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From: sengottuvelan.s@gmail.com (Sengottuvelan S)
To: kernelnewbies@lists.kernelnewbies.org
Subject: i/o opening error for PCI access
Date: Sun, 3 Apr 2011 10:11:22 -0700	[thread overview]
Message-ID: <BANLkTikPRMOXm9BrZfpBcek_NiZe+fYwXQ@mail.gmail.com> (raw)

Hi All,

I am trying to access /dev/mem in my user process. I could not access
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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             reply	other threads:[~2011-04-03 17:11 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-04-03 17:11 Sengottuvelan S [this message]
2011-04-03 22:47 ` i/o opening error for PCI access Prasad Joshi
2011-04-04  0:19   ` Sengottuvelan S
2011-04-04  6:25     ` Mulyadi Santosa

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