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Unix Shell - The if...else...fi statement
The if...else...fi statement is the next form of control statement that allows Shell to execute statements in more controlled way and making decision between two choices.
Syntax:
if [ expression ]
then
Statement(s) to be executed if expression is true
else
Statement(s) to be executed if expression is not true
fi
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Here Shell expression is evaluated. If the resulting value is true, given statement(s) are executed. If expression is false then no statement would be not executed.
Example:
If we take above example then it can be written in better way using if...else statement as follows:
#!/bin/sh
a=10
b=20
if [ $a == $b ]
then
echo "a is equal to b"
else
echo "a is not equal to b"
fi
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This will produce following result:
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