lineSendUserUserInfo (Compact 2013)

3/26/2014

This function sends user-user information to the remote party on the specified call.

Syntax

LONG WINAPI lineSendUserUserInfo(
  HCALL hCall,
  LPCSTR lpsUserUserInfo,
  DWORD dwSize 
);

Parameters

• hCall
  Handle to the call on which to send user-user information. The application must be an owner of the call. The call state of hCall must be connected, offering, accepted, or ringback.

• lpsUserUserInfo
  Pointer to a string containing user-user information to be sent to the remote party. User-user information is only sent if supported by the underlying network (see LINEDEVCAPS). The protocol discriminator field for the user-user information, if required, should appear as the first byte of the buffer pointed to by lpsUserUserInfo, and must be accounted for in the dwSize parameter.

• dwSize
  Size, in bytes, of the user-user information in lpsUserUserInfo.

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_OPERATIONUNAVAIL	The operation is unavailable.
LINEERR_INVALCALLSTATE	The call state is something other than connected, offering, accepted, or ringback.
LINEERR_OPERATIONFAILED	The operation failed.
LINEERR_INVALPOINTER	The pointer is invalid.
LINEERR_RESOURCEUNAVAIL	The resources are unavailable.
LINEERR_NOMEM	Not enough memory is available.
LINEERR_USERUSERINFOTOOBIG	The user-user information is too big.
LINEERR_NOTOWNER	The application is not an owner of this call.
LINEERR_UNINITIALIZED	A parameter is uninitialized.

Remarks

This function can be used to send user-user information at any time during a connected call. If the size of the specified information to be sent is larger than what can fit into a single network message (as in ISDN), the service provider is responsible for dividing the information into a sequence of chained network messages (using "more data").

User-user information can also be sent as part of call accept, call reject, and call redirect, and when making calls. User-user information can also be received. The received information is available through the call's call-information record. Whenever user-user information arrives after call offering or prior to call disconnect, a LINE_CALLINFO message with a UserUserInfo parameter notifies the application that user-user information in the call-information record has changed. If multiple network messages are chained, the information is assembled by the service provider and a single message is sent to the application.

Requirements

Header	tapi.h
Library	TAPI32.dll

See Also

Reference

TAPI Line Device Functions
LINE_CALLINFO (TAPI)
LINE_REPLY
LINEDEVCAPS