PK SAFE ANSI

  Another program included with registration of PKZIP 2 is called
  PKSFANSI.COM.  PKSFANSI is a terminate and stay resident program that
  disables ANSI keyboard key Reassignments, thereby preventing ANSI "bombs"
  embedded in any text file (such as README files) or output by any program.
  Normally, ANSI sequences that redefine the keyboard could be hidden inside
  ANY text file or program, and could be executed completely unnoticed until
  it is too late.  PKSFANSI intercepts calls to the ANSI.SYS or other ANSI
  device drivers, and filters out any keyboard reassignments, while allowing
  other ANSI sequences through unaltered.  If a keyboard reassignment is
  attempted, PKSFANSI will intercept the sequence and discard it.  PKSFANSI
  will also BEEP to alert you that a reassignment was attempted.

  PKSFANSI requires less than 1K bytes resident RAM, and should work with
  any ANSI driver, such as the standard ANSI.SYS driver, NANSI, ZANSI,
  DVANSI, etc.  Note that if you use a memory resident ANSI driver, such as
  the DESQview DVANSI.COM driver, PKSFANSI should be loaded after the ANSI
  driver is loaded.