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UNIX : Using IF in bash



The IF statement is used to test the given condition and based on the truth value of that the expression the statement followed is executed.Otherwise the else part is executed.

The basic structure of if is as follows.

If [[ expression ]];then

     expression

elif [[expression ]];then

     expression

else

     expression

1) Integer comparison

 

 2) String comparison

 

 3) Using multiple conditions in IF statement

 

 4) Compare regular expression in bash




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