The unit table contains a pointer to the UCB Pointer List as shown
in the following figure.
Figure 1. Output from Function Code 3 (Return UCB Addresses)
For unauthorized callers, the subpool default is 0. See function
code 10 for a description of how to change the default subpool. The
caller must free the number of bytes in the length field from the
subpool before exiting.
Register 15 contains one of the following return codes:
- Code
- Meaning
- 0
- The unit table contains the pointer to the UCB pointer list.
- 4
- The unit name could not be found in the EDT.
- 16
- Storage was not available for the UCB pointer list.
- 24
- The JESCT does not contain valid pointers.
- 28
- The required input is not specified or is not valid.
- 36
- An empty UCB list is being returned.