Additional information about list APIs and user spaces

A list API returns only the number of list entries that can fit inside the user space. If you have *CHANGE authority to the user space, the list API can extend the user space when it is too small to contain the list.

Before you can use a list API to create a list, the *USRSPC object must exist.

If the user space is too small to contain the list and you have *CHANGE authority to the user space, the list API extends the user space to the nearest page boundary. If the user space is too small and you do not have *CHANGE authority, an authority error results. An extended user space is not truncated when you run the API again.

When you are creating a list into a user space and the user space cannot hold all of the available information (the list is greater than 16 MB in length), the API places as much information as possible in the user space and sends a message (typically CPF3CAA) to the user of the API. The returned list contains only the number of entries that can fit inside the user space (not the total number of entries available).