The GetCommMask function retrieves the value of the event mask for a specified communications device.
BOOL GetCommMask(
HANDLE hFile, // handle to communications device
LPDWORD lpEvtMask // pointer to variable to get event mask
);
Value | Meaning |
---|---|
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_EVENT1 | An event of the first provider-specific type occured. |
EV_EVENT2 | An event of the second provider-specific type occured. |
EV_PERR | A printer error occured. |
EV_RING | A ring indicator was detected. |
EV_RLSD | The RLSD (receive-line-signal-detect) signal changed state. |
EV_RX80FULL | The receive buffer is 80 percent full. |
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. |
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
The GetCommMask function uses a 32-bit 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 SetCommMask function.
Windows CE: Windows CE does not support the following values for the lpEvtMask parameter:
EV_EVENT1
EV_EVENT2
EV_RX80FULL
EV_PERR
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winbase.h.
Import Library: Use kernel32.lib.
Communications Overview, Communication Functions, CreateFile, DCB, SetCommMask, WaitCommEvent,