ioctl12.hlp (Topic list)
Important Notice
The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.
ASYNC_GETCOMMERROR (1.2)
                                                      Up Next Previous
────────────────────────────────────────────────────────────────────────────
 
#define INCL_DOSDEVIOCTL
 
USHORT DosDevIOCtl(pfCommErr, 0L, 0x006D, 0x0001, hDevice)
PUSHORT pfCommErr;    /* pointer to variable for error */
HFILE hDevice;        /* device handle                 */
 
The ASYNC_GETCOMMERROR function retrieves the communication error word.
After copying the error-word value to the specified variable, the function
clears the error word.
 
Parameter  Description
────────────────────────────────────────────────────────────────────────────
 
pfCommErr  Points to the variable that receives the communication status of
           the device. This variable can be a combination of the following
           values:
 
           Value                Meaning
           ─────────────────────────────────────────────────────────────────
           RX_QUE_OVERRUN       Receive-queue overrun. There is no room in
                                the device-driver receive queue to put a
                                character read in from the receive
                                hardware.
 
           RX_HARDWARE_OVERRUN  Receive-hardware overrun. A character
                                arrived before the previous character was
                                completely read. The previous character is
                                lost.
 
           PARITY_ERROR         The hardware detected a parity error.
 
           FRAMING_ERROR        The hardware detected a framing error.
 
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. When an error
occurs, the function returns an error value, and any value copied to the
variable pointed to by the pfCommErr parameter is not valid, and the
function does not clear the error word.
 
Comments
 
Other than using this function, the only way to clear the communications
error word for a device is to open the device when there are no outstanding
open handles for it. For more information, see the ASYNC_SETDCBINFO function
(0x0001, 0x0053).
 
See Also
 
DosOpen, ASYNC_GETCOMMEVENT, ASYNC_GETCOMMSTATUS, ASYNC_SETDCBINFO
 
                                      ♦