I'm having a problem with Device::USB, specifically I'm getting the following warning:

Argument "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0..." isn't numeric in subroutine entry at /usr/lib/perl5/site_perl/5.8.8/i386-linux-thread-multi/Device/USB/Device.pm line 585, <DATA> line 1.

This is then followed by a Segmentation fault.

This code from Device::USB that is causing this is: 

sub get_descriptor
{
    my $self = shift;
    my $type = shift;
    my $index = shift;
    $self->_assert_open();

    my $buf = "\0" x MAX_BUFFER_SIZE;

    my $retlen = Device::USB::libusb_get_descriptor(
        $self->{handle}, $type, $index, $buf, MAX_BUFFER_SIZE
    );

    return if $retlen < 0;

    return substr( $buf, 0, $retlen );
}

[download]

The argument $buf ends up as (nil) in Device::USB::libusb_get_descriptor (which is an Inline::C function) so there appears to be some problem with the argument passing.

Is this a bug in the Device::USB package?

Thanks in advance for any advice.

In reply to Problem trying to use Device::USB by scliffe

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