CTM 3G modem settings in OSX

Just arrived in Macau. Friend passed me his CTM (a mobile service provider I reckoned) 3G dongle to use during my stay. Googled around and found the correct APN + username + password settings.

Telephone Number: *99#
Account Name: guest
Password: guest

Under "Advanced", use

Vendor: Generic
Model: GPRS (GSM/3G)
APN: ctm-mobile

Diffing tables in Cucumber


Then /^I should see the following within "([^"]*)" area:$/ do |selector, table|
actual_table = tableish("table#{selector} tr", "td,th" ).to_a
table.diff!(actual_table)
end


references:
https://github.com/aslakhellesoy/cucumber/wiki/multiline-step-arguments
http://railscasts.com/episodes/186-pickle-with-cucumber

Making my Textmate better

Install cucumber bundle

https://github.com/papercavalier/cucumber-tmbundle

Install rspec bundle

https://github.com/rspec/rspec-tmbundle

RVM Textmate integration

http://rvm.beginrescueend.com/integration/textmate/

Transition to HTML using HTML5 tags as CSS classes

So instead of

...

Use

...

Difference between l10n & i18n

On Wed, Mar 29, 2000 at 11:39:22PM +0200, Antonio Larrosa wrote:
> David Faure wrote:
> >
> > > Hi,
> > >
> > > I just wondered why the directories are called i10n in
> > > kdebase, and what the difference to i18n is....
> >
> > l10n = localization (country-specific settings such as how to represent
> > numbers, dates, money, ...)
> > i18n = internationalization (translations)
>
> Btw, does anybody knows why are they called with those names ?
> I've been wondering for a long time :-)

Hehe, yes.
Count the number of letters between the starting and the ending
letter, in both words ;-)

referece: http://lists.kde.org/?l=kde-devel&m=95436660012782&w=2

Debugging: Show the webpage after a cucumber step


# Example
#
Scenario: Signing in
When I go to the home page
And I fill in "username" with "john"
And I fill in "password" with "john"
Then show me the page

# Actual implementation
# Uses webrat's method
#
Then /^show me the page$/ do
save_and_open_page
end


Suppress NOTICE messages from Postgresql when running rake cucumber


# Notice messages spewed
#
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index ...

# Fix
# Add to database config in config/database.yml
#
test:
...
min_messages: WARNING;;


Stop rvm from complaining about world writable /usr/local/bin

# Error message
#
/Users/velvetpd/.rvm/gems/ruby-1.9.2-p0@babylon/gems/bundler-1.0.7/lib/bundler.rb:199: warning: Insecure world writable dir /usr/local in PATH, mode 040777

# Fix
# This was probably caused by instructions to install Homebrew
# http://objectliteral.blogspot.com/2010/12/installing-homebrew-on-osx.html
#
chmod o-w /usr/local/bin
chmod o-w /usr/local

Git completion for git installed via Homebrew in OSX


# In .bashrc

if [[ -s "/usr/local/Cellar/git/1.7.3.3/etc/bash_completion.d/git-completion.bash" ]]; then
source "/usr/local/Cellar/git/1.7.3.3/etc/bash_completion.d/git-completion.bash"
fi



get forward (alt-f) and backward (alt-b) word working in OSX terminal

Under "Preferences > Keyboard" check "Use Option as Meta key"

Installing Nokogiri on CentOS


sudo yum install -y libxml2 libxml2-devel libxslt libxslt-devel
sudo gem install nokogiri


Installing postgresql on CentOS


sudo yum install postgresql postgresql-devel postgresql-server

mkdir /usr/local/pgsql/data
chown postgres /usr/local/pgsql/data

sudo su
su postgres

/usr/bin/initdb -D /usr/local/pgsql/data

createuser OR
psql -c "create role ROLE with superuser"


Installing rvm on CentOS


sudo yum install git
bash < <( curl http://rvm.beginrescueend.com/releases/rvm-install-head ) # issue "rvm notes" and follow instructions on dependencies

Install postgresql using homebrew on OSX

If there's existing postgres install,

brew rm postgresql --force

Else

brew update
brew install postgres

Then follow instructions on printed by homebrew

initdb /usr/local/var/postgres
cp /usr/local/Cellar/postgresql/9.1.4/homebrew.mxcl.postgresql.plist ~/Library/LaunchAgents/
launchctl load -w ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start

