Adds listeners to a connection.

DWORD ppxAddListeners ( PPXHD ppxhd,
PPX_MVIP_ADDR listeners[],
unsigned count )

ppxhd Handle returned by ppxCreateConnection or by ppxOpenConnection.

listeners[] Pointer to a PPX_MVIP_ADDR structure. The structure is defined as follows:

typedef struct
{
 DWORD switch_number;
 DWORD bus;      
 DWORD stream;     
 DWORD timeslot;    
} PPX_MVIP_ADDR

See the Details section for a description of these fields.

count Number of listeners to add.

• SUCCESS
• CTAERR_DRIVER_ERROR
  The underlying driver retrieved an unrecognized error. Call swiGetLastError to retrieve the MVIP device error code.
• CTAERR_INVALID_HANDLE
  ppxhd is not a valid connection handle.
• CTAERR_NOT_FOUND
  One of the listeners is not defined in the Point-to-Point Switching configuration file.
• CTAERR_OUT_OF_MEMORY
  Unable to allocate memory.
• PPXERR_COMM_FAILURE
  Problems were encountered when communicating with the PPX server.
• PPXERR_DISABLED
  The switch number specified has been disabled.
• PPXERR_DRIVER_OPEN_FAILED
  The driver open failed, or the driver DLL or device was not found.
• PPXERR_INVALID_COUNT
  The number of supplied listeners is less than count.
• PPXERR_INVALID_SWITCH
  Switch number specified is inaccessible from the specified bus:stream:timeslot.
• PPXERR_NO_PATH
  Could not find a path from talker to one of the listeners assigned to the connection.
• PPXERR_NOT_LISTENER
  One of the listeners is incapable of receiving output from the connection.
• SWIERR_INVALID_STREAM
  One or more of the streams specified is invalid.
• SWIERR_INVALID_TIMESLOT
  One or more of the timeslots specified is invalid.

• None.

This function adds listeners to a connection. If the connection already has a talker attached, switch connections are made to connect the listeners to the talker. If the talker and listeners are on different boards, telephony bus timeslots are used to make the connection.

If no talker is attached, the listeners have the default pattern of the connection sent to them.

The PPX_MVIP_ADDR structure contains the following fields:

Field	Description
switch_number	Switch number of the board as defined in ppx.cfg.
bus	Acceptable values are: MVIP95_MVIP_BUS MVIP95_LOCAL_BUS
stream	The stream number of the listener.
timeslot	The timeslot of the listener.

ppxCreateConnection, ppxOpenConnection, ppxRemoveListeners, ppxSetDefaultPattern, ppxSetTalker

DWORD KeepOnHold( MYCONTEXT *cx )
{
    DWORD e;
    unsigned port_id;  
    CTA_EVENT event;
    
    port_id = cx->id;
    
    if( cx->conn_state != CTX_ONHOLD )
    {
        /* Need to add as a listener to the hold message
         * connection.
         */
         
        cx->conn_state = CTX_ONHOLD;
                             
        listeners[port_id].switch_number = cx->swi; 
        listeners[port_id].bus = MVIP95_LOCAL_BUS;
        listeners[port_id].stream = 1;
        listeners[port_id].timeslot = cx->time_slot;
  
        e = ppxAddListeners( ppxhd[HOLD_MSG], 
                             &listeners[port_id], 1 );  
        if (e != SUCCESS)
        {
            return e;
        }
    }