Cannot get I/O permissions
Pei Lin
telent997 at gmail.com
Tue Apr 5 23:30:32 EDT 2011
2011/4/2 Sengottuvelan S <sengottuvelan.s at gmail.com>:
>
> On Fri, Apr 1, 2011 at 3:32 PM, Sengottuvelan S <sengottuvelan.s at gmail.com>
> wrote:
>>
>> Hi All,
>>
>> I am trying to access /dev/mem in my user process. I could not access
Check the kernel config CONFIG_STRICT_DEVMEM
>> because not a privileged access. I tried to use iopl(3) call in linux 2.6,
>> but i am getting unresolved symbol for this. Is any other way to get access
>> in user process. I am not sure how to solve this. Can you someone throw some
>> light on this.
>>
>> if(iopl(3)){
>> fprintf(stderr, "Cannot get I/O permissions (being root helps)");
>> return -1;
>> }
>>
>> if ((fd = open("/dev/mem", O_RDWR | O_SYNC)) < 0) {
>> fprintf(stderr, "Failed to open /dev/mem");
>> return -1;
>> }
>>
>> --
>> Regards,
>> S. Sengottuvelan.
>
>
>
> --
> Regards,
> S. Sengottuvelan.
>
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>
--
Best Regards
Lin
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