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Showing posts with label GNU/Linux. Show all posts
Showing posts with label GNU/Linux. Show all posts
Saturday, February 15, 2014
Should Microsoft Windows Free?
Few days ago, I read this article "Microsoft should get used to giving Windows away for free" written by Tony Bradley on TechRepublic. I like that idea. If Microsoft can not make Windows free as Ubuntu Linux, at least it should be free upgrade or low cost like Mac OS/X 10.7
Wednesday, September 11, 2013
Connect to Windows Share from Ubuntu
When I attempted to connect to Windows Share from Ubuntu 12.04, I got this error message: "Failed to retrieve share list from server"
Found solution from UbuntuForums.org (http://ubuntuforums.org/showthread.php?t=1082148&page=12&p=9762937#post9762937). Enter "smb://192.168.123.123" where 192.168.123.123 is the IP address of Windows Share, it bring up the list of shared folders on Windows machine.
Now, I just entered the user name and password to get in.
Found solution from UbuntuForums.org (http://ubuntuforums.org/showthread.php?t=1082148&page=12&p=9762937#post9762937). Enter "smb://192.168.123.123" where 192.168.123.123 is the IP address of Windows Share, it bring up the list of shared folders on Windows machine.
Now, I just entered the user name and password to get in.
Friday, May 17, 2013
Android Studio
On Google IO 2013, Google introduced Android Studio, based on IntelliJ IDEA, a new tool for Android developers. I liked it. Since it was a preview version, Google noted:
On Mac OS/X with Java 1.6.0_45, I got Android Studio ran immediately without hicup. After I made a new simple project to test, I could not load any Android Virtual Device. To work around, I opened Android Virtual Device Manager from Eclipse Juno to load the Android Application launched from Android Studio.
On Windows Vista with JRE 7 installed only, Nothing running after executed Android Studio (c:\android-studio\studio,exe) application. Tried to replaced Oracle JRE 7 with Oracle JDK 7, no luck. Solution: Added environment variable JAVA_HOME with value "C:\Program Files\Java\jdk1.7.0_21) to system variables. Further reading:
Caution: Android Studio is currently available as an early access preview. Several features are either incomplete or not yet implemented and you may encounter bugs. If you are not comfortable using an unfinished product, you may want to instead download (or continue to use) the ADT Bundle (Eclipse with the ADT Plugin).As soon it posted on developer.android.com, I downloaded and installed on three platforms: Ubuntu 13.04, Mac OS/X Lion 10.7.5 and Windows Vista. On Ubuntu 13.04 with OpenJDK 1.7, I got this error message:
'tool.jar' is not in Android Studio class path. Please ensure JAVA_HOME points to JDK rather than JRE.I have no problem using Eclipse Juno (4.2.2) for Android development on this machine. Ran android-studio/bin/studio.sh at a terminal, there was a warning:
WARNING: You are launching the IDE using OpenJDK Java runtime. ITS KNOWN TO HAVE PERFORMANCE AND GRAPHICS ISSUES! SWITCH TO THE ORACLE(SUN) JDK BEFORE REPORTING PROBLEMS!Downloaded and switched to Oracle (Sun) JDK from OpenJDK on Ubuntu 13.04 according to Hendré's blog, problem solved.
On Mac OS/X with Java 1.6.0_45, I got Android Studio ran immediately without hicup. After I made a new simple project to test, I could not load any Android Virtual Device. To work around, I opened Android Virtual Device Manager from Eclipse Juno to load the Android Application launched from Android Studio.
On Windows Vista with JRE 7 installed only, Nothing running after executed Android Studio (c:\android-studio\studio,exe) application. Tried to replaced Oracle JRE 7 with Oracle JDK 7, no luck. Solution: Added environment variable JAVA_HOME with value "C:\Program Files\Java\jdk1.7.0_21) to system variables. Further reading:
- Getting Started with Android Studio. Need to read this page thoroughly to save time.
- IntelliJ IDEA and Android Studio FAQ. This FAQ is good.
