd.org ftps under the ubuntu packages pool, which means rafkill could probably be played easily on FreeBSD and other BSDs.
Since its early days dosbox has elolved a lot. For all those who haven't heard of dosbox, it is x86 Free Software Linux / FreeBSD DOS emulator
DosBox supports, almost all the game classics we used top lay in oldschool times when DOS (Disk Operating System ) version was running on top of most personal computer.
The most spread versions of DOS people used to use on their PCs were Novell (DR-DOS) more rarely used, and MS-DOS (The Microsoft DOS ver.).
I'm sometimes being sentimental about the past so I remembered for Raptor – Call of the Shadows !
Having a bit of experience with DOSBox to run few DOS games I've decided to give a try with dosbox.
First I have to dig for this shareware, since this game is part of the sharewares, nowdays a binary version of it is freely distributed on the net. Finding the game however took me about 10 minutes, as most of the download links for Raptor, were either dead or required some kind of registration. After a bit of look I found it on an old torrent with few seeders and succeded downloading.
Nicely Raptor works out of the box directly launched with dosbox emulator. Dosbox has packages for most Linux distributions. I personally used it on my Debian Linux so installed via apt:
debian:~# apt-get install dosbox
...
The game works without any dosbox hacks, just download, unarchive and launch with dosbox:
hipo@debian:~$ wget https://www.pc-freak.net/files/Raptor_Call_of_The_Shadows_Apogee_arcade.tar.gz
...
hipo@debian:~$ tar -zxvf Raptor_Call_of_The_Shadows_Apogee_arcade.tar.gz
...
hipo@debian:~$ cd Raptor/
hipo@debian:/home/hipo/Raptor$ dosbox rap.exe
People like me 😉 who lived in that glorious times when DOS was a standard for a desktop operating system pretty much like MS Windows is today, certainly remember the awesome games produced by Apogee Software a company later known as 3D Realms
Apogee until this very day remain one of the greatest game creation companies in history of games. 3D Realms played a crucial role in development of PC game industry as well as has a great santimental value to probably million of old school arcade game addicts.
They can be ben undoubtedly can be praised for having created some of the most awesome arcade games for all times.
Some of the early hit games they created you probably know, few of the titles are:
Duke Nukem I, II
Arctic Adventure
Monster Bash
Stargunner
Commander Keen series
Wolfenstein 3D
Blake Stone
Terminal Velocity (Terminal Reality)
Shadow Warrior
Death Rally
Blood
Apogee was also notable for being a company to had established the so spread mostly during the late 80s up to the early years of the second millenium.
ShareWare model of distribution is an interesting phenomenon, that co-relates more or less with the ideas of Free Software. The idea of ShareWare games was games are distributed for Free and the end customer (gamer) is asked to pay for a game only if he likes it.
Some of the shareware published games was available for free download and play, however the game was only bundled with only a number of game levels to unlock the rest of the game levels you had to play some money.
The shareware games produced were then freely published and shared via dial up access BBS nodes (A text based Bulletin Board System similar to nowdays Forums). BBS has historically been the major way of sharing knowledge and exchanging ideas and opinions preceding the massive rise of the WEB. Today most computer users would probably even haven't heard about BBS, if you like to have a general idea on how BBSes seemed to look dahmer.vistech.net .
ShareWare started to loose speed with the decline of BBS and the emergence of Free Software.
Some of the conceptual ideas of ShareWare found its way in "Open Source & Free Software", and commercial companies like RedHat and SuSE.
If you have tried some other Apogee games with Dosbox on Linux and FreeBSD and you can positively confirm they work it will be great. In theory all of the DOS games of apogee should work fine with dosbox. Any feedback or game recommendations of your favourite games of the DOS years are mostly welcome in comments. I'm curious to hear what was your favourite DOS game. Maybe when I have time I'll prepare a list of my favourite games put them here 😉
I remember GNU / Linux, 11 years from now, times when ALSA was not standardly shipped with Linux. Back then ALSA still lacked good support for many SoundCards and was still a "baby project". In that time what we used to have sound on Linux was OSS – Open Sound System. OSS emerged right after the first ever Linux sound system VoxWare (formerly known as the Linux Sound Driver).
Back in those days OSS was used for multimedia support on both GNU / Linux and BSD based free OSes. It was few years later when I heard and used ALSA for a fist time and it wasn't really a love from first sigth.
