Hi all,

I'm not proficient at all with ioctl calls in Perl, so maybe someone can enlighten me on this one. Given a kernel module to access a PCI card /dev/pcicard. The following C code is working for writing a value to an internal register of the PCI card. The following code is proven to work:

#include <stdio.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include "pcicard.h"

int main(int argc, char **argv)
{
    u8 val;
    int fd;
    if ((fd = open('/dev/pcicard', O_RDWR)) == -1) {
        perror("open");
        exit(1);
    }
    val = 0x03;
    ioctl(fd, PCICARD_SET_REGISTER, &val);
    close(fd);
    exit(1);
}
[download]

Here's a snipplet from pcicard.h:

#define PCIMAX_IOC_NUM 'O'
#define PCICARD_SET_REGISTER _IOR(PCICARD_IOC_NUM, 1, u8 *)
#define PCICARD_GET_REGISTER _IOW(PCICARD_IOC_NUM, 2, u8 *)
[download]

After converting with h2ph and moving the relevant lines into the Perl script itself, it looks as follows:

#!/usr/bin/perl

require 'sys/ioctl.ph';
require '_h2ph_pre.ph';

sub PCICARD_IOC_NUM () { ord('0'); }
sub PCICARD_SET_REGISTER () { &_IOR( &PCICARD_IOC_NUM, 1, 'int' ); }
sub PCICARD_GET_REGISTER () { &_IOW( &PCICARD_IOC_NUM, 2, 'int' ); }

$value = 0x03;

open(PCI, '+</dev/pcimax');
ioctl(PCI, &PCICARD_SET_REGISTER, \$value);
close(PCI);
[download]

However, this does not work. The corresponding code in the kernel module is not being executed. Any hints what I'm missing here? Many thanks!
Sven

Retitled by davido per consideration vote.

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