IOCTL$ Function
 ----------------------------------------------------------------------------


 Action

 Returns current status information from a device driver.


 Syntax



  IOCTL$(#  filenumber%)

 Remarks


 The argument  filenumber% is the BASIC file number used to open the device.

 The  IOCTL$ function is most frequently used to test whether an  IOCTL
 statement succeeded or failed, or to obtain current status information.

 You can use  IOCTL$ to ask a communications device to return the current
 baud rate, information on the last error, logical line width, and so on. The
 exact information returned depends on the specific device driver. See the
 device driver documentation to find out what status information the device
 driver can send.

 The  IOCTL$ function works only if all of the following conditions are met.

   -         The device driver is installed.

   -         The device driver states that it processes  IOCTL strings. See
             the documentation for the driver.

   -         BASIC performed an  OPEN operation on a file on that device, and
             the file is still open.





 Most standard DOS device drivers do not process  IOCTL strings, and you must
 determine whether the specific driver accepts the command. If the driver
 does not process  IOCTL strings, BASIC generates the error message Illegal
 function call.


 Note

 BASIC devices (LPT n, COM n, SCRN, CONS, PIPE) and DOS block devices (A
 through Z) do not support  IOCTL.

 The  IOCTL statement is not available in OS-2 protected mode. However, you
 can achieve the same effect by directly invoking the DosDevIOCtl OS-2
 functions.


 See Also