Alain Rolle wrote:
>
> Hi,
>
> For weeks now I've been trying to implement shared memory with Linux
> 2.0.36 and rtl 1.1, and I finally got there.Therefore however, I needed
> to use the next mmap formulation :
>
> shm = (shm_t *) mmap(BASE_ADDRESS,sizeof(shm_t),PROT_READ | PROT_WRITE,
> MAP_FIXED | MAP_PRIVATE,fd,0);
>
> That is, as you know, different from the statement in the Shared Memory
> HOWTO (where mmap works with MAP_FILE | MAP_SHARED ). I want to stress
> that this really didn't work, and though I'm happy it works now, I would
> like to know whether I can expect problems later on due to these
> differences. Can anyone give me advice in that direction ?
>
Hi Alain,
I think the reason is the last argument (the shared memory base addr) is
zero in your example. Normally using this method, it would be a high
address beyond the end of the RAM that Linux knows about.
Although you have got this to work, using this low address will probably
cause you grief as it is within the range Linux knows about (0xA0000
0xFFFFF is reserved for adapter memory and not used by linux).
Regards,
Stuart
--- [rtl] ---
To unsubscribe:
echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR
echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED]
----
For more information on Real-Time Linux see:
http://www.rtlinux.org/~rtlinux/
