Tandy 1000 Basic Reference Manual page 191

Chapter
10 I
BASIC
Keywords
IOCTL$ Advanced Function
IOCTL$([#lbuf,r)
Returns the control data string from a device driver that you
have opened previously.
Buffer is the number assigned to the driver when you opened it.
The number sign
(#)
is optional. It is provided for compatibility
with other BASICs.
You can use the IOCTL$ function to confirm that a IOCTL
statement succeeded (or failed). You can also use IOCTL$ to get
information from the device.
For more information on device drivers, see the Programmer's
Reference manual for your computer. It
is
available a t your Radio
Shack Computer Store.
Example
1 0 OPEN " \ D E V \ P R N "
FIS
1
2 0 I F I O C T L $ C I )
=
"NR" THEN P R I N T " P R I N T E R NOT
REFIDY"
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