Installing rvm on OSX


brew install readline
brew install most
sudo gem install rvm #install rvm
rvm-install
rvm install 1.8.7 -C --enable-shared,--with-readline-dir=/usr/local
rvm install 1.9.1 -C --enable-shared,--with-readline-dir=/usr/local
rvm install 1.9.2 -C --enable-shared,--with-readline-dir=/usr/local
rvm 1.8.7 --default


reference: http://www.blog.bridgeutopiaweb.com/post/how-to-install-rvm-and-rails-3-on-snow-leopard/

Installing Homebrew on OSX


sudo chown -R $USER:staff /usr/local

curl -Lsf http://github.com/mxcl/homebrew/tarball/master | tar xvz -C/usr/local --strip 1

brew install git

git clone http://github.com/mxcl/homebrew.git /tmp/homebrew
mv /tmp/homebrew/.git /usr/local/
rm -rf /tmp/homebrew


references: http://userprimary.net/posts/2010/08/19/installing-homebrew-for-OSX/

Difference between staff and wheel groups in OSX

User admin belongs to "staff" group while User root (the only one) belongs "wheel" group.

reference: http://superuser.com/questions/20420/difference-between-default-groups-on-mac-osx

List groups in osx


more /etc/group


Using gnome-mplayer to play embedded mpeg videos in Firefox


sudo apt-get install gnome-mplayer mozilla-mplayer

# Remember right click on the video in Firefox and configure video output to be X11.



Upgrading my Samsung Galaxy S to Froyo

I went through the ordeal of installing Samsung Kies, their mobile/player manager and getting it to recognize my phone, only to find out that the custom firmware on my phone installed during a visit to Samsung Service Center couldn't offer an upgrade through Kies.

But thanks to the wonderful internet, there're other ways to flash the ROM to the latest and greatest. The links below provide a very clear step by step instructions.

Flashing to Froyo:
http://touristinparadise.blogspot.com/2010/11/samsung-galaxy-s-how-to-install-froyo.html

Upgrading Kernel for lagfix:
http://touristinparadise.blogspot.com/2010/11/samsung-galaxy-s-how-to-install.html

Finding source location for a rail method


# Eg. if you want to find source location for DateTime.tomorrow

irb(main):001:0> DateTime.method(:tomorrow).source_location


Network manager in Ubuntu 10.10

Not sure which version of Ubuntu has this been implemented.


# Previously

sudo etc/init.d/NetworkManager stop

# Updated

sudo etc/init.d/network-manager stop


Enabling bash completion

Uncomment the following in /etc/bash.bashrc


if [ -f /etc/bash_completion ]; then
. /etc/bash_completion
f


Hijacked keyboard shortcut

Somehow when I upgraded to Ubuntu 10.10, my "Shift + f" launches firefox.

Apparently that keybinding was assigned to run command_1 in metacity which was assigned to launch firefox. To disable it go to,

gconf > apps > metacity > global_keybindings

How to find hard disk partition of your ubuntu in terminal


df -h


Error messages for Rails 3

# Deprecated

<%= error_messages_for :question %>

# Use partial in app/views/shared

<% if target.errors.any? %>  
<%= pluralize(target.errors.count, "error") %> prohibited this record from being saved:
<% target.errors.full_messages.each do |msg| %>
<%= msg %>
<% end %>     
<% end %> 

# Render partial in view

<%= render "shared/error_messages", :target => @question %>

17 Don'ts Of Mobile Application Design Development

Don’t...

... assume a need
... go chasing waterfall
... be short-sighted
... assume browsers are equal
... trivialize choice of platform
... downplay user experience
... gloss over bits & bytes
... be online only
... favour branding over users
... disrupt the experience
... load too much too fast
... squeeze the world in
... re-invent the wheel
... make user type
... do roll-overs
... forget to test
... forget to guide your users

reference: http://www.slideshare.net/ronnieliew/mobile-application-design-development-5465097

Compressing a PDF file

To compress a PDF file:

Open Preview, in your Applications folder.


Choose File > Open, select the PDF file to compress, and then click Open.


Choose File > Save As, choose Reduce File Size from the Quartz Filter pop-up menu, and choose a name and location for the new PDF file.


Click Save.

