TSPI_linePickup

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Windows Embedded CE 6.0 R3

4/8/2010

This function picks up a call alerting at the specified destination address and returns a call handle for the picked-up call. If invoked with NULL for the lpszDestAddress parameter, a group pickup is performed. If required by the device capabilities, the lpszGroupID parameter specifies the group identifier to which the alerting station belongs.

Syntax

LONG TSPIAPI TSPI_linePickup(
  DRV_REQUESTID dwRequestID,  
  HDRVLINE hdLine, 
  DWORD dwAddressID, 
  HTAPICALL htCall, 
  LPHDRVCALL lphdCall, 
  LPCWSTR lpszDestAddress,  
  LPCWSTR lpszGroupID 
);

Parameters

• dwRequestID
  Identifier of the asynchronous request.

• hdLine
  Handle to the line on which a call is to be picked up.

• dwAddressID
  Address on hdLine at which the pickup is to be originated. An address identifier is permanently associated with an address; the identifier remains constant across operating system upgrades.

• htCall
  TAPI handle to the new call. The service provider must save this and use it in all subsequent calls to the LINEEVENT procedure reporting events on the call.

• lphdCall
  Pointer to an HDRVCALL representing the service provider's identifier for the call. The service provider must fill this location with its handle for the call before this procedure returns. This handle is ignored by TAPI if the function results in an error.

• lpszDestAddress
  Pointer to a null-terminated Unicode string that contains the address whose call is to be picked up. The address is standard link format.

• lpszGroupID
  Pointer to a null-terminated Unicode string containing the group identifier to which the alerting station belongs. This parameter is required on some switches to pick up calls outside of the current pickup group.

  Note

  lpszGroupID can be specified by itself with a NULL pointer for lpszDestAddress. Alternatively, lpszGroupID can be specified in addition to lpszDestAddress, if required by the device. It can also be NULL itself.

Return Value

Returns dwRequestID, or an error number if an error occurs. The lResult actual parameter of the corresponding ASYNC_COMPLETION is zero if the function succeeds, or an error number if an error occurs. The following table shows the return values for this function.

Remarks

When a call has been picked up successfully, the service provider notifies TAPI with the LINE_CALLSTATE message about call state changes. The LINECALLINFO structure supplies information about the call that was picked up. It lists the reason for the call as pickup. This structure is available by calling the TSPI_lineGetCallInfofunction.

The service provider sets LINEADDRCAPFLAGS_PICKUPCALLWAIT to TRUE in the LINEADDRESSCAPS structure if TSPI_linePickup can be used to pick up a call for which the user has audibly detected the call-waiting signal, but for which the provider is unable to perform the detection. This gives the user a mechanism to answer a waiting call even though the service provider was unable to detect the call-waiting signal. When TSPI_linePickup is being used to pick up a call-waiting call, both lpszDestAddress and lpszGroupID pointer parameters are NULL. The service provider creates a new call handle for the waiting call and passes that handle to the user in lphdCall. The dwAddressID parameter is most often zero (particularly in single-line residential cases).

Once TSPI_linePickup is used to pick up the second call, the TSPI_lineSwapHold function can be used to toggle between them. The TSPI_lineDrop function can be used to drop one (and toggle to the other), and so forth. If the user wants to drop the current call and pick up the second call, they call TSPI_lineDrop when they get the call-waiting beep, wait for the second call to ring, and then call the TSPI_lineAnswer function on the new call handle. The service provider sets the LINEADDRFEATURE_PICKUP flag in the dwAddressFeatures member in the LINEADDRESSSTATUS structure to indicate when pickup is actually possible.

This function differs from the corresponding TAPI function in that it follows the TSPI model for beginning the lifetime of a call. TAPI and the service provider exchange opaque handles representing the call with one another. In addition, the service provider is permitted to do callbacks for the new call before it returns from this procedure. In any case, the service provider must also treat the handle it returned as "not yet valid" until after the matching ASYNC_COMPLETION function reports success. In other words, it must not issue any LINEEVENT messages for the new call or include it in call counts in messages or status data structures for the line.

Requirements

See Also

Reference

LINEEVENT
TSPI_lineAnswer
TSPI_lineDrop
TSPI_lineGetCallInfo
TSPI_lineGetCallStatus
TSPI_lineSwapHold