One can easily find out by the name ALSA it is a system especially built for the Linux kernel and that's one of the reasosn why *BSD systems has their custom separate sound system. There is plenty of reasons why OSS was substituted with ALSA. Main reason was its commercial like license, OSS wasn't completely "open source" GPLed (free software), there was resctions on use of OSS for commercial goals.
With its emerge ALSA started to push away OSS slowly. Somewhere in 2003, alsa has officially entered the Linux kernel source and until 2005 it was the default standard for all GNU / Linux operating systems.
As of time of writting ALSA has become the only sound system to have support for multiple sound card devices for Linux. My experiences with ALSA, however ain't so nice if I take a look in my past experiences. Since the very beginning of using ALSA, I had plenty of troubles with configuring properly my sound card not to mention, even after configuring it the MIDI support was not there. Besides all the troubles main problems were stemming from the many applications still written to use OSS as sound system and hence with those sound was impossible with ALSA.The most problematic thing about apps written with OSS in mind was all of them tried to stream sound via /dev/dsp (OSS Digital Sound Processor), since alsa did not used /dev/dsp those programs was soundless.
On the other hand OSS was creating issues as well, one severe problem with OSS was the inability to stream multiple sounds simultaneously, because each sound stream required to pass voice through /dev/dsp and usually there was only one /dev/dsp.
The message;
/dev/dsp: Device or resource busy and the proceeding irritation that used to annoy us in the early GNU / Linux days had of course some raw workarounds hacks but generally the workaround did not fix problems always.
Introduction of alsa free us from /dev/dsp issues but on the other handy has created a whole ocean of new BIG problems … ALSA has modular structure and this imposes a great problem nowdays. The modular architecture is generally a good idea, however the way this was implemented within ALSA is far away from clear and easy to understand by the end user and therefore makes it very unintuitive and obscure. Alsa misses simplicity which somehow was partially in the days of OSS. Thinking over the general situation with Linux multimedia nowdays, I believe it was exactly ALSA Project responsible for the so delayed mass Desktop Linux adoption.
Many long year standing Linux users had certainly had the alsa troubles during new system installs (correct me if I'm wrong). The only fix to multiple soundcard initialization problems was to download alsa source and compile from source and hence made it hard and discouraging for people giving Linux a try. This kind of ALSA "brokenness" pattern continues even to this very day (in Debian) Linux and probably building the alsa system from source is among the good practices to have a functional Linux sound system…
With all said the historic reason why ALSA was not quickly adopted and still is not a preferred default system for many applications ported to Free Software OSes by commercial company vendors is clear. Its simply not working out of the box …
Hope some ALSA developers will read this post work on changing the crazy structure of ALSA over complexity. ALSA needs automate way to solve issues with itself, the configuration should be more trivial and unified if Linux has to become more attractive for Desktop adoption.
Anyways, after the few words of history and indicating my pesonal observations on ALSA. I will proceed and explain few things on how ALSA can be configured to support and play nice with OSS dependant programs as well some basic explanations on common incompatibility between esd and pulseaudio and how this can be fixed;.
To assure nowdays OSS API built programs and games would work with Alsa its necessery to have installed;
ALSA wrapper for OSS applications
On Debian, Ubuntu, Fedora and most Linux distributions the Alsa OSS compatability layer comes under a (deb / rpm) package named alsa-oss
To install OSS compatability on Debian, Ubuntu and the like Debian based distributions issue:
Note! The three modules has to be separately build using kernel source at most cases and does not come with most Linux distributions, so on many installations (including my current), they will be missing. If for you they load properly or you have customly build them add them also to load on system boot, like so:
The Linux sound situation becomes even more messy when ESD enters the scene. Many of the novice new Linux users certainly don't remember (Enlightened Sound Daemon) . ESD historically preceded PulseAudio . Hence it will be good to mention ESD was used for few years in GNOME and in around 2006-2007 it was substituted by PulseAudio. Many applications, however who was ported or written for Linux especially (the proprietary ported ones) was already built to work with ESD and even though newer GNOME releases was fully using pulseaudio, this (non free software apps and games) were still depending on ESD.
