How to check if null in bash

01 Feb 2010

Expanding on the previous bash not null post to check if a string is null

String='' # Zero-length ("null") string variable. 

if [ -z "$String" ] 
then 
 echo "\$String is null." 
else 
 echo "\$String is NOT null." 
fi # $String is null. 

Justin Kelly

Justin Kelly

Data Engineeer, Business Analytics, Web Developer, Library Technology specialising in PHP and Tableau

Based in Melbourne, Australia

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