A handle to the communications device. The
CreateFile function returns this handle.
A pointer to the variable that receives a mask of events that are currently enabled. This parameter can be one or more of the following values.
A break was detected on input.
The CTS (clear-to-send) signal changed state.
The DSR (data-set-ready) signal changed state.
A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY.
An event of the first provider-specific type occurred.
An event of the second provider-specific type occurred.
A printer error occurred.
A ring indicator was detected.
The RLSD (receive-line-signal-detect) signal changed state.
The receive buffer is 80 percent full.
A character was received and placed in the input buffer.
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
The last character in the output buffer was sent.
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call
GetCommMask function uses a mask variable to indicate 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 modify the event mask of a communications resource, use the