Kill applications using killall in Mac OSX Terminal

# This doesn't kill the processes

killall "Google Chrome"

# Need to append with sudo

sudo killall "Google Chrome"

Sorting searchlogic results

params[:filter][:order] = "ascend_by_created_at"
@search = Note.search(params[:filter])
@notes = @search.all

URL encoding

Reference: http://www.blooberry.com/indexdot/html/topics/urlencoding.htm

ASCII Control characters
	Why:	These characters are not printable.
	Characters:	Includes the ISO-8859-1 (ISO-Latin) character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal.)

Non-ASCII characters
	Why:	These are by definition not legal in URLs since they are not in the ASCII set.
	Characters:	Includes the entire "top half" of the ISO-Latin set 80-FF hex (128-255 decimal.)

"Reserved characters"
	Why:	URLs use some characters for special use in defining their syntax. When these characters are not used in their special role inside a URL, they need to be encoded.
	Characters:	Character Code Points (Hex) Code Points (Dec)  Dollar ("$")  Ampersand ("&")  Plus ("+")  Comma (",")  Forward slash/Virgule ("/")  Colon (":")  Semi-colon (";")  Equals ("=")  Question mark ("?")  'At' symbol ("@") 24 26 2B 2C 2F 3A 3B 3D 3F 40 36 38 43 44 47 58 59 61 63 64

"Unsafe characters"
	Why:	Some characters present the possibility of being misunderstood within URLs for various reasons. These characters should also always be encoded.
	Characters:	Character Code Points (Hex) Code Points (Dec) Why encode? Space 20 32 Significant sequences of spaces may be lost in some uses (especially multiple spaces) Quotation marks 'Less Than' symbol ("<") 'Greater Than' symbol (">") 22 3C 3E 34 60 62 These characters are often used to delimit URLs in plain text. 'Pound' character ("#") 23 35 This is used in URLs to indicate where a fragment identifier (bookmarks/anchors in HTML) begins. Percent character ("%") 25 37 This is used to URL encode/escape other characters, so it should itself also be encoded. Misc. characters:    Left Curly Brace ("{")    Right Curly Brace ("}")    Vertical Bar/Pipe ("|")    Backslash ("\")    Caret ("^")    Tilde ("~")    Left Square Bracket ("[")    Right Square Bracket ("]")    Grave Accent ("`") 7B 7D 7C 5C 5E 7E 5B 5D 60 123 125 124 92 94 126 91 93 96 Some systems can possibly modify these characters.

Random select ruby array elements

[horse, donkey, mule][rand(3)]

Functional test for respond_to :json in Rails

# Notes controller

def index
...
  respond_to do |format|
    format.json { render :json => @notes }
  end
end

# Notes functional test

params = {:format => 'json', :title => ...}

get :index, params

notes = JSON.parse(@response.body)
assert_equal note.title, notes[0]['note']['title']

Renaming file extensions in Mac OSX

Downloaded a .zip file and tried renaming it to .apk but OSX keeps recognizing as a zip file...

Apparently Mac tries to be smart in knowing the original file type so to really change the file type, you gotta right click select "Get info" and rename it from there. There'll be a prompt warning you about the type of application associated with the new file extension.

Fix for Samsung Galaxy S terrible lagginess

Fresh out of the box the Samsung Galaxy S sped like a rocket but after a week of usage it began to lag TERRIBLY. Killing apps or rebooting phone doesn't help. Googling the issue reveals its a known bug in the way the phone does I/O with its internal SD card.

Here's a fix by Tayutama at xda-developers.com. I've edited the instructions to be more accurate after trying it out myself.

Reference: http://forum.xda-developers.com/showpost.php?p=7587405

1. The update.zip installs all the files needed. It is attached here; http://forum.xda-developers.com/attachment.php?attachmentid=377244&d=1281437129
2. Place it in the top folder on your internal sdcard, ie. /sdcard
3. Turn off your phone.
4. Hold down Up(Volume) + Power Button + Menu button(Home button) simultaneously for a couple of seconds until u see the manual boot screen.
5. Use the up and down buttons to get to update.zip.
6. Press menu button on update.zip to select it
7. It installs root, correct busybox (1.17.1), superuser.app, as well as all the scripts needed for the fix and the 'MCR Scripts' app to run the scripts.
8. After install, the phone restarts.
9. Go to the newly installed 'MCR Scripts' application from the app list, open it and choose from 3 scripts. For example, Lagfix10024 is the 1gb ex2 version.
10. The script would launch superuser permission prompt. Click "Allow" and it should run in a terminal for about 10 minutes. Don't worry if it seems to get stuck on "...takes a while...". You'll see some output of what it's doing later.
11. You should see an 'All complete' terminal prompt, and this means you can close the application.
12. Run Quadrant app (install from Market) to test if the fix was applied. You should see results like in http://www.droiddog.com/android-blog/2010/08/galaxy-s-lag-fix-makes-phones-fly/

**PLEASE READ!!! Some hiccups that I've encountered.**

The first time I clicked "Allow" in step 10, the script encountered Permission denied and didn't do anything. I had to stop the script and try it another time before it got going.

