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Register a callback functions which is called when the workspace
send commands to DBS. When called with a NULL function or a NULL value,
restores the default handler in LIBLINCKS. The callback
function is declared to return to a integer value, even though it
is not used yet. The `extra' argument is passed to the callback
function when it is called.
The possible value for `what' which correspond to different messages
sent to DBS are:
- RCB_EDIT
The specified function is called when a new version is created
for an object (or a version node).
- RCB_STORE
The specified function is called when a node is stored.
- RCB_RETRIEVE
The specified function is called when a workspace wants to
retrieve a node.
- RCB_RELEASE
The specified function is called when the workspace has released
an object.
The call format of the callback function is:
(*callback)(void *extra, int index, int moltype);
where the argument have the following declaration and content:
- void *extra
is passed in to the LIBLINCKS function as an extra
application program parameter. It is not used within
LIBLINCKS, and is intended as a pointer to a call block
for application program arguments.
- int index
is the node index to the object sent to the database
(see section 4.3).
- int moltype
Type of node specified in index, can be
VSS, VSE, VS, VSH, OTHER, or
UNKNOWN_TYPE defined in dbcodes.h
- UNKNOWN_TYPE marks a node whose type is ``unknown''.
- OTHER marks that a node is a version node
(``user's data'').
- VSH marks hidden history node (no PEN).
- VS marks history node (PEN).
- VSE marks history node at pre-edit.
- VSS marks history node a final store.
The function returns the previous callback function, if any.
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Up: RCB_REGISTERCALLBACK(whatcallback,extra)
Previous: RCB_PEN_NOPOLL
Martin Sjolin
Thu Jun 15 20:41:59 MET DST 1995