Re: [Boost-users] [interprocess] Shared memory compile problem

Subject: Re: [Boost-users] [interprocess] Shared memory compile problem
From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2009-04-21 12:54:24

Po-Chun wrote:
> I am a new user and try to write some codes with shared memory using
> boost.interprocess.
> Basically, I followed the examples and the allocation seems fine. But
> the use of shared-memory container gave me a bunch of error messages
> related to
> "instantiated from here." during compile. The error seems related to
> the template.
> But I have no idea how to fix it yet. Any suggestion would be helpful.
> Thanks.

set's constructor is equal to std::constructor, but you must pay more 
attention because it needs an allocator and set's constructor taking the 
allocator takes also the comparison option. You have several C++ errors 
in your code (set's template arguments are not correct, for example).

This should compile fine:

#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/containers/set.hpp>
#include <boost/cstdint.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
#include <functional>
#include <utility>

struct LongIntLess
{
    bool operator()(const boost::uint64_t a, const boost::uint64_t b) const
    {
      return a < b;
    }
};

int main ()
{
    using namespace boost::interprocess;
    try{
       shared_memory_object::remove("SharedMemory");
       managed_shared_memory segment
          (create_only, "SharedMemory", sizeof(boost::uint64_t)*200);

       typedef allocator< boost::uint64_t,
                         managed_shared_memory::segment_manager>
       shmAllocator_t;

       typedef set<boost::uint64_t, LongIntLess, shmAllocator_t> shrSet_t;

       const shmAllocator_t alloc_inst (segment.get_segment_manager());
       shrSet_t  *WrSet_1;
       WrSet_1 = segment.construct<shrSet_t> ("shrSet_t")
          (LongIntLess(), alloc_inst);

       WrSet_1->insert(2);
    } catch (...){
       shared_memory_object::remove("SharedMemory");
       throw;
    }
    shared_memory_object::remove("SharedMemory");
}

Ion