The situation was partially fixed by creation of module for pulseaudio which added emulation support for esd . This was done by a module library for pulseaudio called libprotocol-esound.so The package for almost all Linux distributions which does the esd emulation via pulse is pulseaudio-esound-compat . In latest Fedora Linux pulseaudio-esound-compat is installed by default. In Debian and other Linux distributions it might need to be installed via apt with;
pulseaudio-esound-compat solves some of the ESD app incompability but not always … Handy tool also worthy to mention in solving PulseAudio, OSS incompatibility issues is padsp
padsp is helpful in solving obsolete issues with OSS applications (trying to access /dev/dsp) and therefore unable to communicate with Pulseaudio padsp – is a PulseAudio OSS Wrapper.
An example where padsp is helpful is in case of /dev/dsp errors like:
/dev/dsp: Device or resource busy
Could not open /dev/dsp
Another common problem with sound on Linux is when running windows applications (running windows games with wine). Quite often sound fails to work since wine tries to directly communicate with alsa and fails because alsa sound channel is taken by pulseaudio.
To workaround wine issues with pulseaudio, one of the solutions is to temporary stop pulseaudio, before running the wine emulated application:
hipo@debian:~$ pulseaudio --kill
Later on when the windows wine emulation is completed, pulseaudio has to be started once again in order to make Pulseaudio applications produce sound again, e.g. one has to issue:
hipo@debian:~$ pulseaudio --start
Alternative way to workaround wine sound issues is by using a script to kill pulseaudio every second. Here is fix_pulseaudio_wine_sound_probs.sh script
This script was reported by many people as fix to problems with wine games failing to play sounds and music, anyhow I personally prefer using the stop / start pulseaudio method.
The picture below is taken from Wikipedia and illustrates, clearly the intergalactical complexity of sound systems on Gnu / Linux and BSD
I just hope one day this (OSS, ALSA, esd, Pulseaudio) mess will be over! In the mean time I hope my suggested work arounds helps someone. If someone has a better more unified script or solution please share in comments
Some might remember Psychosis Lemmings that we used to enjoy back in the glorious days of DOS 😉 I remember Lemmings used to be among the played game in one line with other top arcades like Dangerous Dave, Commander Keen, Xenon etc. The game used to be quite unique for the time and it was quite cool that it worked on quite old machines lime my old 8086 XT with 640kb of memory. It even supported two player mode! 😉
I was happy to find out actually Lemmings remake is available in the Free Software OS realm . These Lemmings clone game is called Pingus Instead of governing a group of lemmings which had to move to an exit door by making a save path using various tools and combination of team member character skills, the main heroes in Pingus are cute little penguins 😉
Pingus is built on TOP of SDL libraries and has a combination of awesome graphics and enjoyable music soundtrack and as a game play is a way better than its original predecessor. If i have to to rank this game I would put it among the best 20 free software games ever produced for Linux / BSD.
pingus is available for almost all kind of Linux distritubions as well as is included in the FreeBSD port tree:
On Debian its available as a package ready to be installed with aptitude or apt by issuing:
debian:~# aptitude install pingus
For FreeBSD pingus is installed via ports tree, by running cmds:
freebsd# cd /usr/ports/games/pingus
freebsd# make install && make install clean
By default pingus will run in a Windowed mode, to run the game in fullscreen you will have to run it with the -f switch via terminal, or by pressing ALT+F2 in GNOME and typing:
$ pingus -f
The game is quite hard to complete in that resembling the lemmings. It has an embedded Mapeditor , by which new levels can be easily constructed and sent to the game developers (in that way helping the game development).
Playing Pingus has few benefits, one is it can be nice to kill some boredom (for sysadmins) or / and bring some good past gaming memories. It's also good for developing some elder people strategic thinking as well as very suitable for little children to help develop their intellectual (thinking) in solving complex consequential tasks. Pingus could also be beneficial for teens to develop organizational and math skills.
Do you remember the old arcade spaceship shooter Xenon 2 Megablast? I do 😉 For all those who are too young to remember, here are two screenshots:
Even though Xenon 2 Megablast original can now be played using dosbox DOS emulator. Its interesting to mention I've found two Linux games that more or less can be qualitified to resemble Xenon 2. The games are Native Free Software games and existing in package repositories of most Linux distributions and *BSD port trees.
Geki 2 and Geki 3 are of a less quality to Xenon but still, the game experience is nice and is among the Arcade shooter games to bring you fun in the boring days if you're on GNU / Linux or FreeBSD Free OS platforms.
