fn required_labjack_ip_from_env() -> Result<String, LJMError>Expand description
Reads the required LabJack IP address from environment variables.
LABJACK_IP is preferred. LABJACK_IDENTIFIER is accepted only when it is
an IPv4 address because this deployment path avoids broad discovery.
LABJACK_IP itself is not validated here.
ยงErrors
Returns LJMError::LibraryError if neither variable yields an address.