- LB_GETSELCOUNT/LB_GETSELITEMS (LB_ERR is returned if this is a single-selection listbox; are there actual errors?) (sysData.selectedIndices())
- LB_GETTEXTLEN/LB_GETTEXT (LB_ERR is returned if the given index is invalid, but since we get indices from LB_GETSELITEMS this shouldn't happen; are there actual errors?) (sysData.selectedTexts())