This is Sys::PortIO, a Perl interface to direct port I/O functions
(on Unix-like systems, inb() and outb() and friends).
You can install it in the typical CPAN module manner:

    % perl Makefile.PL
    % make
    % make test
    # make install

You can find the latest distribution at the following URL:

    http://www.zeuscat.com/andrew/src/Sys-PortIO-0.1.tar.gz

You can also find it at your friendly neighborhood CPAN:

    http://www.perl.com/CPAN-local/modules/by-module/Sys/

Appended below is are the Changes and POD documentation from PortIO.pm.

Contact Andrew Ho (andrew@zeuscat.com) with comments or bug reports.


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Revision history for Perl extension Sys::PortIO.

0.1 - March 4, 2005

  * Original version, created by Andrew Ho (andrew@zeuscat.com), rolled.


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NAME

    Sys::PortIO - perform direct port I/O from Perl

SYNOPSIS

        use Sys::PortIO;

        port_open($portnum);
        write_byte($portnum, $value);
        $value = read_byte($portnum);
        port_close($portnum);

DESCRIPTION

    This module provides a Perl interface to the low-level port I/O
    operations provided by Linux, FreeBSD, or OpenBSD. Among other things,
    this is useful for writing Perl scripts that interface with parallel,
    serial, or joystick ports.

BUGS

    On some systems (for example, Linux), doing a port read or write on an
    unopened port will cause a segmentation fault.

TODO

    Support optional range argument to "port_open()".
    Set $! on errors, instead of dying (sometimes with a segfault).
    Alternately, automatically open ports as needed.

SEE ALSO

    Linux I/O port mini-HOWTO:
    <http://www.faqs.org/docs/Linux-mini/IO-Port-Programming.html>

    On Linux or other glibc systems, see ioperm(2), inb(2), and outb(2).
    FreeBSD uses /dev/io for port access. On OpenBSD and NetBSD, see
    i386_iopl(2) and sysarch(2).

AUTHOR

    Andrew Ho, <andrew@zeuscat.com>

COPYRIGHT AND LICENSE

    Copyright (C) 2005 by Andrew Ho.

    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself, either Perl version 5.6.0 or, at
    your option, any later version of Perl 5 you may have available.