Introduction to Linux
Contents
Data Streams
STDIO
Standard Input/Output (STDIO) contains 3 main streams of data associates with a file handle which are STDIN (file handle:0), STDOUT (file handle:1), and STDERR (file handle:2). STDIO is used to stream output data from one program to the input of another program.
STDIN
Standard Input (STDIN) is input from the keyboard.
STDOUT
Standard Output (STDOUT) is output sent to the terminal.
STDERR
Standard Error (STDERR) is errors sent to the terminal.
Basic Commands
These are the most basic commands that you should know as a Linux System Administrator.
Command Syntax
Commands that utilize the Bash shell follow this common syntax.
command [-options] [arguments]
Commands
echo
ls
pwd
cd
touch
cp
mkdir
cat
su
sudo
sudoedit
visudo
whoami
who
w
last
id
Power Management
shutdown
Command Information
man
apropos
whatis
info
Password Management
passwd
chage
User Management
useradd
usermod
userdel
Group Management
groupadd
groupmod
groupdel
