in reply to Accessing serial ports under Windows

You probably ought to check the return values of sysread and syswrite. They both return undef on error: 
$result = syswrite(COM, $data);
if (defined $result) {
    print "$result bytes written\n";
} else {
    die "Couldn't write to port.\n";
}

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Of ourse, there's always the CPAN module Win32::SerialPort.

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RE: Re: Accessing serial ports under Windows
by Odud (Pilgrim) on Jun 18, 2000 at 00:00 UTC
    I supposedly searched CPAN this afternoon and found nothing! - in my defence my twin daughters were climbing on me at the time. But you are quite correct I should not assume that the syswrite and sysread are working.
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