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#define INCL_DOSDEVIOCTL
 
USHORT DosDevIOCtl(pfEvent, 0L, 0x0072, 0x0001, hDevice)
PUSHORT pfEvent;    /* pointer to variable for events */
HFILE hDevice;      /* device handle                  */
 
The ASYNC_GETCOMMEVENT function retrieves the communications event flags
from the internally maintained event word. After the function copies the
event flags to the specified variable, it clears the event word.
 
Parameter  Description
────────────────────────────────────────────────────────────────────────────
 
pfEvent    Points to the variable that receives the event flags. This
           variable can be a combination of the following values:
 
           Value           Meaning
           ─────────────────────────────────────────────────────────────────
           CHAR_RECEIVED   A character has been read from the serial-device
                           receive hardware and placed in the receive
                           queue.
 
           LAST_CHAR_SENT  The last character in the device-driver transmit
                           queue has been sent to the serial-device transmit
                           hardware. This does not mean there is no data to
                           send in any outstanding write requests.
 
           CTS_CHANGED     The clear-to-send (CTS) signal has changed
                           state.
 
           DSR_CHANGED     The data-set-ready (DSR) signal has changed
                           state.
 
           DCD_CHANGED     The data-carrier-detect (DCD) signal has changed
                           state.
 
           BREAK_DETECTED  A break has been detected.
 
           ERROR_OCCURRED  A parity, framing, or overrun error has occurred.
                           An overrun can be a receive hardware overrun or a
                           receive queue overrun.
 
           RI_DETECTED     The trailing edge of the ring indicator (RI) has
                           been detected.
 
hDevice    Identifies the serial device that receives the device-control
           function. The handle must have been created previously by using
           the DosOpen function.
 
Return Value
 
The return value is zero if the function is successful or an error value if
an error occurs.
 
Comments
 
This function clears the event word only when it is successful. The event
word remains unchanged until the device is fully closed (there are no
outstanding open handles) and then reopened.
 
See Also
 
DosOpen, ASYNC_GETCOMMSTATUS, ASYNC_GETCOMMERROR
 
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