Before 'All complete' prompt, the script seemed to have repeated what it needed to do. After "installing" my Market app couldn't work. Rebooting phone caused screen to be blank. I had to press Up + Menu + Power to enter manual boot and do Factory reset. That meant losing data on my phone. At least I didn't have anything important irrecoverable as my Contacts are synced with Gmail Contacts. I installed and ran Quadrant just to see if the fix had been applied and saw that benchmark results were that of before fix.

I tried again by repeating from step 3. This time the script seemed to have executed properly. I ran Quadrant again and got the benchmark results. Running applications did seem MUCH FASTER but I hope it's not because I've factory reset the phone...

Lithium ion batteries first charge

According to an article at http://www.batteryuniversity.com/print-partone-12.htm

Unlike nickel and lead-based batteries, a new lithium-ion pack does not need cycling through charging and discharging. Priming will make little difference because the maximum capacity of lithium-ion is available right from the beginning. Neither does a full discharge improve the capacity of a faded pack.

So really the "full discharge and initial charge of 8 hours" were obsolete practices of the Nickel Cadmium batteries era.

Remapping keyboard keys in Mac OSX

Use KeyRemap4MacBook to remap keys on your OSX keyboard.

Snow Leopard Only:
http://pqrs.org/macosx/keyremap4macbook/files/KeyRemap4MacBook-6.7.0.pkg.zip

It'll enable "FN + Numpad" by default. What I would really like is a way to do "Left/Up/Down/Right" without using the arrow cursor which forces my hand to shift down the keyboard too much. The utility provides a "Vi Mode" where you can map "FN + hjkl" for Left/Up/Down/Right.

To change CapsLock to Escape you need to download another utility from the website.

Snow Leopard Only:
http://pqrs.org/macosx/keyremap4macbook/files/PCKeyboardHack-6.3.0.pkg.zip

Tunnel Firefox connections through a server

Use openSSH to open up SOCK5 tunneling to server

ssh -fND PORT_NO USERNAME@IP_ADDRESS

Configure network connection in Firefox to use manual proxy. Leave everything blank except

SOCKS Hosts: localhost Port: PORT_NO

Controling a Mac OSX using VNC

From "System Preferences > Sharing > Screen Sharing", click "Computer Options" and set password and voila!

reference: http://lifehacker.com/319528/remote-control-leopard-with-tightvnc

Using curl to post data to a rails app

curl -X POST -d "location[lat]=111&location[lng]=222" http://localhost:3000/users/123/devices/456/locations

However rails require authenticity token. To overcome that just turn forgery protection off.

# config/environment.rb
config.action_controller.allow_forgery_protection = false

Print screen in Mac OSX

Fullscreen:

- Hold down Apple key ⌘ + Shift + 3 and release all
- Mouse click on screen

Portion of screen:

- Hold down Apple key ⌘ + Shift + 4 and release all key
- Drag mouse to select portion of screen to capture

From http://www.techiecorner.com/138/how-to-do-print-screen-in-mac-os-x/

Untrack file in git

git rm --cached FILENAME

Blank screen after resuming from suspend in Ubuntu

Of late I'm getting blank screen from suspend on my Ubuntu netbook after starting to use a second external monitor. Not sure the reason why but the fix for me is to hit "CTRL + ALT + F7".

X11 error: BadAlloc (insufficient resources for operation) while using mplayer

mplayer -vo x11 PATH_TO_FILE

Use mplayer to play stuttering web flash videos on browsers (high CPU load)

Playing web flash videos on my Ubuntu Firefox can yield super high CPU load as flash is poorly supported on Linux. Couple that with a sub-optimal Firefox Flashplayer plugin which causes CPU load to spike up to almost 100% and this makes the video stutter like mad.

