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TSPI_lineSetMediaMode (Windows Embedded CE 6.0)

1/6/2010

This function changes the call's media as stored in the call's LINECALLINFO structure.

Syntax

LONG TSPIAPI TSPI_lineSetMediaMode(
  HDRVCALL hdCall,  
  DWORD dwMediaMode 
);

Parameters

  • hdCall
    Handle to the call undergoing a change in media type. The call state of hdCall can be any state.
  • dwMediaMode
    New media types for the call. As long as the LINEMEDIAMODE_UNKNOWN media type flag is set, multiple other media type flags can be set as well. This is used to identify a call's media type as not fully determined, but narrowed down to one of just a small set of specified media types. If the LINEMEDIAMODE_UNKNOWN flag is not set, only a single media type can be specified. This parameter uses one (or more) of the LINEMEDIAMODE constants.

Return Value

Returns zero if the function succeeds, or an error number if an error occurs. The following table shows the return values for this method.

Value Description

LINEERR_INVALCALLHANDLE

The handle to the call is invalid.

LINEERR_OPERATIONUNAVAIL

The operation is unavailable.

LINEERR_INVALMEDIAMODE

The media mode is invalid.

LINEERR_OPERATIONFAILED

The operation failed.

LINEERR_NOMEM

Not enough memory is available.

LINEERR_RESOURCEUNAVAIL

The resource is unavailable.

Remarks

Other than changing the call's media as stored in the call's LINECALLINFO structure, this procedure is simply advisory in the sense that it indicates an expected media change that is about to occur, rather than forcing a specific change to the call. Typical usage is to set a call's media type to a specific known media type, or to exclude possible media types as long as the call's media type is not fully known (the UNKNOWN media type flag is set).

TAPI makes the following guarantees regarding the passed media type: (1) there is at least one bit set, (2) there are no reserved bits set, and (3) if more than one bit is set, "Unknown" is also set. The service provider must perform any further validity checks on the media types, such as checking whether any media types are indeed supported by the service provider.

Requirements

Header tapicomn.h
Library coredll.lib
Windows Embedded CE Windows CE 3.0 and later

See Also

Reference

TSPI Line Device Functions
TSPI_lineGetCallInfo