Windows Mobile 6.5
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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.

LONG WINAPI lineReleaseUserUserInfo(
  HCALL hCall 


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

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 failed.


Not enough memory is available.


The resources are unavailable.


The application is not an owner of this call.


A parameter is uninitialized.


The operation is unavailable.

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.

This function is for TAPI version 2.0 and later.

Windows Embedded CEWindows CE 1.0 and later
Windows MobileWindows Mobile Version 5.0 and later

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