IBM MQ APIs include MQSET, MQCMIT, MQBACK, MQCONN, MQOPEN, MQCLOSE, MQPUT, MQPUT1, MQGET, MQINQ, and MQBEGIN. 'MQGET1' is not a valid MQ API - the correct API for retrieving messages is MQGET. MQPUT1 exists as a single-call put operation, but there is no corresponding MQGET1.