[rtl] Shared Memory Question

["J.E.Grimm" <jegco@sierra.net>]

Hi...

Regarding the Shared Memory HOWTO discussion, I have found it impossible
to get the:
   ... in an rt-module...
          char *rt_ptr = ADDRESS;

technique to work. It results in a segmentation fault (Unable to handle
paging request...) in all cases.

By using:
          char *rt_ptr;
          rt_ptr = (char *)vremap(ADDRESS,LENGTH);

    ( and the appropriate vfree(rt_ptr) in the cleanup_module func)

everything seems to work as expected.

Has anyone else experienced this problem or am I missing something?
I couldn't find any discussion of the matter in the archives.

The shmex.tgz example showed the same characteristics and similar
changes to that code solved the problem there too.
Tests were run on a 486-33 with 16MB of ram and a P166 with 64MB of ram
using 2.0.30 and 20.0.33 kernels with the same results.

Thanks

Jim...



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