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Re: Unable to open /dev/mem: permission denied

On Apr 15 03:15, Brian Dessent wrote:
> Jamie Mortimore wrote:
> > Unable to open /dev/mem: Permission denied
> > 
> > I have set up a root user (in /etc/passwd) and am running the program
> > as root but this doesn't solve the problem. Any help much appreciated.
> Having a user named 'root' in passwd is irrelevant.  What matters is
> whether you are logged in to Windows with a user account that has
> Administrator privileges.  Is that what you mean by "running the program
> as root"?
> To be clear, it doesn't matter at all what you name the user or what you
> put in /etc/passwd or /etc/group, what matters is whether Windows
> considers the user to have admin privileges, as the return value of
> open("/dev/mem") is just a direct translation of the result of calling
> the NT function to open \device\physicalmemory, so it's up to Windows
> whether this fails or succeeds, not anything in Cygwin.

Funny(*) sidenote:  Accessing \device\physicalmemory from privileged
user mode processes works only on NT4, W2K and XP.  Starting with 2K3,
access to physical memory has been restricted to work only in kernel


(*) No, not really.

Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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