pub fn open_streamer_labjack_from_env() -> Result<i32, LJMError>Expand description
Opens, verifies, and self-tests the LabJack configured by environment.
Opens a T7 over Ethernet at the configured IP address, then checks the device
type, the IP reported by the handle (skipped when LJM reports none), and the
optional serial number. As a self-test it reads STREAM_SETTLING_US and writes
the same value back. If a stale active stream blocks the write, it sends
stream_stop once and retries. If any check fails, the handle is closed before
the error is returned.
§Returns
The LJM device handle. The caller owns it and must close it.
§Errors
Returns LJMError::LibraryError if no IP address is configured, the device
cannot be opened, the handle info cannot be read, the device is not a T7, its
IP or serial number does not match, or the self-test read or write fails
(including after stream_stop, or if stream_stop itself fails).