The SetPhoneLineLoopBack procedure is called to enable the looping back of received phone line audio data back to the transmit path of the same phone line. In other words, all data received on the phone line will immediately be echoed back to the far end. Note: Phone line loop back does not affect the reception of audio data. Your application will still receive audio data as normal.

Phone line loopback is disabled by default.

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


public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE SetPhoneLineLoopBack(
	int PhoneLine,
	bool LoopBackEnabled
Visual Basic (Declaration)
Public Function SetPhoneLineLoopBack ( _
	PhoneLine As Integer, _
	LoopBackEnabled As Boolean _
Visual C++
VoipMediaEngine..::.TELEPHONY_RETURN_VALUE SetPhoneLineLoopBack(
	int PhoneLine, 
	bool LoopBackEnabled
public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE SetPhoneLineLoopBack(
	int PhoneLine,
	boolean LoopBackEnabled


Type: System..::.Int32
The zero based phone line index.
Type: System..::.Boolean
The enable state of the phone line loop back. If TRUE, all audio data received by the phone line will be immediately retransmitted to the far end of the call. If FALSE, the line behaves as normal.

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
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)

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)

Application software called a telephony API procedure and specified an invalid phone line. Phone lines are numbered starting from zero. This error is most commonly returned when attempting to access phone lines in excess of the max number of lines supported by the telephony engine.

(API return value)



See Also