Linux biff command
The program is named after a dog that belonged to one of the developers of BSD 4.0 at the University of California, Berkeley. (Biff was well-known for barking at the person delivering the mail.)
biff [ y | n ]
|y||Allow mail notification for the terminal.|
|n||Disable notification for the terminal.|
Enables mail alerts. This command displays no output, but when you have new mail, it alerts you at the terminal.