In bash, how to store a return value in a variable?

Question

I know some very basic commands in Linux and am trying to write some scripts. I have written a function which evaluates the sum of last 2-digits in a 5-digit number. The function should concatenate this resultant sum in between the last 2-digits and return it. The reason I want to return this value is because I will be using this value in the other function.

Ex: if I have 12345, then my function will calculate 4+5 and return 495.

#!/bin/bash  set -x echo "enter: "         read input  function password_formula {         length=${#input}         last_two=${input:length-2:length}         first=`echo $last_two| sed -e 's/\(.\)/\1 /g'|awk '{print $2}'`         second=`echo $last_two| sed -e 's/\(.\)/\1 /g'|awk '{print $1}'`         let sum=$first+$second         sum_len=${#sum}         echo $second         echo $sum          if [ $sum -gt 9 ]         then                sum=${sum:1}         fi          value=$second$sum$first         return $value } result=$(password_formula) echo $result 

I am trying to echo and see the result but I am getting the output as shown below.

-bash-3.2$ ./file2.sh  +++ password_formula +++ echo 'enter: ' +++ read input 12385 +++ length=8 +++ last_two=85 ++++ echo 85 ++++ sed -e 's/\(.\)/\1 /g' ++++ awk '{print $2}' +++ first=5 ++++ echo 85 ++++ sed -e 's/\(.\)/\1 /g' ++++ awk '{print $1}' +++ second=8 +++ let sum=5+8 +++ sum_len=2 +++ echo 5 +++ echo 8 +++ echo 13 +++ '[' 13 -gt 9 ']' +++ sum=3 +++ value=835 +++ return 835 ++ result='enter:  5 8 13' ++ echo enter: 5 8 13 enter: 5 8 13 

I also tried to print the result as:

password_formula RESULT=$? echo $RESULT 

But that is giving some unknown value:

++ RESULT=67 ++ echo 67 67 

How can I properly store the correct value and print (to double check) on the screen?

Thanks in advance.

Answer 1

Simplest answer:

the return code from a function can be only a value in the range from 0 to 255 . To store this value in a variable you have to do like in this example:

#!/bin/bash  function returnfunction {     # example value between 0-255 to be returned      return 23 }  # note that the value has to be stored immediately after the function call : returnfunction myreturnvalue=$?  echo "myreturnvalue is "$myreturnvalue