5.4 Client Data Structures
There are four data structures defined in OLE.H that are of interest to an OLE client application. Two of the data structures contain single pointers that reference corresponding VTBL structures. Each VTBL structure contains pointers to various callback functions. The following chart identifies the single pointer structure names, the single pointer data types, and the corresponding VTBL names.
| Single-pointer name |
Single-pointer data type |
Corresponding VTBL |
| OLECLIENT |
LPOLECLIENTVTBL |
OLECLIENTVTBL |
| OLESTREAM |
LPOLESTREAMVTBL |
OLESTREAMVTBL |
The following table shows the contents of each data structure, as defined in OLE.H:
| Data Structure |
Contents, as defined in OLE.H |
| OLECLIENT |
A long pointer to the OLECLIENTVTBL structure. |
| OLECLIENTVTBL |
A single far pointer to the client's notification function: CallBack. |
| OLESTREAM |
A pointer to the OLESTREAMVTBL structure. |
| OLESTREAMVTBL |
Far pointers to the storage stream functions, Get and Put. |