When performing event subscription operations, your application will be notified when authentication challenges fail and subscription operations can not continue.

If this is the case, then your application will receive the immediate event SipSubscriptionRequiresAuthentication. Application software can then call the GetSubscribeChallengeErrorData(UInt32, VoipMediaEngine..::.CHALLENGE_ERROR_DATA) API procedure to obtain the subscribe challenge error data. Applications use this challenge error data to display subscription "authorization required" messages to users.

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

Syntax

C#
public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE GetSubscribeChallengeErrorData(
	uint EventSubscribeHandle,
	VoipMediaEngine..::.CHALLENGE_ERROR_DATA ChallengeErrorData
)
Visual Basic (Declaration)
Public Function GetSubscribeChallengeErrorData ( _
	EventSubscribeHandle As UInteger, _
	ChallengeErrorData As VoipMediaEngine..::.CHALLENGE_ERROR_DATA _
) As VoipMediaEngine..::.TELEPHONY_RETURN_VALUE
Visual C++
public:
VoipMediaEngine..::.TELEPHONY_RETURN_VALUE GetSubscribeChallengeErrorData(
	unsigned int EventSubscribeHandle, 
	VoipMediaEngine..::.CHALLENGE_ERROR_DATA^ ChallengeErrorData
)
J#
public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE GetSubscribeChallengeErrorData(
	UInt32 EventSubscribeHandle,
	VoipMediaEngine..::.CHALLENGE_ERROR_DATA ChallengeErrorData
)

Parameters

EventSubscribeHandle
Type: System..::.UInt32
A "handle" to a valid event subscription. This handle must be the result of a previous call to the StartEventSubscription(VoipMediaEngine, String, String, String, UInt32, Boolean, String, String, UInt32, UInt32, UInt32) API procedure.
ChallengeErrorData
Type: LanScape..::.VoipMediaEngine..::.CHALLENGE_ERROR_DATA
A referenceto a variable of type VoipMediaEngine..::.CHALLENGE_ERROR_DATA. When this API procedure is called, this variable will be initialized with authentication error data.

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
SipCallFailure
This value is returned by telephony API procedures to indicate general API failure. This error value is used as a "catch all error". If you receive this error, check to make sure that all parameters specified in the API procedure call are correct. Particularly, verify that pointers to memory regions are valid. This error return value is only used if a mapping to another specific error value does not exist.

(API return value)

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)

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)

Remarks

None.

See Also