Lexmark T640 - Page 226

PostScript
4-48
userdiskpercent
— userdiskpercent 0
returns a 0 (zero) on the stack.
Errors: stackoverflow, invalidaccess
waittimeout
— waittimeout integer
queries the current value for the WaitTimeout user parameter. An integer is
returned on the stack:
0 disabled
15...65355 seconds
This operator is equivalent to executing the following PostScript emulation
sequence:
currentuserparams /WaitTimeout get
Error: stackoverflow