Friday, February 22, 2013
Verdana, Aria fonts on Ubuntu
Install Microsoft core fonts package by running this command in terminal:
For more info read http://www.tuxgarage.com/ 2011/11/ttf-mscorefonts- installer-ubuntu.html
Sunday, October 21, 2012
Install Android Development Tools on Ubuntu 12.10 (Quantal Quetzal)
- First thing first. Make sure Java Development Kit (JDK) install. Go to Terminal and type 'Java -version' to check. You should see the following:
java version "1.7.0_07"
OpenJDK Runtime Environment (IcedTea7 2.3.2) (7u7-2.3.2a-1ubuntu1)
OpenJDK Server VM (build 23.2-b09, mixed mode) - If Java Development Kit is not installed, you can install it from Ubuntu Software Center. Click on Ubuntu Software Center icon from left side bar and search for Java. Here, I selected 'OpenJava JDK 7 runtime'
- Go to http://www.eclipse.org/downloads/ to download Eclipse Classic 4.2.1 (Juno)
- Go to your downloads folder and extract it. Move 'eclipse' folder to your home directory.
- Launch Eclipse 4.2.1 (Juno) from 'eclipse' folder.
- Install Android Developer Tools (ADT) plugin for Eclipse. Click on Help -> Install New Software and add the URL 'https://dl-ssl.google.com/android/eclipse/' on the input text box next to 'Work with' and click the 'Add' button.
- Download and install Android SDK from Eclipse 4.2.1. Click on Window -> Android SDK Manager. If Android SDK is not install, Eclipse will display a windows like this:
Otherwise, select the existing Android SDK and specify location if it already installed. - Go to Windows -> AVD Manager to make at least one Android Virtual Device (AVD). Here is the screen shot for AVD using Galaxy Nexus skin.

Thursday, October 18, 2012
How to upgrade to Ubuntu 12.10 (Quantal Quetzal) from Ubuntu 12.04 LTS (Precise Pangolin)
The latest version of a great Linux distribution, Ubuntu 12.10 code name Quantal Quetzal, release today. You should receive the notification of this new release on Update Manager. If not:
- Go to Settings on Update Manager and change 'Notify me of a new Ubuntu version' to 'For any new version''
- Check again. You will see a notification 'New Ubuntu release 12.10 is available'.
- Click the 'Upgrade' button to upgrade to Ubuntu 12.10
Sunday, April 22, 2012
How to rename multiple files in Ubuntu?
Using the rename command and Perl expression. In the terminal:
To rename all upper case file names with extension .JPG to lower case
Test first.
rename -n 'y/A-Z/a-z/' *.JPG
Execute and show the operation.
rename -v 'y/A-Z/a-z/' *.JPG
To remove all colon character out of of the file name:
rename -vn 's/[:]//g' *
To remove all non-alphanumeric characters:
rename -vn 's/[^A-Za-z0-9._]//g' *
For more inforation, type 'man rename'
To rename all upper case file names with extension .JPG to lower case
Test first.
rename -n 'y/A-Z/a-z/' *.JPG
Execute and show the operation.
rename -v 'y/A-Z/a-z/' *.JPG
To remove all colon character out of of the file name:
rename -vn 's/[:]//g' *
To remove all non-alphanumeric characters:
rename -vn 's/[^A-Za-z0-9._]//g' *
For more inforation, type 'man rename'
Sunday, March 25, 2012
Unity Launchpad error in Ubuntu 12.04 LTS (Precise Pangolin) Beta 1
In the last couple days, I encountered the Unity Launchpad error in Ubuntu 12.04 LTS (Precise Pangolin) Beta 1. I got the error dialog box displayed, closed it, got a blank screen, nothing there. No launchpad.
How I got into the terminal or launched the application? How I fixed it?
Launched the keyboard shortcut by pressed these keys together <Ctrl><Alt>T
Now in the terminal, I ran these commands:
~$ sudo apt-get update
~$ sudo apt-get upgrade
I thought the new updates would fix it. Still no launchpad. I typed this command at the terminal
~$ unity
The launchpad launched. Still some glitches. Reboot. Repeated these processes above couple times, it worked.
How I got into the terminal or launched the application? How I fixed it?
Launched the keyboard shortcut by pressed these keys together <Ctrl><Alt>T
Now in the terminal, I ran these commands:
~$ sudo apt-get update
~$ sudo apt-get upgrade
I thought the new updates would fix it. Still no launchpad. I typed this command at the terminal
~$ unity
The launchpad launched. Still some glitches. Reboot. Repeated these processes above couple times, it worked.
Wednesday, March 21, 2012
Read Error in LibreOffice
If you cannot open the LibreOffice document due to read error as the picture below
Un-install LibreOffice version 3.4 and install LibreOffice 3.5 will solve the problem. I got this problem when saved a file in LibreOffice 3.5 in Mac and attemped to open it in Ubuntu.
