All you need to do is to modify your PROMPT_COMMAND environment variable so that it will send an alert (bell). The value of PROMPT_COMMAND is evaluated before every command prompt, meaning that it is evaluated after the end of every command.
To do so, open the startup file of your shell and append ; tput bel (or ; echo -e '\a') to the value of PROMPT_COMMAND. If PROMPT_COMMAND isn't present, create it with the value:
PROMPT_COMMAND+='; tput bel'
Now, you will get an alert after the end of every command, unless the terminal tab is focused when the command is finished.
Terminal gives you a couple options for configuring the alert (bell) behavior. You can access these by:
- Opening Preferences.
- Selecting Profiles.
- Selecting your profile.
- Clicking on the Advanced tab.
- Modifying the options under the Bell section.
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