The GetCommMask function retrieves the value of the event mask for a specified communications device.
BOOL GetCommMask(
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HANDLE hFile, |
// handle of communications device |
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LPDWORD lpEvtMask |
// address of variable to get event mask |
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); |
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Value |
Meaning |
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EV_BREAK |
A break was detected on input. |
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EV_CTS |
The CTS (clear-to-send) signal changed state. |
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EV_DSR |
The DSR (data-set-ready) signal changed state. |
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EV_ERR |
A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY. |
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EV_EVENT1 |
An event of the first provider-specific type occured. |
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EV_EVENT2 |
An event of the second provider-specific type occured. |
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EV_PERR |
A printer error occured. |
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EV_RING |
A ring indicator was detected. |
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EV_RLSD |
The RLSD (receive-line-signal-detect) signal changed state. |
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EV_RX80FULL |
The receive buffer is 80 percent full. |
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EV_RXCHAR |
A character was received and placed in the input buffer. |
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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. |
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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.
CreateFile, DCB, SetCommMask, WaitCommEvent,