Very Computer

Hi,

I have Red Hat 7.2 installed.

I'm trying to develop a program to access a memory area used by other
running process.

I would apreciate some guidelines or book references.

Best regards,

Pedro

AFAIK, you can access "all" of physical memory using the /dev/mem device.
I believe any user can get read privileges but I doubt write unless you're
running as root.  But this is physical memory, not logical memory.  You'd
still have to find some way to map physical addresses back into a user's
virtual address space.

No, it's not easy.  That's intentional.

    Norm

Quote:> Hi,

> I have Red Hat 7.2 installed.

> I'm trying to develop a program to access a memory area used by other
> running process.

> I would apreciate some guidelines or book references.

> Best regards,

> Pedro

Quote:> Hi,

> I have Red Hat 7.2 installed.

> I'm trying to develop a program to access a memory area used by other
> running process.

Are you trying to develop a de*, or just use shared memory?

If two processes are cooperating to share memory, one easy way is to mmap
a shared file (man mmap). They can both map it and it will be shared. You
can also use anonymous shared memory with system V shared memory - I'm
not sure how you do that.

If the other process is not "cooperating", for instance if you want to
hook into it or debug it, and see what's going on, you will need to do
some very system specific stuff.

I believe you should be able to read other processes' memory by reading
/proc/pid/maps and then mmaping bits of /proc/pid/mem into your own
memory space, which will give you read/write access to it. I think this
is how de*s do it.

Cheers
        Mark

Quote:

> Hi,

> I have Red Hat 7.2 installed.

> I'm trying to develop a program to access a memory area used by other
> running process.

> I would apreciate some guidelines or book references.

Have you looked at /proc/*/mem?

Josef
--
Josef M?llers (Pinguinpfleger bei FSC)
        If failure had no penalty success would not be a prize
                                                -- T.  Pratchett

Quote:

> I'm trying to develop a program to access a memory area used by other
> running process.

man shmget

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