One solution is to start and pause the video to initiate caching and use mplayer to play the cached flash video instead.

mplayer /tmp/Flash*

Now it plays smooth. Fullscreen? No problem. Just toggle "F" on your keyboard!

Share iTunes playlist and files over network using Ubuntu as fileserver

# Install mt-daapd
sudo apt-get install mt-daapd

# Edit mt-daapd.conf and specify media folder
sudo vi /etc/mt-daapd.conf

# Restart mt-daapd
sudo /etc/init.d/mt-daapd stop
sudo /etc/init.d/mt-daapd start

# Configurations can be done on webpage
# Remember to port forward 3689 to ubuntu machine
http://localhost:3689

Undo git add

git reset HEAD PATH_TO_FILE

"No more PTYs. Sorry, could not find a PTY" error in GNU Screen

It's a /dev/ptmx file permission problem.

chmod a+w /dev/ptmx

No root user created for mysql in Ubuntu Hardy

/etc/init.d/mysql stop
mysqld --skip-grant-tables &
mysql -u root mysql
mysql> INSERT INTO user VALUES ('localhost','root',password('newpassword'),'Y','Y ','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y', 'Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','' ,'','','',0,0,0,0); 

Turning on ALT keys in Mac OS X Terminal

Under Terminal "Preferences", make sure to check the ""Use options as meta key" in the "Keyboard" tab

Installing Hamachi on Mac OS X Snow Leopard

reference: http://www.command-tab.com/2008/08/29/how-to-run-hamachi-on-leopard/

Remember to download and install Tun/Tap package!

http://tuntaposx.sourceforge.net/

After that just download and install hamachi for Mac OS X

https://secure.logmein.com/products/hamachi/list.asp

cd /Users/you/Downloads/hamachi-0.9.9.9-20-osx
sudo ./install
hamachi-init
sudo /usr/sbin/tuncfg
hamachi start
hamachi login
hamachi join NETWORK
hamachi go-online NETWORK

Cannot pair up newly bought Aztech 109E with existing Aztech 110E + 110EW pair.

Aztech Homeplug models 108*, 109*, 110*, ie. 200mbps series, are supposed to be able to work with each other. Had trouble pairing up newly acquired Aztech 109E with already existing 110E* pair.

The solution was to reset the Private Network Name that the existing pair was using. This can be done by simply pressing the "Simple Connect" button for ALL the pairs for 10secs.

'BadAlloc (insufficient resources for operation)' errror message while playing mp4 using mplayer

Fixed this by specifying video driver as such

mplayer -vo x11 PATH_TO_VIDEO

Selecting GNU screen profile in Ubuntu Lucid Lynx

screen is now managed by byobu package

byobu-select-profile

Streaming radio using mplayer

mplayer -playlist RADIO_STREAM_URL

Finding uninvoiced fees in rails

# Models

Class InvoiceItem < ActiveRecord::Base
  belongs_to :fee
end

Class Fee < ActiveRecord::Base
  has_one :invoice_item
end

# Namedcope in Fee model

namedscope :uninvoiced, {
  :conditions => "fees.id NOT IN (SELECT fee_id FROM invoice_items)"
}

Find ubuntu release and version on the command line

lsb_release

or 

cat /etc/lsb-release

Configure git colors and output format

# Add color
git config color.ui auto

# Format for log, whatschanged
git log --pretty=

Installing OSQA

While installing OSQA, an opensource clone of StackExchange (Stackoverflow) written in Python (Django), I encountered a few gotchas

Installation instructions:
http://wiki.osqa.net/display/docs/OSQA+Installation+and+Upgrade+Guides
http://wiki.osqa.net/display/docs/Setting+Up+OSQA+for+Apache
http://wiki.osqa.net/display/docs/Ubuntu+9+with+MySQL

Gotchas:

1. Install mod-wsgi for Apache2

sudo apt-get install libapache2-mod-wsgi

2. Commented code in Apache.conf

The following commented code seems to screw up restarting of apache

WSGISocketPrefix /path/to/socket/sock #must be readable and writable by apache
WSGIPythonHome /usr/local #must be readable by apache
WSGIPythonEggs /var/python/eggs #must be readable and writable by apache

Just get rid of them.