Installing Geki2 and Geki3 on Debian and Ubuntu Linux is standard with apt:
debian:~# apt-get install geki2 geki3
...
On Debian GNU / Linux , after installed the games would not create GNOMEApplications -> Games -> game startup shortcuts, however the game startups will get added in GNOME Applications Menu under:
Applications -> Debian -> Games -> Action -> Geki 2
and
Applications -> Debian -> Games -> Action -> Geki 3
The games can be launched also manually with commands:
geki2
or
geki3
Geki 2 is a way closer to Xenon 2 as it has similar look and feel and the same vertical direction the spaceship is navigated. In Geki 3 still the shoot 'em' up spaceship like arcade is present, however instead of penguin you have to fly a flying penguin, as well as the spaceship move direction is horizontal.
Both the games have the same sound and music effects. The game music and effects are not of top quality but are not bad. In general the games surely gives some of the arcade atmosphere.
Geki 2 Xenon 2 Megablast like on Debian Linux
In the tradition of the arcade games at the end of each level in both games you face the Level Boss Enemy, you should destroy.
As you can see in below's screenshot the overall graphics of GEKI 3 is poorer while compared to GEKI 2
still GEKI 2 gampley is fun and addictive and I would say not less enjoyable than GEKI 2. At times I even think that Geki 3 is more fun because it is more dynamic.
Maybe other reason, why I enjoyed more Geki 3 is also the fact that Geki 2 is a way harder to play. Dying only 3 times in the game you get GAME OVER and the next game you're started from the beginning of the same level you died in …
Something really annoying that affects both the games; there is no option to play them in Fullscreen mode! ARGH!
Game controls for Geki2 and Geki3 are identical as follows:
Up - Arrow up key
Down - Down arrow key
Right - Right arrow key
left - Left arrow key
Shoot - z or Space
Pause - s
Geki2 and Geki3 are fun and can kill some time, but definitely aren't that (professional) as other spaceship shoot'em'up arcades for Linux and BSD. Games like Starfighter , Critical Mass or powermanga . Lest that they are two worthy to install and play on your Free Software OS.
UNetbootin is a nice easy to use Free Software Universal mutli OS program that makes creation of Bootable USB Stick Linux, FreeBSD, NetBSD and other free operating systems a piece of cake
UNetbootin support the three major operating system architectures Windows, Mac OS X and GNU / Linux . In Debian and Ubuntu based distributions Unetbootin is available as a deb binary package:
debian:~$ dpkg -l |grep -i 'usb' |grep -i 'install'
ii unetbootin 471-2
installer of Linux/BSD distributions to a partition or USB drive
To install it with apt:
debian:~# apt-get install unetbootin
...
debian:~# unetbootin
Alternatively for all those who prefer to run it via the GNOME Application menu follow to the menu path:
Applications -> System Tools -> Unetbootin
If the program is launched with non privileged account (like via GNOME Application menu), in order to to properly tamper with any connected USB Flash drive you will be asked about the super user password.
The shipped uniboot version in current Debian stable version Squeeze is 471-2 is a bit outdated. For everyone eager to use the latest version which as of time of writting is 565 check out UnetBootin’s Official Homepage on SourceForge
Installing the distributed binary of unetbootin downloadable from its website is a trivial one. Simply download the file from the Download (for Linux) link and run the binary unetbootin-linux-565:
debian:~$ ./unetbootin-linux-565
There is one annoying thing about the latest downloadable (static compiled) unetbootin version, it was built to run using KDE’s QT library and therefore the interface that poped up while trying it was KDE like, pitily did not take advantage of my native GNOME GTK2 library :
Though this little note, unetbootin developers has done a truly great job! I tried unetbootin and was more than pleasently surprised that it prepares bootable USB sticks with only 4 mouse clicks!!! 😉 The program worked out of the box without any external or additional hacks like many of the programs I daily use it just worked 😉
UNetbootin has a thoroughful list of Free Software operating system distributions in the distributions list. Many of the offered Open Source & Free Software distributions has even possibility of installing a multiple versions of the respective distro.
Here is a complete list of all the Free & Open Source Operating Systems, unetbootin program can burn and make bootable on USB stick.