Un-install LibreOffice version 3.4 and install LibreOffice 3.5 will solve the problem. I got this problem when saved a file in LibreOffice 3.5 in Mac and attemped to open it in Ubuntu.
Sunday, October 23, 2011
Upgrade to Ubuntu 11.10 (Oneiric Ocelot)
I upgraded my Ubuntu 11.04 Natty Narwhal to Ubuntu 11.10 beta 2, code name Oneiric Ocelot, on Oct. 12, before official release few days. Here are my own experience:
- Make sure you know the admin password for PhpMyAdmin, if installed, before you upgrade. I forgot this password and it took me almost half hour to get out the infinite loop :(
- An hour for download and another hour to install.
- Remote desktop 'tsclient' was removed. Used 'RDesktop' or 'Remmina' instead. After using Remmina Remote Desktop client, I liked it. It's better than 'tsclient'
- Somehow the trash icon in launchpad associated with VLC media. Uninstalled VLC resolve this issue.
Saturday, October 15, 2011
How to upgrade VirtualBox 4.0.12 to 4.1.4 on Ubuntu 11.04
Oracle released VirtualBox 4.1.4, a maintenance release of VirtualBox 4.1 which improves stability and fixes regressions, on Oct 3rd, 2011. Using 'sudo apt-get update' and 'sudo apt-get upgrade' will not upgrade your Oracle VirtualBox (https://www.virtualbox.org/) from 4.0.12 to 4.14. To upgrade:
- Backup your virtual machine by press <ctrl>-E to export appliance
- Go to Ubuntu Software Center to uninstall current version
- Install new version Oracle VM VirtualBox 4.1.4
- Install Oracle VM VirtualBox Extension Pack
- Run virtual machine and apply new version of Oracle VM VirtualBox Guest Addition 4.1.4r74291
Sunday, July 24, 2011
Disable Mousepad on Dell Inspiron 1545 with Ubuntu 11.04
After upgraded to Ubuntu 11.04, I could not use the command 'sudo modprope psmouse -r' to disable. Executed that command cause my laptop hung.
This discussion "Ubuntu 11.04 with Gnome on Dell 6510: cannot disable touchpad" on UbuntuForums.org offered me a solution. Here, what I did on on my computer:
user@vn-software:~$ xinput list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ Logitech USB Receiver id=10 [slave pointer (2)]
⎜ ↳ Logitech USB Receiver id=11 [slave pointer (2)]
⎜ ↳ ImPS/2 ALPS GlidePoint id=13 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
↳ Video Bus id=6 [slave keyboard (3)]
↳ Power Button id=7 [slave keyboard (3)]
↳ Sleep Button id=8 [slave keyboard (3)]
↳ AT Translated Set 2 keyboard id=12 [slave keyboard (3)]
↳ Dell WMI hotkeys id=14 [slave keyboard (3)]
↳ Integrated Webcam id=9 [slave keyboard (3)]
Device ID for my mousepad is 13. Let find out what properties on device 13 are:
user@vn-software:~$ xinput --list-props 13
Device 'ImPS/2 ALPS GlidePoint':
Device Enabled (127): 1
Coordinate Transformation Matrix (129): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
Device Accel Profile (250): 0
Device Accel Constant Deceleration (251): 1.000000
Device Accel Adaptive Deceleration (252): 1.000000
Device Accel Velocity Scaling (253): 10.000000
Evdev Axis Inversion (254): 0, 0
Evdev Axes Swap (256): 0
Axis Labels (257): "Rel X" (137), "Rel Y" (138)
Button Labels (258): "Button Left" (130), "Button Middle" (131), "Button Right" (132), "Button Wheel Up" (133), "Button Wheel Down" (134), "Button Horiz Wheel Left" (135), "Button Horiz Wheel Right" (136)
Evdev Middle Button Emulation (259): 0
Evdev Middle Button Timeout (260): 50
Evdev Wheel Emulation (261): 0
Evdev Wheel Emulation Axes (262): 0, 0, 4, 5
Evdev Wheel Emulation Inertia (263): 10
Evdev Wheel Emulation Timeout (264): 200
Evdev Wheel Emulation Button (265): 4
Evdev Drag Lock Buttons (266): 0
The Device Enabled property for device #13 (Touchpad) is 127 and it set to 1. Let turned it off.
user@vn-software:~$ xinput set-prop 13 127 0
It worked! I loved it.
