if [ expresion 1 ]
then
statement to be executed if expresion 1 is true
elif [ expression 2 ]
then
statement to be executed if expresion 2 is true
elif [ expression 3 ]
then
statement to be executed if expresion 3 is true
else
statement to be executed if no expresion is true
fi
On can use this command (expression) if we want select one of many blocks of code to execute.
It check one by one the expression and when is true it execute the statement and goes to next.
But if the expressions are false then it enters into else block and execute the else statement
#!/bin/sh
var1=10
var2=10
if[ var1==1var2 ]
then
echo "var1 is equal var2"
elif [ $var1 -gt $var2 ]
then
echo "var1 is greater than var2"
elif [ $var1 -lt $var2 ]
then
echo "var1 is not equal var2"
else
echo "none of the condition is ok"
fi