1. Ubuntu
2. Debian
3. Fedora
4. PCLinuxOS
5. Linux Mint
6. Sabayon Linux
7. Gentoo
8. OpenSUSE
9. MEPIS
10. Zenwalk
11. Arch Linux
12. Slax
13. Dream Linux
14. Damn Small Linux
15. SliTaz
16. Elive
17. CentOS
18. Puppy Linux
19. Mandriva
20. FreeBSD
21. LinuxConsole
22. Frugalware Linux
23. NetBSD
24. xPUD
25. gNewSense
26. GeeXboX
27. Gujin
28. Kaspersky Rescue Disc
29. NimbleX
30. Sabayon Linux
31. Puppy Linux
32. Mandriva
33. SuperOS
34. Xubuntu
35. Parted Magic
36. Super Grub Disk
37. Smart Boot Manager
38. 0phcrack
40. FreeNAS
41. NetBootCD
42. FreeDOS
43. Dr. Web Antivirus
44. CloneZilla
45. Kubutun
46. BackTrack
To burn and make bootable on the USB flash drive any of the listed distributions, choose the distribution name and version number as well as the Drive: (which usually will be selected by default to the first sticked USB drive let’s say /dev/sdb1). Afterwards press on the OK button and that’s it, lay down your back and wait until the distribution is downloaded from the Internet, burned into the USB pendrive and made bootable. I’ve tested Unetbootin with two distributions;
1. Xubuntu 10_04_live and; 2. Fedora 13
Both of the distributions got burned properly to the USB drive usng the CD images and booted fine on a Packard Bell notebook on. Having an USB drive with LiveCD GNU / Linux or BSD everywhere with you is hand and is a sort of substitute to the old linux boot floopy disk of Tomsrtbt linux distribution, I used to keep everywhere with me . Now I can move to any PC installed with Windows and use my preferred Free Software OS using an USB Stick.
Besides that, there are laptops whose CD-ROM / DVD-ROM drive is broken and therefore if one wants to re-install an improperly working Windows XP / Vista / 7 and substitute with Free operating system this task is only possible using USB Flash Disk or NetBoot Install. Installing using USB has its advantageous as you don’t depend on the network as well as the installation from USB is in most of the cases few times faster. There are plenty of other USB Linux installer programs, most of them however are only available with a Windows version.
Here are few prgrams which can be used to burn a number of Linux and *BSD installations using Microsoft Windows to create Linux / BSD liveUSB:
Universal USB Installer – http://live.learnfree.eu/download
YUMI – Your Universal Multiboot Installer – http://www.pendrivelinux.com/yumi-multiboot-usb-creator/
xBOOT – http://sites.google.com/site/shamurxboot/
I was happy to find out ’bout the existence of Universal USB Installer (this proggie written in Python) is made by a Bulgarian mate! Proud to be Bulgarian 😉 Universal USB Installer is actually multiplatform since written in Python and therefore can be used to burn a LiveUSB on GNU / Linux and (possibly on FreeBSD?)I would be glad to get feedback from other people who had experience with programs to prepare LiveUSB bootable sticks on Free Software OSes. Does anybody tried that on who *BSDs? Cheers 😉
I just read the lwn.net – Linux Weekly news ‘s website the very sad news that one of the greatest modern day computer heroes Dennis MacAlistair Ritchie after a long illness has passed away in his home.
The original notification for this grieving news are on Rob Pike’s Google Plus wall , this is the original message:
Rob Pike - 1:02 AM - Public
I just heard that, after a long illness, Dennis Ritchie (dmr) died at home this weekend. I have no more information.
I trust there are people here who will appreciate the reach of his contributions and mourn his passing appropriately.
He was a quiet and mostly private man, but he was also my friend, colleague, and collaborator, and the world has lost a truly great mind.
For all those who haven’t heard about Dennis Ritchie , he was a computer scientist who developed the C Programming language and had an immeasurable influence on all kind of Modern programming.
Dennis worked on the development of Unix’s predecessor Multics as well as with Ken Thompson worked together in Bell Labs and are practically the fathers of UNIX. Unix the Seventh Edition source code has later become the basis for the early UNIX BSD distributions. Among the most important technical contributions Dennis has done is the introduction of a Streams mechanism – pipes – (as called today in GNU/Linux and BSD and other unices). Ritchie’s C Language creation on top of Ken Thompson’s B Programming language has been standartized and become the de-facto standard for almost every modern existing OS around. Moreover dmr has been among the co-creators of Plan 9 Operating system (which is currently open-source distributed) as well as coded a few bits for the Inferno OS which today is known under the code name Vita Nuova
dmr (the hacker nickname of Dennis) lines up across the most notable computer hackers of all times. He received U.S. national Medal of Technology in 1999 from president Bill Clinton for his contributions to co-inventing the UNIX operating system and the creation of C Language
To sum it up DMR is just an “icon” in the computer geek world and his memory will surely live forever in the hacker undeground and computer geek culture.
