Instructs the current protocol to stop blocking calls.

DWORD dpnUnBlockCalls ( CTAHD ctahd )

ctahd CTA context handle returned by ctaCreateContext.

• SUCCESS
• CTAERR_INVALID_CTAHD
• CTAERR_INVALID_STATE

• DPNEVN_CALLS_UNBLOCKED

This function instructs the current protocol to stop blocking calls. When dpnBlockCalls is called, a transition to the blocking state occurs and calls are blocked. dpnUnBlockCalls is called to exit this state, which results in a transition from the blocking state to the Idle state. When this transition occurs, the DPNSS service generates the event DPNEVN_CALLS_UNBLOCKED.

Once the CTA context enters the Idle state, it can receive or place new calls.

If dpnBlockCalls is called and dpnUnBlockCalls is called before the protocol is able to start blocking calls, no event is received.

For more information about blocking calls, see Section 4.7, Blocking and Unblocking Calls.

dpnBlockCalls

int myUnBlockCalls( CTAHD ctahd )
{
   CTA_EVENT event;
    if( dpnUnBlockCalls( ctahd ) != SUCCESS )
    return MYFAILURE;
    do 
    {
    myGetEvent( &event );  /* see ctaWaitEvent example  */
    switch( event.id )
    {
    /* ...  */
    }
    } while( event.id != DPNEVN_CALLS_UNBLOCKED );
    return SUCCESS;
}

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