So, to enable the touchpad, I will using this command "xinput set-prop 13 127 1" on my computer. Please note: The device ID and device enabled property for the touchpad on your computer may not same as mine. You need to find out yours by using commands 'xinput list' and 'xinput --list-props' as describe above.
Updated Aug. 13, 2011: Make sure you check device number by using command "xinput list" before disable your touchpad. Otherwise, you may disable the wrong device.
This discussion "Ubuntu 11.04 with Gnome on Dell 6510: cannot disable touchpad" on UbuntuForums.org offered me a solution. Here, what I did on on my computer:
user@vn-software:~$ xinput list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ Logitech USB Receiver id=10 [slave pointer (2)]
⎜ ↳ Logitech USB Receiver id=11 [slave pointer (2)]
⎜ ↳ ImPS/2 ALPS GlidePoint id=13 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
↳ Video Bus id=6 [slave keyboard (3)]
↳ Power Button id=7 [slave keyboard (3)]
↳ Sleep Button id=8 [slave keyboard (3)]
↳ AT Translated Set 2 keyboard id=12 [slave keyboard (3)]
↳ Dell WMI hotkeys id=14 [slave keyboard (3)]
↳ Integrated Webcam id=9 [slave keyboard (3)]
Device ID for my mousepad is 13. Let find out what properties on device 13 are:
user@vn-software:~$ xinput --list-props 13
Device 'ImPS/2 ALPS GlidePoint':
Device Enabled (127): 1
Coordinate Transformation Matrix (129): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
Device Accel Profile (250): 0
Device Accel Constant Deceleration (251): 1.000000
Device Accel Adaptive Deceleration (252): 1.000000
Device Accel Velocity Scaling (253): 10.000000
Evdev Axis Inversion (254): 0, 0
Evdev Axes Swap (256): 0
Axis Labels (257): "Rel X" (137), "Rel Y" (138)
Button Labels (258): "Button Left" (130), "Button Middle" (131), "Button Right" (132), "Button Wheel Up" (133), "Button Wheel Down" (134), "Button Horiz Wheel Left" (135), "Button Horiz Wheel Right" (136)
Evdev Middle Button Emulation (259): 0
Evdev Middle Button Timeout (260): 50
Evdev Wheel Emulation (261): 0
Evdev Wheel Emulation Axes (262): 0, 0, 4, 5
Evdev Wheel Emulation Inertia (263): 10
Evdev Wheel Emulation Timeout (264): 200
Evdev Wheel Emulation Button (265): 4
Evdev Drag Lock Buttons (266): 0
The Device Enabled property for device #13 (Touchpad) is 127 and it set to 1. Let turned it off.
user@vn-software:~$ xinput set-prop 13 127 0
It worked! I loved it.
So, to enable the touchpad, I will using this command "xinput set-prop 13 127 1" on my computer. Please note: The device ID and device enabled property for the touchpad on your computer may not same as mine. You need to find out yours by using commands 'xinput list' and 'xinput --list-props' as describe above.
Updated Aug. 13, 2011: Make sure you check device number by using command "xinput list" before disable your touchpad. Otherwise, you may disable the wrong device.
Friday, June 10, 2011
Install WordPress 3.1.3 on Ubuntu 11.04
WordPress is web application you can use to create a beautiful blog or website. This is an open source software. You can get it free at http://wordpress.org/download/ . Before you install WordPress on Ubuntu 11.04 (Natty Narwhal), make sure you already install on your Linux machine: Apache, MySQL and PHP (LAMP).
1. Unzip wordpress-3.1.3.zip to a specified.
2. Make the virtual path for Apache web server:
sudo gedit /etc/apache2/httpd.conf
add a new line:
Alias /wordpress /home/yourusername/wordpress
and
restart sudo /etc/init.d/apache2 restart
3. Type http://127.0.0.1/wordpress/readme.html on your browser to read some instruction.
4. Create MySQL database and user for WordPress
mysql -u root -p
mysql> use mysql;
mysql> create database wordpress;
mysql> INSERT INTO user (Host,User,Password) VALUES('localhost','wpuser',PASSWORD('wppass'));
mysql> grant all privileges on wordpress.* to wpuser@localhost;
mysql> flush privileges;
mysql> exit;
5. chmod -c 777 -R ~/wordpress
6. Type http://127.0.0.1/wordpress/wp-admin/install.php to install.
If you got this error message: "Error establishing a database connection", make sure user name and password are correct. It took me almost an hour to figure it out. For some reason, my MySQL password for wpuser@localhost is empty instead of a specified password that I set when I create a MySQL user account.
