GetCommMask
The GetCommMask
function retrieves the value of the event mask for a specified communications
device.
BOOL GetCommMask(
|
HANDLE hFile, |
// handle of
communications device |
|
LPDWORD lpEvtMask |
// address of
variable to get event mask |
|
); |
|
Parameters
hFile
Identifies
the communications device. The CreateFile function returns this handle.
lpEvtMask
Points to the
32-bit variable to be filled with a mask of events that are currently enabled.
This parameter can be one or more of the following values:
|
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. |
Return Values
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.
Remarks
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.
See Also