Modifying global variables inside a function in Bash
In this article, we will learn how to modify global variables within a Bash function.
Modifying global variables inside a function in Bash
If you declare your variables in a script, every variable in Bash is global by default, which means it can be accessed by any function, script, or even external shell.
If you declare a variable as global in a function, you can access its value even when the function is not executed.
By default, any variable you declare is a global variable. If you define a variable outside a function, you will not face any problems when using it inside a function.
Code example:
e=2
function example1() {
a=4
echo "Today"
}
example1
echo "$a"
Output:
Today
4
On the other hand, if we assign the result of the function to a variable, the value of the global variable a does not change.
Code example:
a=2
function example1() {
a=4
echo "Today"
}
ret=$(example1)
echo "$ret"
echo "$a"
Output:
Today
2
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