DFSIIDE0

DFSIIDE0 is the IMS dequeue support module that dequeues queue elements (QES) on IMS queue control blocks (QCBS). A QCB can be distinguished from a QE in that the enqueue pointer of a QCB is negative, while the forward pointer of a QE is non-negative. The backward pointer of a queued QE is negative.

Queue elements have a forward pointer, back pointer and an optional halfword for priority. The address of the forward pointer is always passed as the QE address.

Reference Sources

More information is available in the IMS SVSOURCE Library Data Set. See your IMS systems programmer.