$$ is an internal variable that stores the process ID of the script itself or the current bash instance.
Here is an example use case:
echo $$
This produces the following output:
darryl@Darryl-PC$ echo $$
8
$$ is an internal variable that stores the process ID of the script itself or the current bash instance.
Here is an example use case:
echo $$
This produces the following output:
darryl@Darryl-PC$ echo $$
8