Bash: Update the parent variable from function variable

Question

i want to update the variable a become 2. But the result is always 1. Is there anyway to do it?

a=1
aple(){
        a=2
        echo "apel"
}
b=`aple`
echo $a

anubhava · Accepted Answer · 2014-10-18 10:37:54Z

1

Problem is in this call:

b=`aple`

Which invokes aple function in a subshell hence changes made in subshell are lost and not visible in the parent shell.

Call your function as:

aple
echo $a
2

As per your comments if you want to assign a value to b also then have your function as:

a=1
b=
aple() { a=2; b="apel"; }

Then call it as:

aple
echo "$b:$a"
apel:2

answered Oct 18, 2014 at 9:54

anubhava

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2 Comments

if i still want to use b=apel, is there anyway to update it?

b=`apel` will always create a sub shell hence changes will be lost in parent shell.