3. WSGI script in documentation

As documented in http://wiki.osqa.net/display/docs/Setting+Up+OSQA+for+Apache

os.environ['DJANGO_SETTINGS_MODULE'|'DJANGO_SETTINGS_MODULE'] = 'osqa.settings'

That pipe screws things up. I'm not exactly familar with python so maybe it's deprecated in Python 2.6? Anyways just get rid of it.

os.environ['DJANGO_SETTINGS_MODULE'] = 'osqa.settings'

4. Table migration

Apparently if you followed the recommendation to use South for migration you'll soon find that it FAILS. Yikes! Search their Q&A (meta) provides an answer.

http://meta.osqa.net/question/111/installation-programmingerror-forum_keyvalue-doesnt-exist

Just do

./manage.py syncdb --all
./manage.py migrate --fake

Hmm...

Recover deleted branches in Git

Accidentally deleted a branch? No problem. Git reflog to the rescue.

git checkout -b recover_lost_commits

git reflog

e9c17db... HEAD@{0}: checkout: moving from stable to master
e9c17db... HEAD@{1}: checkout: moving from stable to e9c17dbfffd79f2bf30530e144c43c0f47322826^0
318c0f2... HEAD@{2}: checkout: moving from master to stable
e9c17db... HEAD@{3}: commit: Forgot to add images to CSS and adjusted positions.
3baab51... HEAD@{4}: commit: Added new buttons.

git merge e9c17db

Awesomeness.

Using minitest for speedier unit tests

sudo gem install minitest # Install MiniTest
sudo gem install minitest_tu_shim # Install Test::Unit shim
sudo use_minitest yes

GOTCHA

If you've freezed rails into a project then trying to script/server will throw the following error.

.../vendor/rails/activesupport/lib/active_support/dependencies.rb:445:in `load_missing_constant': uninitialized constant Test (NameError)

Finding and killing application processes in the command prompt on Windows XP

To find PID or process name

tasklist.exe

Note: Not available in Windows XP Home edition by default. Google and download it.

To kill the PID or process name, look for tskill.exe under c:\windows\system32\

tskill.exe PID | PROCESS NAME

HP F2410 printer on Ubuntu

Wanted a printer that works on Ubuntu. Did some research and realized HP printers are the most well supported.

https://wiki.ubuntu.com/HardwareSupportComponentsPrinters

Acquired a cheap SGD99.00 HP F2410 printer off local store. Installing it isn't as easy as plug and play but it's close enough. Essentially CUPS doesn't have the right PPD so it's off to HP website to download the the driver. They even provide a neat installation run file that does dependency checks!

http://hplipopensource.com/hplip-web/downloads.html

Printing well and scanning works with Xsane. At such a low price I can't be happier. I owe HP one!

Play remote media files over ssh using mplayer

ssh username@192.168.1.60 "cat ~/Video/apprentice.avi" | mplayer -

Set Ubuntu to use Google DNS for internet

Sometimes my 2Wire router doesn't seem to route to the DNS properly. As such I can ping IP addresses but not domain names. To fix that just tell Ubuntu to use Google DNS (or any other free DNS service) directly.

# In /etc/dhcp3/dhclient.conf

prepend domain-name-servers 8.8.8.8, 8.8.4.4;

Sync music/podcasts to mobile phone

Essentially use rsync to sync folders between multiple machines which in this case the host machine with the music files and the mobile phone storage.

rsync ~/Music /media/disk/Music -rP

For podcasts it'll be a good idea to use cronjob to download new podcasts. I'm using a remote server to download them.

# On my remote server

sudo apt-get install podget

# crontab -e on server
0 * * * * /usr/bin/podget -s

# On my local host machine with mobile phone plugged in

rsync username@remote-server:./Music/Podcasts /media/disk/Podcasts -rP

Stop restart popup after automatic updates in Windows XP

Absolutely annoying feature of windows is a popup that keeps asking you to restart the system after a Windows update. Disable that!

