Powershell reference

http://ss64.com/ps/

Find by file name in Bash

Easy but useful command:
To find a file by name, use 'find' command. It will search all assigned path including its sub-folders

• find 
• 1st argument: the path to find
• -name: file by name
• -i: case insensitive

Bash scripting

Start doing a bit bash scripting now....

this is some thing that fairly simple but took me a few minutes to figure out how...

• You can't use alias by default unless you turn on some kind of options
• to run a variable as a command, there are three commands that you can use
• eval, exec, source 
• Variable should be upper case!

Reload File in Emacs

I can't remember how I deal with this situation.... I just realized that Emacs doesn't reload a file, if it has been modified outside emacs......

To reload a file, this is the command you need to run...M-x revert-buffer

Some simple bash hints

• Command
• ls - list files
• --color=auto: Display files with different colors base on their types
• -C: Display files by column
• set - showing all environment variables
• du - show file size
• -s: summary
• -h: human readable
• cd
• -: go to the previous directory
• history - show command history
• use '!' rerun the command. e.g. !4
• '!!' will run last command
• '!-2' will run the second last command
• use 'export HISTCONTROL=ignoredups' to get rid of duplications
• basename - show the name of a file. (remove directory path)
• can also be used to remove suffixes by add a 2nd argument with the suffixes
• dirname - show the directory of a file 

SQL join basic

In SQL, Join is a powerful and useful operation. It can be used to return data from multiple tables.

There are different types of joins (that I know)

• Inner Join (Default in some DBs): Select only the matched rows from two tables
• Left(Right) Outer Join: select all rows from Left(Right) table and matched rows from the second table
• Cross Join: return all rows from both table. Even there are 'NULL' values in its column

ref: http://en.wikipedia.org/wiki/Join_(SQL)#Natural_join

Setting Up Emacs for Windows

Here is a good .el to help emacs recognize cygwin path style
http://www.emacswiki.org/cgi-bin/wiki/download/cygwin-mount.el

to enable
(require 'cygwin-mount)

(cygwin-mount-activate)

There is a problem with the PS1 variable of bash. Emacs doesn't recognize the escape characters for colours. The solution is to add a condition to the bash profile:

if [ $TERM = emacs] ; then

PS1='\u@\h:\W\n$'

fi

A Useful Emacs 4 Windows documentation

This could help me setting up my emacs in Windows!

ps: Here is how to set the font for Emacs
 M-x set-default-font 
ref: http://www.cs.huji.ac.il/~osigor/emacs/font.html#8

Using quotes in Bash

This is probably incomplete, the quote in bash has the following usage:

• Single Quotes (') -  preserves the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash.
• e.g. echo '\"This Text is writing between two single quotes! $User' will return the original sentence: \"This Text is writing between two single quotes! $User
• Double Quotes (") - preserves the literal value of all characters within the quotes, with the exception of `$', ``', and `\'.
• e.g. echo '\"This Text is writing between two single quotes! $User' will return the sentence: "This Text is writing between two single quotes! Yi

A good Bash scripting tutorial, I need to come back and read it!

A good place where you can get e-books!

Not sure if this is legal. I find this website really useful when I want to learn some new programming stuff.
Download all kind of e-resources for FREE!

Missing the life back in Uni...where I can borrow real books for free.....

New Release!

Not sure exactly how many blogs I have had...Hope I can use this for long...........

The main purpose of this blog is to help me organize my notes and share my ideas, experiences & knowledge with people.

Thanks for reading this.

Have fun...