ioport(8) — BSD/386 1.0



IOPORT(8)                                               IOPORT(8)


NAME
       ioport - enable or disable user level access to I/O ports

SYNOPSIS
       ioport [-v] -m iobase count
       ioport [-v] -u iobase count

DESCRIPTION
       Ioport  modifies  the  I/O port protection map to allow or
       disallow user level programs access to specific  I/O  port
       address  ranges.   It  is primarily useful in allowing the
       DOS compatibility system to access devices like  the  game
       port (joystick).

       There  are two modes -m (map) and -u (unmap).  With the -m
       argument, ioport will allow user  level  access  to  ports
       starting  at  iobase for a count of count addresses.  When
       the -u argument is specified,  ioport  will  un-map  (deny
       user  level  access)  to the specified range of addresses.
       When the -v argument is supplied, ioport will print a mes-
       sage stating the action it is about to perform.

BUGS
       There  is  no  way to query the map to find out which port
       ranges are currently accessible to user level programs.

HISTORY
       The ioport command first appeared in BSD/386 and  is  cur-
       rently under development.  It may not be present in future
       releases.



























                         December 1, 1992                       1
Museum