1. Unzip wordpress-3.1.3.zip to a specified.
2. Make the virtual path for Apache web server:
sudo gedit /etc/apache2/httpd.conf
add a new line:
Alias /wordpress /home/yourusername/wordpress
and
restart sudo /etc/init.d/apache2 restart
3. Type http://127.0.0.1/wordpress/readme.html on your browser to read some instruction.
4. Create MySQL database and user for WordPress
mysql -u root -p
mysql> use mysql;
mysql> create database wordpress;
mysql> INSERT INTO user (Host,User,Password) VALUES('localhost','wpuser',PASSWORD('wppass'));
mysql> grant all privileges on wordpress.* to wpuser@localhost;
mysql> flush privileges;
mysql> exit;
5. chmod -c 777 -R ~/wordpress
6. Type http://127.0.0.1/wordpress/wp-admin/install.php to install.
If you got this error message: "Error establishing a database connection", make sure user name and password are correct. It took me almost an hour to figure it out. For some reason, my MySQL password for wpuser@localhost is empty instead of a specified password that I set when I create a MySQL user account.
Wednesday, June 1, 2011
Running ASP.net on Ubuntu 11.04 using Apache 2 web server
1.1 Install the mod_mono packages:
sudo apt-get install libapache2-mod-mono mono-apache-server2
1.2 Install the mono development tools packages:
sudo apt-get install mono-devel (optional)
2. Enable the Apache module:
sudo a2enmod mod_mono_auto
3. Restart Apache: sudo /etc/init.d/apache2 restart
To test your setup, you can create a test page with the following content anywhere that Apache can see (i.e. /var/www/test.aspx)
References:
https://help.ubuntu.com/community/ModMono
http://www.mono-project.com/Mod_mono
http://ubuntuexperiment.wordpress.com/2009/01/29/running-aspnet-applications-in-ubuntu-using-modmono/
http://thelinuxexperiment.com/uncategorized/setting-up-an-ubuntu-based-asp-net-server-with-mono/
http://www.hbyconsultancy.com/blog/install-asp-net-3-5-environment-for-ubuntu-maverick-10-10.html
sudo apt-get install libapache2-mod-mono mono-apache-server2
1.2 Install the mono development tools packages:
sudo apt-get install mono-devel (optional)
2. Enable the Apache module:
sudo a2enmod mod_mono_auto
3. Restart Apache: sudo /etc/init.d/apache2 restart
To test your setup, you can create a test page with the following content anywhere that Apache can see (i.e. /var/www/test.aspx)
References:
https://help.ubuntu.com/community/ModMono
http://www.mono-project.com/Mod_mono
http://ubuntuexperiment.wordpress.com/2009/01/29/running-aspnet-applications-in-ubuntu-using-modmono/
http://thelinuxexperiment.com/uncategorized/setting-up-an-ubuntu-based-asp-net-server-with-mono/
http://www.hbyconsultancy.com/blog/install-asp-net-3-5-environment-for-ubuntu-maverick-10-10.html
Wednesday, May 4, 2011
How to install thinkorswim Software in Ubuntu 11.04
1. Make sure you have Sun Java Runtime Environment (JRE) or Sun Java Development Kit installed on your machine. If not, using Ubuntu Software Center, search for sun java, to install sun-java6-jre or sun-java6-jdk
2. Download thinkorswim_other_installer.sh
3. Change the thinkorswim_other_installer.sh to execute mode
4. Install to your home folder /home/username/opt/thinkTDA
2. Download thinkorswim_other_installer.sh
3. Change the thinkorswim_other_installer.sh to execute mode
4. Install to your home folder /home/username/opt/thinkTDA
Sunday, March 27, 2011
Git vs Subversion (SVN)
Git and Subversion (SVN) are free and open source version control software. I'm planning to replace Microsoft Visual SourceSafe in Microsoft Windows system. I need a modern open source version control system can use in both platform Linux and Microsoft Windows.
Which one is better?
Which one is better?
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