Linux Misc. Commands

Complete Command in Editor : Ctrl + X + E
Set Default Editor : $EDITOR

Open a file in its default application : xdg-open

Cycle through the last part of each command : Alt + .
Fetches the value of !$ of each command

Redirect Errors to Output File : ls -lah file.txt not-here > output.txt 2>&1

Read input from user till EOF not reached : cat << EOF > <filename>

Locate Command uses an database to find files quickly on the system
On most systems this files is updated automatically once daily (Using cron task)
Manually update DB : sudo updatedb

The -- operator is used as argument separator
cd -- -foo : Change directory to -foo folder (Without the argument separator -foo would have been interpreted as -f -o -o)

Fork Bomb

:(){ :|: & };:

NOTE

• sudoedit /etc/security/limits.conf (Set Limits)
• This restriction does not work on the root user

Build Package Dependencies

sudo apt install -y pkg-config \
libcups2-dev libsmbclient-dev \
libcairo2-dev libjpeg-dev libgif-dev \
libmariadbclient-dev default-libmysqlclient-dev \
libpcap-dev libcurl4-openssl-dev libssl-dev \
libtool libsqlite3-dev build-essential libgtk-3-dev \
checkinstall libreadline-dev libncursesw5-dev libssl-dev \
tk-dev libgdbm-dev libc6-dev libbz2-dev \
libnetfilter-queue-dev libnfnetlink-dev \
libncurses-dev gawk flex bison openssl dkms \
libelf-dev libudev-dev libpci-dev libiberty-dev autoconf \
ncurses-dev xz-utils bc

History Command

apt-get install unicorn-factory
# [...] Permission denied
 
sudo !!
# sudo apt-get install unicorn-factory
 
sudo !!:s/install/uninstall
# Replace a word from previous command
 
sudo !-3
# Run the 3rd last command

Use Partial Command

echo hello world
# hello world
 
echo !:1
# hello
 
echo live long and prosper
# live long and prosper
 
echo !:3-4
# and prosper

Access the First and Last Parameter

echo live long and prosper
# live long and prosper
 
echo !^ !$
# live prosper
 
touch file1 file2 file3
rm !!*
# rm file1 file2 file3

Correct Previous Command

gti status
# Command 'gti' not found,
 
^gti^git
# git status

File Globing

ls *.sh # One or more character
ls project? # Single Character
touch foo{,2,5,10} # Expanded Form : touch foo foo2 foo5 foo10
 
touch project{1,2}/src/test/test{1,2,3}.py # Cartesian product outputs
touch {foo,bar}/{a..j}
 
ls /sys/bus/cpu/devices/cpu[0-9]* # Expand for all digits