A few quotes dmr is so famous with:
"I am not now, nor have I ever been, a member of the demigodic party."
"Usenet is a strange place."
"UNIX is very simple, it just needs a genius to understand its simplicity."
"C is quirky, flawed, and an enormous success."
"We really didn't buy it thinking we'd have this enormous investment."
Here is also a short video telling a few words of UNIX history and showing Dennis Ritchie in his UNIX development years:
One of the websites hosted on a server I currently manage has a cache directory which doesn’t take much space but tens of thousands of tiny files. Each second a dozen of files are created in the cache dir. Hence using a hard disk directory puts some serious load on the server consequence of the many fopen and fcloseHDD I/O operations.
To get through the problem, the solution was obvious use a directory which stores its information in memory. There are of course other benefits of using a memory to store data in as we all know as access to RAM is so many times faster.
GNU/Linux is equipped with a tmpfs since kernel version 2.4.x, primary usage of tmpfs file system across many G / Linux distributious is the /tmp directory.
Some general tmpfs information about tmpfs is explained in mount’s manual e.g.: man mount, a good other reading is the tmpfs kernel documentation file
An implementation of tmpfs is /dev/shm .
/dev/shm is a standard memory device used among Linuces, its actually an ordinary directory one can list with ls . /dev/shm is used as a “virtual directory” memory space. Below is an output of /dev/shm from my notebook, one can see few files stored in memory which belong to the pulse audio linux architecture:
linux:~$ ls -al /dev/shm
ls -al /dev/shm/total 7608drwxrwxrwt 2 root root 160 Oct 10 18:05 .
drwxr-xr-x 16 root root 3500 Oct 10 10:57 ..
p-w------- 1 root root 0 Oct 10 10:57 acpi_fakekey
-r-------- 1 hipo hipo 67108904 Oct 10 17:20 pulse-shm-2067018443
-r-------- 1 hipo hipo 67108904 Oct 10 10:59 pulse-shm-2840042043
-r-------- 1 hipo hipo 67108904 Oct 10 10:59 pulse-shm-3215031142
-r-------- 1 hipo hipo 67108904 Oct 10 18:05 pulse-shm-4157723670
-r-------- 1 hipo hipo 67108904 Oct 10 18:06 pulse-shm-702872358
To measure the size of /dev/shm across different Linux distriubtions one can use the usual df cmd, e.g.:
[root@centos: ~]$ df -h /dev/shm
Filesystem Size Used Avail Use% Mounted on
tmpfs 16G 0 16G 0% /dev/shm
Above I show a df -h /dev/shm output from a CentOS server equipped with 32 GB of memory, as you can see CentOS has reserved half of the size of the system memory (16GB) for the purposes of creating files in memory through /dev/shm. The memory is dynamically assigned, so if its not use the assigned memory by it can still be used for the purposes of the services running (which by the way is very nice).
Accoring to what, I’ve read in wikipedia about tmpfs, tmpfs defaults in Linux to half of the system physical memory. However I’ve noticed Debian Linux hosts usually reserve less memory for /dev/shm, on my personal notebook Debian /dev/shm is only 1 Giga, where on a Debian running server, Debian automatically has set it to the humble 2GB. Setting less by the way as with the Debian example, is a rather good idea since not many desktop or server applications are written to get actively advantage of the virtual /dev/shm directory.
One can directly drop files in /dev/shm which will immediately be stored in memory, and after a system reboot the files will disappear. Let’s say you zip archive file, testing.zip and you like to store the file in memory to do so, just copy the file in /dev/shm.
linux:~$ cp -rpf testing.zip /dev/shm
You don’t even need to be root to copy files in the “virtual memory directory”. This is a reason many crackers (script kiddies), are storing their cracking tools in /dev/shm 😉
A rather funny scenario, I’ve witness before is when you list /dev/shm on some Linux server and suddenly you see a tons of brute forcing tools and all kind of “hack” related stuff belonging to some system user. Sometimes even this malicious script tools belong to the root user…
Now as I’ve said a few words on how linux’s tmpfs works here is how to mount a directory which cache content will be stored in volatile memory:
linux:~# mount -t tmpfs -o size=3G,mode=0755 tmpfs /var/www/site/cache
As you can see the above command will dynamically assign a tmpfs directory taking up from the system RAM mem which could expand up to 3GB within the system memory.
