Jekyll - TCPServer Error: Address already in use - bind(2)

Trouble running Jekyll after the server fails to stop properly.

Just ran into this error on Macbook Pro with Jekyll…

$> jekyll 2.5.3 Error: Address already in use - bind(2)

The following worked for me…

$> lsof -wni tcp:4000

Then, I used the PID column number to kill the process.

$> kill -9 PID