Usage of cat command

cat command functionality:
1. create
2. view
3. join files

cat is short for catenate (to join things together, end-to-end)
- Create file
cat > file1
 enter text
 more text
# press Enter, CTRL-d to exit

- View file(s)
cat -n filename # will number all lines
cat -b filename # will number all non-blank lines

cat -t filename # all tabs to be shown as ^I
cat -s filename # remove extra blank lines. 1 blank line is allowed.
cat -A filename # combine -t & -s options together

- Join Files
cat test1 test2 # join both files and show output in stdout
cat test1 test2 > test # Join both files and add to stdout

Bash Shortcuts

GNU Readline Library enable to edit the command line shortcuts. Readline uses emacs key binding. It means a lot of CTRL/ALT keys.

Ctrl+C # Interrupt to exit, terminate the command
Ctrl+D # disconnect from shell
Ctrl+Z # suspend the process, suspend/stop the command
Ctrl+l # clear screen
Ctrl+s # stops the output to the screen
Ctrl+q # allow output to the screen
(If previously stopped using Ctrl+s)
!! - run last command
Ctrl+r # search the history backwards
Ctrl+g # escape from history searching mode
Ctrl+a # go to start of the command line
Ctrl+e # go to end of the command line
Ctrl+f # move forward one character (identical to VIM)
Ctrl+b # move backward one character (identical to VIM)
Ctrl+p # previous command in history
Ctrl+n # next command in history

kill processes that match grep pattern

I open about 20 copies of the same file. I used the command below to kill them.
kill -9 `ps auwwwx | grep "vim /tmp/continuous_migration.log" | awk '{print $2}' | xargs

diff

diff from_file to_file
diff from_dir to_dir

diff useful lags
-B (Ignore changes whose lines are all blank.)
-b (Ignore changes in the amount of white space)
-y (side by side ouput comparison)

useful alias:
diff -Bb alias

Changing Linux Login Shell

Ways to change Linux shell
1. chsh (change login shell)
2. edit /etc/password
3. exec in .login file

how to delete file which name start with minus sign?

rm "./-filename"

Defiance movie

My sister recommend the movie. She watched during her flight from Israel. Great movie.
Very sensitive. It remind my grandparents story about world word two. They had very difficult life and survived Nazi occupation of former Soviet Union. A lot of members of my parents dies during the war. My father uncle was killed in Latvia in 1944 as a soldier. My father grandfather was killed in Ghetto in 1943...
Most of the jewish familes have similar story to Bielski brothers'.

I purchased the movie in Amazon Instant Video. For more information about the movie, here is link on Wikipedia

Also, 15 years ago my grandmother Klara died. She was only 67 years old...