This read-only Gauge reports the number of bit errors that have been deliberately injected into the test pattern currently being sent, via devDS1SendControlInjectErr, capped at a maximum value of 99,999. Admins use it to track how many test errors they've injected during a validation session, confirming the injected-error count matches what the far-end monitoring should be reporting. A value of 5 after five inject(2) writes confirms each injection was successfully applied to the outgoing pattern.