I have two shell scripts.

1. SetEnvVariable.sh
2. MigrationOperator.sh

In SetEnvVariable.sh I’m setting a variable called CONNECT_POD_RESOURCE_NAME by doing below

export CONNECT_POD_RESOURCE_NAME="connect-200"

From MigrationOperator.sh I am calling the SetEnvVariable.sh as below

source ./SetEnvVariable.sh

Now I have a strange observation,

If in my MigrationOperator.sh I have a code like below,

echo $CONNECT_POD_RESOURCE_NAME
var=$CONNECT_POD_RESOURCE_NAME
echo $var
var+=",1/1,RUNNING"
echo $var

The output looks like,

This output is unexpected to me as I was expected that at last echo, $var should have a proper concated value.

However,
if my MigrationOperator script has the code like,

export CONNECT_POD_RESOURCE_NAME="connect-200"
echo $CONNECT_POD_RESOURCE_NAME
var=$CONNECT_POD_RESOURCE_NAME
echo $var
var+=",1/1,RUNNING"
echo $var

the output looks proper,

what I don’t understand is when, CONNECT_POD_RESOURCE_NAME (and later var) variable has proper value in it, how come string concate works fine in one case and doesn’t in other case?

And what is better way to set the variables in a separate script (here in this e.g. SetEnvVariable.sh) and still be able to use it (directly and by string manipulation) in caller script?