Meaning of `. ./script.sh` [duplicate]

Question

In the ESP32 documentation, I found this line:

. $HOME/esp/esp-idf/export.sh

What does the command . ./script.sh mean in bash ?

Answer 1

It is a shortcut for source ./script.sh. This command tells the shell to execute the contents of script.sh within the current shell session, rather than launching a new subprocess.

Sometimes, scripts define environment variables that need to persist in the current terminal session. To ensure these variables remain available, the script must be executed in the same shell environment.

See also:

• Source man page
• period Built-in