SetCommMask (Compact 2013)

3/28/2014

This function specifies a set of events to be monitored for a communications device.

Syntax

BOOL SetCommMask(
  HANDLE hFile,
  DWORD dwEvtMask
);

Parameters

• hFile
  [in] Handle to the communications device, returned by the CreateFile function.

• dwEvtMask
  [in] Specifies the events to be enabled and immediately signals any thread waiting on the WaitCommEvent function. A value of zero disables all events.

  The following table shows possible values for this parameter.

  Value	Description
  EV_BREAK	A break was detected on input.
  EV_CTS	The clear-to-send (CTS) signal changed state.
  EV_DSR	The data-set-ready (DSR) signal changed state.
  EV_ERR	A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY.
  EV_RING	A ring indicator was detected.
  EV_RLSD	The receive-line-signal-detect (RLSD) signal changed state.
  EV_RXCHAR	A character was received and placed in the input buffer.
  EV_RXFLAG	The event character was received and placed in the input buffer. The event character is specified in the device's DCB structure, which is applied to a serial port by using the SetCommState function.
  EV_TXEMPTY	The last character in the output buffer was sent.

Return Value

Nonzero indicates success. Zero indicates failure. To obtain extended error information, call the GetLastError function.

Remarks

The SetCommState function specifies the set of events that can be monitored for a particular communications resource.

A handle to the communications resource can be specified in a call to the WaitCommEvent function, which waits for one of the events to occur.

To obtain the current event mask of a communications resource, use the GetCommMask function.

Requirements

See Also

Reference

Serial Communications Functions
DCB
GetCommMask
SetCommState
WaitCommEvent

Other Resources

CreateFile