Sharing variables between shell scripts

Question

I have a shell script (let's call it parent.sh) which calls another shell script (child.sh), passing it an argument.

The child script does some work and sets a value in a variable called create_sql. I want to access this create_sql variable from the parent script which invoked it.

I am calling the child script from within the parent script like this:

./child.sh "$dictionary"

and straight afterwards I have the line:

echo "The resulting create script is: "$create_sql

However, there is no value being output, however, in the child script I am doing the same thing and the variable is definitely set.

How can I get this to work so that I can read variables created by the child script?

Answer 1

If you child.sh print on standard output $create_sql value, you could get it in parent script:

  create_sql=`./child.sh "$dictionary"`

After this line, you should test child.sh exit value with $? and if it returns 0 you could use $create_sql variable.

This approach is useful when script is like a function, otherwise is better follow muru suggested answer.