# Disable current popup from the command prompt

net stop "automatic updates"

# Disable future auto restarting of system. 
# I'm using Windows XP Home so can't access gpedit.msc. 
# Need to use a registry script instead --> stop_update_restart.reg
# P.S. note the first line.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU]
"RebootRelaunchTimeoutEnabled"=dword:00000000
"NoAutoRebootWithLoggedOnUsers"=dword:00000001

Full path of file in ruby

File.expand_path(__FILE__)

cp with progress indicator by using rsync instead

# Instead of

cp -r folder destination_folder

# Use rsync instead

rsync folder destination_folder -P

Comparing 2 files using diff

diff -uN app/models/common_test.rb app/models/major_test.rb  | vi -

Running ruby scripts as cron jobs in rvm environment

# This will fail to run properly

*/5 * * * * /usr/bin/env ruby /home/username/twitter.rb

# Need to run the script in full bash environment

*/5 * * * * bash -c 'source /home/username/.rvm/scripts/rvm && /usr/bin/env ruby /home/username/twitter.rb'

Cron log in Ubuntu

* Edit /etc/syslog.conf and uncomment the line starting with cron.*
* touch /var/log/cron.log
* Run /etc/init.d/rsyslog restart
* Run /etc/init.d/cron restart

Changing of syslog.conf location in Ubuntu Karmic

Old:

/etc/syslog.conf

New:

/etc/rsyslog.d/50-default

Changing timezone in terminal

sudo dpkg-reconfigure tzdata

Rvm notes

Getting prepared

sudo apt-get update
sudo apt-get -y install build-essential zlib1g zlib1g-dev libxml2 libxml2-dev libxslt-dev sqlite3 libsqlite3-dev locate git-core libssl-dev openssl autoconf subversion bison
sudo apt-get -y install curl wget

For Ubuntu, use rvm package to download and complie zlib

rvm package install zlib
rvm remove 1.8.7
rvm install 1.8.7 -C --with-zlib-dir=$rvm_path/usr

Before installing any versions of ruby using rvm

sudo apt-get install libssl-dev

Installing Ruby Enterprise Edition

Error running './installer -a /home/username/.rvm/rubies/ree-1.8.7-2010.01  --dont-install-useful-gems ', please check /home/username/.rvm/log/ree-1.8.7-2010.01/install*.log
There has been an error while trying to run the ree installer. Aborting the installation.

# Need to install the following library first
sudo apt-get install libreadline5-dev
rvm install ree

Rails 3 notes

JQuery:

Grab the jQuery driver at http://github.com/rails/jquery-ujs and put it in your javascripts directory. Include the file in the layout.

http://joshhuckabee.com/jquery-rails-3

Forms:

Rails requires an authenticity token to do form posts back to the server. This helps protect your site against CSRF attacks. In order to handle this requirement the driver looks for two meta tags that must be defined in your page's head.

csrf_meta_tag

Routing:

Old

link_to :controller => 'user_sessions', :action => 'destroy'

New

# Route
match '/log' => "user_sessions#destroy", :as => :logout

# View
link_to 'Logout', '/logout'

Vim can't make backup file

Ensure that the backup directory in .vimrc exists.

# in .vimrc

set backup
set backupdir=~/.vim/backups

mkdir -p .vim/backups

Vim unable to open swap file

If you see the following message when opening a vim file

Unable to open swap file for "{filename}", recovery impossible

The directory specified in your vim for swap files is missing. In my case it's ~/.vim/tmp.

# in .vimrc
set directory=~/.vim/tmp

mkdir -p ~/.vim/tmp

Git diff changes staged

# On branch master
# Changes to be committed:
#   (use "git reset HEAD ..." to unstage)
#
#       modified:   app/views/matriculations/new.html.erb

To see changes,

git diff --cached (pre-1.6)
git diff --staged

Rails, RedCloth, textilize gotcha

# This doesn't work! It returns html in pure strings and not the html elements!

textilize @blog.content

# Need this extra step.

sanitize(textilize @blog.content)

**UPDATED**

The problem lies that Rails 3 ERB uses h() helper by default

<\%= xxx %>
<\%= h(xxx) %>

To get past this use context_tag() or raw()

xxx = content_tag(:p, "blah")
<\%= xxx %>

xxx = "<\p>blah<\/p>"
<\%= raw xxx %>

Using Fn triggered blue numpad keys for navigation on your laptop

Laptop keys are usually cramped and accessing the usual arrow and page keys are a hassle. I find it useful to use the "numpad" triggered by Fn key.

