Shell Scripting Cheat Sheet

Variables

Command	Description
VAR=value	Define variable
$VAR	Access variable
`command`	Command substitution

Flow Control

Command	Description
if	Condition check
then	Execute if condition is true
else	Execute if condition is false
elif	Other conditions
fi	End condition check
for	Loop
while	Loop while condition is true
do	Loop body
done	End loop

Functions

Command	Description
function_name() {}	Define function
return	Return from function
$?	Return value of last command

Script Control

Command	Description
#!/bin/bash	Specify interpreter used by script
chmod +x script.sh	Grant execute permission to script
./script.sh	Execute script