function fun1(){
  return 34
}
function fun2(){
  local res=$(fun1)
  echo $res
}

function fun1(){
  echo 34
}

function fun2(){
  local res=$(fun1)
  echo $res
}

function fun1(){
  return 34
}

function fun2(){
  fun1
  local res=$?
  echo $res
}

fun1 (){
  return 34
}

fun2 (){
  fun1
  local res=$?
  echo $res
}

encrypt() {
    gpg -c -o- $1 # encrypt data in filename to stdout (asks for a passphrase)
}

encrypt public.dat > private.dat # write function result to file

function fun1(){
  return 34
}

function fun2(){
  local res=$(fun1)
  echo $? # <-- Always echos 0 since the 'local' command passes.

  res=$(fun1)
  echo $?  #<-- Outputs 34
}

POINTER= # used for function return values

my_function() {
    # do stuff
    POINTER="my_function_return"
}

my_other_function() {
    # do stuff
    POINTER="my_other_function_return"
}

my_function
RESULT="$POINTER"

my_other_function
RESULT="$POINTER"

my_function() {
    echo "-> my_function()"
    # do stuff
    POINTER="my_function_return"
    echo "<- my_function. $POINTER"
}

#!/bin/bash

##A 6-element array used for returning
##values from functions:
declare -a RET_ARR
RET_ARR[0]="A"
RET_ARR[1]="B"
RET_ARR[2]="C"
RET_ARR[3]="D"
RET_ARR[4]="E"
RET_ARR[5]="F"


function FN_MULTIPLE_RETURN_VALUES(){

   ##give the positional arguments/inputs
   ##$1 and $2 some sensible names:
   local out_dex_1="$1" ##output index
   local out_dex_2="$2" ##output index

   ##Echo for debugging:
   echo "running: FN_MULTIPLE_RETURN_VALUES"

   ##Here: Calculate output values:
   local op_var_1="Hello"
   local op_var_2="World"

   ##set the return values:
   RET_ARR[ $out_dex_1 ]=$op_var_1
   RET_ARR[ $out_dex_2 ]=$op_var_2
}


echo "FN_MULTIPLE_RETURN_VALUES EXAMPLES:"
echo "-------------------------------------------"
fn="FN_MULTIPLE_RETURN_VALUES"
out_dex_a=0
out_dex_b=1
eval $fn $out_dex_a $out_dex_b  ##<--Call function
a=${RET_ARR[0]} && echo "RET_ARR[0]: $a "
b=${RET_ARR[1]} && echo "RET_ARR[1]: $b "
echo
##----------------------------------------------##
c="2"
d="3"
FN_MULTIPLE_RETURN_VALUES $c $d ##<--Call function
c_res=${RET_ARR[2]} && echo "RET_ARR[2]: $c_res "
d_res=${RET_ARR[3]} && echo "RET_ARR[3]: $d_res "
echo
##----------------------------------------------##
FN_MULTIPLE_RETURN_VALUES 4 5  ##<---Call function
e=${RET_ARR[4]} && echo "RET_ARR[4]: $e "
f=${RET_ARR[5]} && echo "RET_ARR[5]: $f "
echo
##----------------------------------------------##


read -p "Press Enter To Exit:"

FN_MULTIPLE_RETURN_VALUES EXAMPLES:
-------------------------------------------
running: FN_MULTIPLE_RETURN_VALUES
RET_ARR[0]: Hello
RET_ARR[1]: World

running: FN_MULTIPLE_RETURN_VALUES
RET_ARR[2]: Hello
RET_ARR[3]: World

running: FN_MULTIPLE_RETURN_VALUES
RET_ARR[4]: Hello
RET_ARR[5]: World

Press Enter To Exit: