Windows Mobile 6.5
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This function sends user-user information to the remote party on the specified call.

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


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.


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.


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

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


The handle to the call is invalid.


The operation is unavailable.


The call state is something other than connected, offering, accepted, or ringback.


The operation failed.


The pointer is invalid.


The resources are unavailable.


Not enough memory is available.


The user-user information is too big.


The application is not an owner of this call.


A parameter is uninitialized.

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.

This function is for TAPI version 2.0 and later.

Windows Embedded CEWindows CE 3.0 and later
Windows MobileWindows Mobile Version 5.0 and later

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