How to get one line from com port and disconnect?

Question

linux

Given:
A computer with (Linux Debian on board) and Arduino, which once a second issues a certain line in the com port.
how can I get a line and disconnect from the com port.
ideally sh script that will echo this line to the console

Answer 1

https://gist.github.com/tmbdev/5772607 can dig in that direction.