SetCommMask (Windows CE 5.0)

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

BOOLSetCommMask(HANDLEhFile, DWORDdwEvtMask);


  • hFile
    [in] Handle to the communications device.

    The CreateFile function returns this handle.

  • 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 CTS (clear-to-send) signal changed state.
    EV_DSR The DSR (data-set-ready) 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 RLSD (receive-line-signal-detect) 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 Values

Nonzero indicates success.

Zero indicates failure.

To obtain extended error information, call the GetLastError function.


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.


OS Versions: Windows CE 1.0 and later.
Header: Winbase.h.
Link Library: Serdev.lib.

See Also

CreateFile | DCB | GetCommMask | SetCommState | WaitCommEvent

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