PKUNZIP as an Environment Variable

  PKUNZIP includes the ability to use an environment variable as a
  continuation of the command line.  An option, or number of options may be
  specified by an environment variable.  PKUNZIP will treat the variables as
  if they were passed on the command line.

     example: set PKUNZIP=-)

  This example would disable DPMI usage.

  Note that since the PKUNZIP environment variable is a continuation of the
  command line; it will supersede any preceding option on the command line.