[Boost-users] boost::interprocess container of pointers

Subject: [Boost-users] boost::interprocess container of pointers
From: Mateusz Ziobro (mateusz.ziobro_at_[hidden])
Date: 2009-11-22 05:59:03

Hi,
I have a problem with container of pointers in shared memory using 
boost::interprocess,
object created by construct method is mapped to local memory address, so 
I can not just put it into
shared memory container because the address would be invalid in other 
process,
probably I have to remap or use some kind of smart pointer and than put 
into container.
My question is Does someone know how to do that? Please see following 
piece of code.

#include <iostream>
#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
#include <boost/interprocess/containers/set.hpp>

class TestData
{
  int value_;

public:
  TestData(int value): value_(value) { }
  int get_value() const { return value_; }
};

int main(int argc)
{
  using namespace boost::interprocess;

  managed_shared_memory mgr(open_or_create, "shm_test", 1024*1024);
  TestData* t1 = mgr.construct<TestData>("test_data")(99);

  std::cout << t1->get_value() << std::endl;

  //TestData* is address in local memory
  //we can not keep those addresses in shared memory set, would be 
invalid in other process
  //typedef allocator<const TestData*, 
managed_shared_memory::segment_manager> allocator;
  //typedef set<const TestData*, std::less<TestData*>, allocator> 
TestDataSet;
  //TestDataSet* s1 = 
mgr.construct<TestDataSet>("test_data_set")(std::less<TestData*>(),
  //                                                                     
                     mgr.get_segment_manager());
}