Platform SDK: TAPI |
The lineDevSpecificFeature function enables service providers to provide access to features not offered by other TAPI functions. The meaning of these extensions are device specific, and taking advantage of these extensions requires the application to be fully aware of them.
LONG WINAPI lineDevSpecificFeature( HLINE hLine, DWORD dwFeature, LPVOID lpParams, DWORD dwSize );
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. Possible return values are:
LINEERR_INVALFEATURE, LINEERR_OPERATIONUNAVAIL, LINEERR_INVALLINEHANDLE, LINEERR_OPERATIONFAILED, LINEERR_INVALPOINTER, LINEERR_RESOURCEUNAVAIL, LINEERR_NOMEM, LINEERR_UNINITIALIZED.
Additional return values are device specific.
This operation is part of the Extended Telephony services. It provides access to a device-specific feature without defining its meaning. This operation is only available if the application has successfully negotiated a device-specific extension version.
This function provides the application with phone feature-button emulation capabilities. When an application invokes this operation, it specifies the equivalent of a button-press event. This method of invoking features is device dependent, as TAPI does not define their meaning. Typically, an application that relies on these device-specific extensions does not work with other service provider environments.
The structure pointed to by lpParams should not contain any pointers because they would not be properly translated (thunked) when running a 16-bit application in a 32-bit version of TAPI and vice versa.
Windows NT/2000: Requires Windows NT 4.0 SP3 or later.
Windows 95/98: Requires Windows 95 or later.
Version: Requires TAPI 1.3 or later.
Header: Declared in Tapi.h.
Library: Use Tapi32.lib.
TAPI 2.2 Reference Overview, Extended Telephony Services Reference, LINE_REPLY