The CL command ENQUSRQ enqueues an entry to a user queue object. The queue can be both keyed or FIFO/LIFO.
ENQUSRQ Q(Q_LIB/Q_NAME) KEY(*none) MSG('message data') MSGLEN(nn)
/* nn: length of message data to enqueue */
To enqueue a keyed user queue
ENQUSRQ Q(Q_LIB/Q_NAME) KEY(mm) MSG('message data') MSGLEN(nn) /* mm: length of key data to enqueue */ /* nn: length of message data to enqueue */