Lexmark Printer User Manual page 265

setuserdiskpercent
removes an integer from the stack and discards it.
Errors: stackunderflow, rangecheck, invalidaccess, typecheck
softwareiomode
supports compatibility with the IBM LaserPrinters 4019, 4029, and 4039. It is
parsed and returns a
Software IO mode defines the data stream you are using.
Errors: stackoverflow, stackunderflow
tumble
returns the current value of the Tumble page device parameter.
the back side of the duplexed page prints upside down in relation to
the front side (short-edge binding)
the back side of the duplexed page prints in the same orientation
as the front side (long-edge binding) (default)
Note: No error is generated if a duplex unit is not installed.
This operator is equivalent to executing the following PostScript emulation
sequence:
currentpagedevice /Tumble get
Errors: stackunderflow, stackoverflow
4-60
(zero, Binary Mode Off) on the stack.
PostScript