The SendEventNotification function can be called by application software to send an event notification to another telephony application or device. Events should only be sent to applications or devices that have previously made a request to receive such events. When another telephony application or device makes an attempt to subscribe to an event your application supports, your application will receive the SipSubscriptionReceived event. When your application processes this event, it must maintain the NOTIFY_HANDLE that is specified in the subscription event data. Your application can then use this handle to send notifications to the requesting application or device.

Namespace:  LanScape
Assembly:  LMEVoipManaged (in LMEVoipManaged.dll) Version: 6.0.5226.26700

Syntax

C#
public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE SendEventNotification(
	string EventParameter,
	uint NotificationResponseTimeoutMs,
	ref uint NotifyResponseCode
)
Visual Basic (Declaration)
Public Function SendEventNotification ( _
	EventParameter As String, _
	NotificationResponseTimeoutMs As UInteger, _
	ByRef NotifyResponseCode As UInteger _
) As VoipMediaEngine..::.TELEPHONY_RETURN_VALUE
Visual C++
public:
VoipMediaEngine..::.TELEPHONY_RETURN_VALUE SendEventNotification(
	String^ EventParameter, 
	unsigned int NotificationResponseTimeoutMs, 
	unsigned int% NotifyResponseCode
)
J#
public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE SendEventNotification(
	String EventParameter,
	UInt32 NotificationResponseTimeoutMs,
	/** @ref */UInt32 NotifyResponseCode
)

Parameters

EventParameter
Type: System..::.String
This is an optional event parameter that can be specified by application software. Any NULL terminated string value can be specified. If you do not need to use this parameter, then specify a zero length string such as "".
NotificationResponseTimeoutMs
Type: System..::.UInt32
The time in milliseconds for the event to be acknowledged by the far end receiving the event.
NotifyResponseCode
Type: System..::.UInt32 %
The SIP response code from the far end user agent.

Return Value

If the function succeeds, the return value will be SipSuccess.

If the function fails, the return value will be one of the following values as specified by the VoipMediaEngine..::.TELEPHONY_RETURN_VALUE data type.

Return ValueDescription
SipInvalidHandle
Application software specified an invalid telephony handle in one of the API procedures. This usually indicates memory corruption on the part of application software.

(API return value)

SipDomainNameNotDefined
Application software has configured proxy services but has not specified a SIP domain name using the EnableSipDomain(String) API procedure. This error can be generated for the following API procedures: TransferLine(String, String, Int32, Int32), MakeCall(String, String, UInt32, Int32, Boolean, UInt32), MakeCallUri(String, Boolean, Int32, Boolean, UInt32), and EnableSipRegisterServer(String, Boolean, Boolean, String, UInt32, UInt32, UInt32, UInt32, Boolean).

(API return value)

SipUnknownHost
A network address was specified as a UNC name and DNS was used to obtain the destination IP address. DNS could not resolve the UNC network name. Make sure the spelling you specified for the destination machine is correct.

(API return value)

SipEventNotifyNotAccepted
The destination device that received the event notification did not accept it. Generally this is caused by sending an event to a telephony device or application that did not previously subscribe to the event. This error can also occur if the far end device challenges the notify event. If the notify event is challenged, make sure you have properly set up authorization credentials using the AddAuthorizationCredentials(String, String, String) API procedure. To obtain the error information associated with a failed challenge, call the GetNotifyChallengeErrorData(UInt32, VoipMediaEngine..::.CHALLENGE_ERROR_DATA) API procedure.

(API return value)

SipEventNotifyResponseTimeOut
An application has sent an event notification to another telephony device and the receiving device has not responded in the specified time out period.

(API return value)

SipBadParameter
One of the telephony API procedures was called by application software and was passed a pointer to an invalid memory address. Normally this error will occur when application software passes NULL pointer values to the telephony API. For managed code applications, you should never see this error unless your process space has exhausted memory.

(API return value)

SipMemoryError
The telephony engine attempted to allocate system memory but the allocation failed. Make sure the host system has enough virtual memory. Increasing the amount of virtual memory can remove these errors, however if critical telephony engine code has been swapped out to disk and is not resident in physical memory, you may experience degraded audio/video performance. If you want to remove this error and obtain the best possible audio/video performance, make sure the host system has enough physical memory. To resolve this error, you may also want to consider disabling certain features of the media engine such as conference calling. You can also reduce memory requirements if you reduce the maximum signal length of internal media engine signal paths by specifying a smaller number for the MaxMixerLinebuffers member of the VoipMediaEngine..::.START_SIP_TELEPHONY_PARAMS class that is passed to the StartSipTelephony(VoipMediaEngine..::.START_SIP_TELEPHONY_PARAMS) and ReStartSipTelephony(VoipMediaEngine..::.START_SIP_TELEPHONY_PARAMS) API procedures.

(API return value, PHONE_LINE_NOTIFICATION)

Remarks

None.

See Also