Inside Macintosh: Telephony /

Chapter 4 - Call Appearances / Call Appearance Reference

Constants

Call Appearance States

A call appearance is always in a single state. Telephone network events, application function calls, and user actions can cause state changes. Telephone tools are responsible for updating the state appropriately.

Your application can detect state changes by explicitly checking the state (by calling the TELGetCAState function (page 4-54)) or by examining the messages received by your call appearance message handler. The messages notify you of state changes as well as activity associated with a given call appearance.

A call appearance's state is stored in the caState field of the call appearance structure (page 4-19). The following states are defined:

enum {
   telCAIdleState              = 0,
   telCAInUseState             = 1,
   telCAOfferState             = 2,
   telCAQueuedState            = 3,
   telCAAlertingState          = 4,
   telCADialToneState          = 5,
   telCADialingState           = 6,
   telCAWaitingState           = 7,
   telCARingingState           = 8,
   telCABusyState              = 9,
   telCAHeldState              = 10,
   telCAConferencedState       = 11,
   telCAActiveState            = 12,
   telCAReorderState           = 13,
   telCAConferencedHeldState   = 14,
   telCAUnknownState           = 15
};

Constant descriptions

telCAIdleState

There is no activity related to this call appearance (for instance, no connection or connection attempt is in progress). The idle state is the initial state of a newly created call appearance and the ending state when the connection or connection attempt is dropped. A call appearance can enter the idle state from any other state.

telCAInUseState

The call is active at another terminal.

telCAOfferState

The call is being offered to this terminal.

telCAQueuedState

The incoming call is queued at this terminal. A call enters the queued state when, because the local party is busy, the call is answered by a recording and queued for later handling.

telCAAlertingState

The call is alerting at this terminal.

telCADialToneState

The outgoing call has dial tone.

telCADialingState

The outgoing call is dialing.

telCAWaitingState

Dialing is complete and the outgoing call is waiting for a response, such as a busy signal or ring tone, from the destination. International calls often have such waiting periods.

telCARingingState

The outgoing call is ringing.

telCABusyState

The destination is busy.

telCAHeldState

The call has been put on hold by the local terminal.

telCAConferencedState

The call is part of a conference.

telCAActiveState

The call is active; parties are free to exchange information.

telCAReorderState

The telephone network has reported a reorder state. A reorder state can signify several conditions, including: (1) the call cannot be placed because of network congestion; (2) the call cannot be completed as dialed; (3) the local party has not hung up after the remote party hung up. Generally, your application should respond by hanging up and, if appropriate, trying the call again.

telCAConferencedHeldState

The call, part of a conference, has been put on hold by the local terminal.

telCAUnknownState

The state of the call is unknown.