HP-UX C SIP Stack Programmer's Guide (Novembery 2007)

Working with Register-Clients 141

Registering Application Callbacks

/*===================================================================*/

typedef void

(RVCALLCONV * RvSipRegClientStateChangedEv)(

IN RvSipRegClientHandle hRegClient,

IN RvSipAppRegClientHandle hAppRegClient,

IN RvSipRegClientState eNewState,

IN RvSipRegClientStateChangeReasonm eReason);

/*===================================================================*/

You can implement any callbacks you find necessary, according to the callback

function prototypes in the Register-Client API. All callback functions are

included in a structure called RvSipRegClientEvHandler. This event handler

structure is where you should set your callback function pointers and is given as

a parameter to RvSipRegClientMgrSetEvHandlers(). The register-client notifies

you when the event occurs using the callback functions you implemented.

If you do not wish to be notified of certain events, enter a NULL value for the

callback functions that manage those events in RvSipRegClientEvHandler.

Although you can set the event handlers at any time, it is customary to set them

immediately after RvSipStackConstruct() so that the application immediately

receives all necessary notifications.

REGISTERING

APPLICATION

ALLBACKS

To register an application callback, you must first define the callback according

to the prototype. The following code demonstrates an implementation of the

RvSipEventStateChanged() callback function.