Variables value gets lost in subshell

Question

This bash script concatenates the names for jar files to a classpath (variable CP), in the while loop the value is correct but is lost in the subshell as descibed in this re

Answer 1

Implicit subshells are confusing; always make them explicit by using parentheses. To solve your problem, just move the echo inside the subshell.

#!/bin/bash
CP="AAA"
func() {
  ls -1 | (
    while read JAR
    do
      if [ ! -z "$CP" ]; then
        CP=${CP}':'
      fi
      CP=${CP}${JAR}
    done
    echo $CP
  )
}
func