awk + verify field if zero

Question

hi all To find if field 5 has I use the:

   [[ -z ` echo $LINE  | awk '{print $5}' ` ]]

my question if there is another elegant way to verify if field 5 is zero?

THX Yael

Answer 1

After length5=$(echo $LINE | awk '{ print length($5)}') the variable $lenght5 will contain the length of field 5;

Note: in your example line, if ttt were empty, yyy would be field 5, so be careful: you can use

awk -F' '

instead of awk to make the space the field delimiter, so that 2 spaces = empty field....

Answer 2

This will pass if the 5th field is the string 0 (and won't if it's 00, 0.0, or it's absent etc).

#!/bin/bash

LINE="123 aaa ddd ggg 0 yyy hhh"

if [[ "0" = `echo ${LINE}  | awk '{print $5}'` ]]
then
   echo "5th field is string '0'"
else
   echo "5th field isn't string '0'"
fi

Does that do what you want?

It would be useful if you provided more example input.