AWK: return value to shell script

Question

Is it possible to have an awk command within a bash script return values to a bash variable, i.e.,if my awk script does some arithmetic operations, can I store the answers in variables so, they can be accessed in the bash script. If possible, how to distinguish between multiple return variables. Thanks.

Answer 1

No. You can use exit to return an error code, but in general you can't modify the shell environment from a subprocess.

You can also, of course, print the desired content in awk and put it into variables in bash by using read:

read a b c <<< $(echo "foo" | awk '{ print $1; print $1; print $1 }')

Now $a, $b and $c are all 'foo'. Note that you have to use the <<<$() syntax to get read to work. If you use a pipeline of any sort a subprocess is created too and the environment read creates the variables in is lost when the pipeline is done executing.

Answer 2

var=$(awk '{ print $1}')

This should set var to the output of awk. Then you can use string functions or whatever from there to differentiate within the value or have awk print only the part you want.