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4/8/2010

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 CreateFilefunction.

dwEvtMask

[in] Specifies the events to be enabled and immediately signals any thread waiting on the WaitCommEventfunction. 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 DCBstructure, which is applied to a serial port by using the SetCommStatefunction.

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 GetLastErrorfunction.

Remarks

The SetCommStatefunction 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 WaitCommEventfunction, which waits for one of the events to occur.

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

Requirements

Header winbase.h
Library Serdev.lib
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also