Boost shared memory lockfree circular buffer queue

consumer.cpp

#include <boost/lockfree/spsc_queue.hpp> // ring buffer

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

namespace bip = boost::interprocess;
namespace shm
{
    typedef bip::allocator<char, bip::managed_shared_memory::segment_manager> char_alloc;
    typedef bip::basic_string<char, std::char_traits<char>, char_alloc >      shared_string;

    typedef boost::lockfree::spsc_queue<
        shared_string, 
        boost::lockfree::capacity<200> 
    > ring_buffer;
}

#include <iostream>

int main()
{
    // create segment and corresponding allocator
    bip::managed_shared_memory segment(bip::open_or_create, "MySharedMemory", 65536);
    shm::char_alloc char_alloc(segment.get_segment_manager());

    shm::ring_buffer *queue = segment.find_or_construct<shm::ring_buffer>("queue")();

    while (true)
    {
        shm::shared_string v(char_alloc);
        if (queue->pop(v))
            std::cout << "Processed: '" << v << "'\n";
    }
}

Makefile

all:consumer producer

CPPFLAGS+=-std=c++03 -Wall -pedantic
CPPFLAGS+=-g -O0
CPPFLAGS+=-isystem ~/custom/boost/

LDFLAGS+=-L ~/custom/boost/stage/lib/ -Wl,-rpath,/home/sehe/custom/boost/stage/lib
LDFLAGS+=-lboost_system -lrt -lpthread

%:%.cpp
	$(CXX) $(CPPFLAGS) $^ -o $@ $(LDFLAGS)

producer.cpp

#include <boost/lockfree/spsc_queue.hpp> // ring buffer

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

namespace bip = boost::interprocess;
namespace shm
{
    typedef bip::allocator<char, bip::managed_shared_memory::segment_manager> char_alloc;
    typedef bip::basic_string<char, std::char_traits<char>, char_alloc >      shared_string;

    typedef boost::lockfree::spsc_queue<
        shared_string, 
        boost::lockfree::capacity<200> 
    > ring_buffer;
}

#include <unistd.h>

int main()
{
    // create segment and corresponding allocator
    bip::managed_shared_memory segment(bip::open_or_create, "MySharedMemory", 65536);
    shm::char_alloc char_alloc(segment.get_segment_manager());

    // Ringbuffer fully constructed in shared memory. The element strings are
    // also allocated from the same shared memory segment. This vector can be
    // safely accessed from other processes.
    shm::ring_buffer *queue = segment.find_or_construct<shm::ring_buffer>("queue")();

    const char* messages[] = { "hello world", "the answer is 42", "where is your towel", 0 };

    for (const char** msg_it = messages; *msg_it; ++msg_it)
    {
        sleep(1);
        queue->push(shm::shared_string(*msg_it, char_alloc));
    }
}