When issuing a read, call_port can try to exit.

[critch]

I have a section of code that is trying to handle incoming data till a marker is set and we can start the framing portion. The UART is a USB gadget that is always present, so open always succeeds. Sometimes a Circuits.UART.read(pid, 1000) results in an exit due to an odd issue with timeout or other. The documentation for read/2 is that it returns {:ok, buffer} or {:error, reason}, but does not cover the exit condition. Either this exit should be conditional, or documented.

Here is a link to the problematic line that calls exit.

circuits_uart/lib/circuits_uart.ex

Line 554 in 5ef46d9

exit(:port_timed_out)