Saturday, April 4, 2015

Linux Commands


The Linux Command Line Commands

Chapter 1

date - print or set the system date and time
cal - displays a calendar and the date of Easter
df - report file system disk space usage
free - Display amount of free and used memory in the system

Chapter 2
pwd - print name of current/working directory
cd - changes directory
ls - list directory contents

Chapter 3
ls - List directory contents
file - Determine file type
less - View file contents

Chapter 4
cp - Copy files and directories
mv - Move/rename files and directories
mkdir - Create directories
rm - Remove files and directories
ln - Create hard and symbolic links
echo - displays line of text
touch - change file timestamps (if file does not exist, it creates one)

Chapter 5
type - Indicate how a command name is interpreted
which - Display which executable program will be executed
help - Get help for shell builtins
man - Display a command's manual page
apropos - Display a list of appropriate commands
info - Display a command's info entry
whatis - Display a very brief description of a command
alias - Create an alias for a command

Chapter 6
cat - Concatenate files
sort - Sort lines of text
uniq - Report or omit repeated lines
grep - Print lines matching a pattern
wc - Print newline, word, and byte counts for each file
head - Output the first part of a file
tail - Output the last part of a file
tee - Read from standard input and write to standard output and files


Chapter 7
echo – Display a line of text

Chapter 8
clear – Clear the screen
history – Display the contents of the history list


Chapter 9
umask – Set the default file permissions
su – Run a shell as another user
sudo – Execute a command as another user
chown – Change a file's owner
chgrp – Change a file's group ownership
passwd – Change a user's password

Chapter 10
ps – Report a snapshot of current processes
top – Display tasks
jobs – List active jobs
bg – Place a job in the background
fg – Place a job in the foreground
kill – Send a signal to a process
killall – Kill processes by name
shutdown – Shutdown or reboot the system