INtime SDK Help
SetCommMask (Serial Communications)
INtime SDK v6 > About INtime > Networking and I/O > Serial Communications (COMM) > SetCommMask (Serial Communications)

Specifies a set of events to be monitored for a communications device.

BOOLEAN SetCommMask(
  COMMHANDLE hComm,    // handle to communications device
  DWORD dwEvtMask      // mask that identifies enabled events


[in] Handle to the communications device. OpenComm returns this handle.
[in] Specifies the events to be enabled. A value of zero disables all events. This parameter can be one or more of the following values:
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 SetCommState.
EV_TXEMPTY The last character in the output buffer was sent.

Return Values

0 (zero)
Failure. To determine the status, call GetLastRtError.


COMM channel is closed.
Invalid parameter.


This 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 WaitCommEvent, which waits for one of the events to occur. To get the current event mask of a communications resource, use GetCommMask.


Versions Defined in Include Link to
INtime 3.1 intime/rt/include/comm.h comm.h comm.lib
See Also