Sharing variables in different bash scripts-CodePudding

Let's say I have a script script1.sh like

#!/bin/bash
#do something
export THING="a"
source script2.sh & #so running in background
sleep 1 #or do something
export THING="b"
source script2.sh & #so running in background

So exporting a variable THING, read by script2.sh:

#!/bin/bash                                                                                                                                    

echo "PRINT1: ${THING}"
sleep 5
echo "PRINT2: ${THING}"

Is it correct to assume that script2.sh is "freezing" the value of THING at the moment of the call? (i.e. so it's not changing during the executing even if running in background).

I tested this and it seems the case but I want to check that it is the expected general behavior.

Thanks in advance, SL

CodePudding user response：

Is it correct to assume that script2.sh is "freezing" the value of THING at the moment of the call?

Yes. The value is not "frozen", you can change it. It's just a copy.

Every process has its own environment. The child process is created as a copy of the current environment at the moment of the child creation.