Fn + 7 = Home
Fn + 1 = End
Fn + 9 = Pg Up
Fn + 3 = Pg Down
Fn + 8 = Up
Fn + 2 = Down
Fn + 4 = Left
Fn + 6 = Right

Bringing jobs into background in terminal

# Suspend job
CTRL + z

# View jobs
jobs

# Bring job into background
%1 &

# Bring job into foreground
%1

Open files at line number in Vim

:e PATH_TO_FILE:LINE_NO

Eg.
:e app/models/user.rb:10

Command line calculator

bc -l

Installing Flash & Java on Firefox & Chromium browsers

1. Install Flash & Java
2. Symlink executables to browser plugin folder

Java

sudo ln -s  JAVA_PLUGIN_PATH BROWSER_PLUGIN_PATH

Flash

sudo ln -s FLASH_PLUGIN_PATH BROWSER_PLUGIN_PATH

To find JAVA_PLUGIN_PATH

locate libnpjp2.so
/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/i386/libnpjp2.so

To find FLASH_PLUGIN_PATH

locate libflashplayer.so
/usr/lib/flashplugin-installer/libflashplayer.so

And BROWSER_PLUGIN_PATH is

# Firefox 
/usr/lib/mozilla/plugin/

# Chromium 
/usr/lib/chromium/plugin/

#Google-Chrome 
/opt/google/chrome/plugin/

NOTE: symlinks must be updated after every java upgrade

Factory Girl has many associations gotcha

Suppose Post has many Items

class Post < ActiveRecord::Base
  has_many :items
end

class Item < ActiveRecord::Base
  belongs_to :post
end

When setting up data for tests using factory girl

Factory.define :item do
  u.post {|p| p.association(:post)}
end

Don't do this!

@post.items << Factory(:item)

Factory will create an item with another post_id and this will not be automatically changed to @post.id. Instead do this.

Factory(:item, :post => @post)

Undo last Git commit with last commited files for edit

git reset --soft HEAD^
git reset

Running Shoulda & Factory Girl in Rails 3

Rails 3 uses Bundler gem to handle gem dependencies. Encountered some problems with Shoulda and Factory Girl.

# Gemfile

group :test do
  gem "shoulda"
  gem "factory_girl"
end

Shoulda and Factory Girl macros are not loaded so I had to require the gems in test/test_helper.rb

# test/test_helper.rb

require 'shoulda'
require 'factory_girl'
Factory.definition_file_paths = [ File.join(Rails.root, 'test', 'factories') ]
Factory.find_definitions

Problem installing sqlite3-ruby gem

Never learnt my lessons. Encountered this so many times.

sudo gem install sqlite3-ruby

Building native extensions.  This could take a while...
ERROR:  Error installing sqlite3-ruby:
        ERROR: Failed to build gem native extension.

/usr/bin/ruby1.8 extconf.rb
checking for fdatasync() in -lrt... yes
checking for sqlite3.h... no
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

The solution is to make sure the following library's installed!

sudo apt-get install libsqlite3-dev

Review git commits in terminal

git log -u HEAD^..HEAD

Play asx streams with mplayer

mplayer -playlist URL

# if steams gets choppy

mplayer -playlist URL -ao sdl

rake cucumber:tags in verbose mode

rake cucumber:ok CUCUMBER_OPTS="--verbose"

rake test:units with verbose output

rake test:units TESTOPTS="-v"

View git object tree in terminal

git log --graph --oneline --all

SHOUTcast on Ubuntu

sudo apt-get install tunapie

Download file from Linux machine to Windows machine using SCP

- Download PSCP.exe (http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html)
- Open up Command Prompt
- Type the following

# Eg. if my pscp.exe is on my Windows desktop

"C:\Documents and Settings\Jason\Desktop\pscp.exe" jasonong@IP_ADDRESS_OF_LINUX_MACHINE:./PATH/TO/FILE "c:\Temp"

Count number of files in directory

find files | count lines

find . -type f | wc -l

Reset Gnome keyring password

rm .gnome/keyrings/login.keyrings
rm .gnome/keyrings/default.keyrings

X Forwarding in Windows

XMing + Putty

- XMing & launch XLaunch
- Launch Putty, making sure that "SSH" > "Enable X11 forwarding" is checked and "MIT-Selected-Cookie-1" is selected.

Connect linux and windows machine via hamachi vpn gotcha

Make sure window's firewall is off...

Default image viewer on ubuntu

# Eog is the default image viewer in Ubuntu

eog image.jpg

Launch applications with X display in remote machine

DISPLAY:0 application executable

Eg.

DISPLAY:0 gnome-terminal
DISPLAY:0 rake selenium:rc:start