Of course before mounting, its necessery to create the /var/www/site/cache and set proper permissions in the above example I use /var/www/site/cache with a default permissions of 755 which is owned by the use with which the Apache server is running, e.g.:
Using a tmpfs is very handy and have many advantages, however one should be very careful with the data stored inside a tmpfs dir resource, all data will be lost in case of sudden system restart as the data is stored in the memory. One other problems one might expect with tmpfs would be if the assigned virtual disk space gets filled with data. It never happened to me but, I’ve red online some stories that in the past this led to system crashes, today as the dox I’ve checked prescribed overfilling it will start swapping make the system terribly sluggish and eventually afred depleting the reserver swap space will start killing processes.
Using tmpfs as a cache directory is very useful on servers running Apache+PHP/Perl/Python/Ruby etc. as it can be used for stroring script generated temorary data.
Using a tmpfs can signifantly decrease server i/o created disk overheads.
Some other application I can think of though, I haven’t tested it would be if tmpfs mounted directory is used to store scripting executable files, copied after restart. Executing the script reading it directly from the “virtual directory” could for sure have very good impact especially on huge websites. One common service which takes advantage of the elegancy of tmpfs nowdays almost all modern GNU/Linux has is udevd – The Linux dynamic device management. By the way (man udev) is a very good and must read manual especially for Linux novices to get a good basic idea on how /dev/ mamagement occurs via udev.
To make permenant directory contained in memory on Linux the /etc/fstab file should be used.
In order to mount permanently a directory as a memory device of a size of 3GB with 0755 permissions in /var/www/site/cache, as shown in the earlier example, one can use the command:
This will assure the directory stored in memory would be recreated on next boot.
Nowdays the use of tmpfs is constantly growing, I’ve seen it to be used as a way to substitute ordinary disk based /tmp with a tmpfs directory contained in memory in Cloud Linux OS. The applications of tmpfs is pretty much to the imagination of the one who wants to get advantage of it. For sure using tmpfs will be seen by the Linux GUI programs.
Going to FreeBSD and the BSD world, tmpfs is also available, however it is still considered a bit experimental. To get use of tmpfs to gain some performance, one should first enable it via bsd’s /etc/rc.conf:
freebsd# echo 'tmpfs_load="YES"' >> /etc/rc.conf
Mounting a directory permanently using tmpfs persmanently it again is doable via /etc/fstab to add a new directory inside memory with tmpfs: is done with adding:
The native equivallent of tmpfs in FreeBSD is called mdmfs. As I said it is slower than tmpfs but rock solid.
To mount a 4gigabyte size mdmfs “ram directory” on BSD from csh:
freebsd# mdmfs -s 4g md /var/www/site/cache
Mounting a directory permanently using tmpfs persmanently it again is doable via /etc/fstab to add a new directory inside memory with tmpfs: is done with adding:
The native equivallent of tmpfs in FreeBSD is called mdmfs. As I said it is slower than tmpfs but rock solid.
To mount a 4gigabyte size mdmfs “ram directory” on BSD from csh:
freebsd# mdmfs -s 4g md /var/www/site/cache
Mounting a directory permanently using tmpfs persmanently it again is doable via /etc/fstab to add a new directory inside memory with tmpfs: is done with adding:
freebsd# echo 'md /var/www/site/cache mfs rw,-s4G 2 0' >> /etc/fstab
There are some reports of users who presumable use it to increase the ports / kernel compile times, but I haven’t tried it yet so I don’t know for sure
In huge corporations like Google and Yahoo tmpfs is certanly used a lot as this technology can dramatically can improve access times to information.I’m curious to know for some good ways to get use of tmpfs to improve efficiency. If someone has some readings or has some idea please shar with me 😉
I remember GNU / Linux, 11 years from now, times when ALSA was not standardly shipped with Linux.
Though this little note, unetbootin developers has done a truly great job! I tried unetbootin and was more than pleasently surprised that it prepares bootable USB sticks with only 4 mouse clicks!!! 😉
