Logical parent pointers

To determine the address of the parent of the segment with the invalid logical parent pointer, follow the LTF pointer or LTB pointer to the next LC on the logical twin chain. This twin should have an LP pointer pointing to the LP of the segment in error.

If there is no logical twin with a valid LP pointer, an error message for the LP should be produced because it should be expecting one or more logical children. The LCF pointer in the LP will point to the address of the invalid logical child.

If no LTF or LCF pointer is involved, an error message for the logical parent should be produced because the CTR field on the logical parent segment shows a discrepancy.

Since LP pointers are usually used during the unload process, an IMS reorganization cannot correct these errors. However, you can use the BMC UNLOAD PLUS product to reorganize this database using the LPCK(NO) option.