On 2012-03-21 12:31, Rajalakshmi Iyer wrote:
Hello,
I want to be able to store a hash map (apr_hash_t) in the Apache shared
memory (created using apr_shm_create). This map will be created once and
will be shared by all child processes.
However, when I try to access the hash stored in the shared memory, I get a
segmentation fault (because the hash appears empty).
I have ensured that I use the apr_shm_baseaddr_get to get the starting
address for the map in shared memory correctly.
However that does not seem to help.
Note that I have tried the same code with simple data structures like char*
etc and it works. Do I need to do something more to get a hash into and out
of the shared memory?
Thanks in advance!
I don't think you can put it into shared memory. It uses an apr_pool in
order to allocate new data when you add elements to the hash. The
apr_pool will allocate non-shared memory.
If your code is C++ or can be migrated to C++, have a look here:
http://www.boost.org/doc/libs/1_49_0/doc/html/interprocess/allocators_containers.html#interprocess.allocators_containers.containers_explained
Sorin
