Bash Script If Variable Is Not Empty Code Example


Example 1: bash if null or empty


if [ -z "$variable" ];
  then echo "$variable is null";
  else echo "$variable is not null";
fi

Example 2: bash if variable is not empty


VAR=`echo Hello world`
if [[ -n "$VAR" ]] ; then echo "Variable is set" ; fi

Example 3: bash check if variable is empty


if [ -z "$var" ] #return true if $var is unset

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