lineReleaseUserUserInfo (Compact 2013)

3/26/2014

This function informs the service provider that the application has processed the user-user information contained in the LINECALLINFO structure, and that subsequently received user-user information can now be written into that structure. The service provider sends a LINE_CALLINFO message indicating LINECALLINFOSTATE_USERUSERINFO when new information is available.

Syntax

LONG WINAPI lineReleaseUserUserInfo(
  HCALL hCall 
);

Parameters

• hCall
  Handle to the call. The application must be an owner of the call. The call state of hCall can be any state.

Return Value

Returns a positive request identifier if the function is completed asynchronously or a negative error number if an error occurs. The dwParam2 parameter of the corresponding LINE_REPLY message is zero if the function succeeds or it is a negative error number if an error occurs. The following table shows the return values for this function.

Value	Description
LINEERR_INVALCALLHANDLE	The handle to the call is invalid.
LINEERR_OPERATIONFAILED	The operation failed.
LINEERR_NOMEM	Not enough memory is available.
LINEERR_RESOURCEUNAVAIL	The resources are unavailable.
LINEERR_NOTOWNER	The application is not an owner of this call.
LINEERR_UNINITIALIZED	A parameter is uninitialized.
LINEERR_OPERATIONUNAVAIL	The operation is unavailable.

Remarks

The lineReleaseUserUserInfo function allows the application to control the flow of incoming user-user information on an ISDN connection. When a new, complete user-user information message is received, the service provider informs the application using a LINE_CALLINFO message (specifying LINECALLINFOSTATE_USERUSERINFO). Any number of applications can examine the information (using lineGetCallInfo), but the application owning the call controls when the information is released so that subsequent information can be reported. The service provider will not overwrite previous user-user information in LINECALLINFO with newer information until after lineReleaseUserUserInfo has been called. It is the responsibility of the service provider to buffer subsequently received user-user information until the previous information is released by the application owning the call.

Although this is a new function that older applications would not be expected to call, for backward compatibility, they should not be prevented from doing so. The function works the same way for all applications.

Requirements

Header	tapi.h
Library	TAPI32.dll

See Also

Reference

TAPI Line Device Functions
lineGetCallInfo
LINE_CALLINFO (TAPI)
LINE_REPLY
LINECALLINFO