[Boost-users] Problem with Interprocess Synchronization MUTEX

Subject: [Boost-users] Problem with Interprocess Synchronization MUTEX
From: Daniel Veneros (dann.vd_at_[hidden])
Date: 2010-02-05 10:05:05

Hi,
I have a problem, I need to access a shared memory segment from several
process and all at the same time.
I was looking at boost::interprocess threads but I'm not sure how to
implement the mutex.
this is the code I have(working):

#include <boost/interprocess/managed_shared_memory.hpp>

#include <boost/interprocess/containers/vector.hpp>

#include <boost/interprocess/containers/string.hpp>

#include <boost/interprocess/containers/map.hpp>

#include <boost/interprocess/allocators/allocator.hpp>

#include <cstdlib>

#include <string>

#include <iostream>

#include <map>

#include <sstream>

using namespace boost::interprocess;

typedef managed_shared_memory::segment_manager SegmentManager;

typedef allocator<void, SegmentManager> VoidAllocator;

typedef allocator<char, SegmentManager> CharAllocator;

typedef basic_string<char, std::char_traits<char>, CharAllocator>
BasicString;

class Action

{

    int id;

    BasicString task;

public:

    Action(int num, const char *name, const VoidAllocator &void_alloc)

            :id(num), task(name,void_alloc)

            {}

            void setId(int num);

            void setTask(BasicString newTask);

            int getId();

};

int Action::getId() {

    return id;

}

void Action::setId(int num) {

    id = num;

}

void Action::setTask(BasicString newTask) {

    task = newTask;

}

typedef allocator<Action, SegmentManager> ActionAllocator;

typedef std::pair<const BasicString, Action> MapValueType;

typedef std::pair<BasicString, Action> MovableToMapValueType;

typedef allocator<MapValueType, SegmentManager> MapValueTypeAllocator;

typedef map<BasicString, Action, std::less<BasicString>,
MapValueTypeAllocator> MyMap;

void CreateAndFill() {

    managed_shared_memory segment(create_only, "MySharedMemory", 65536);

    VoidAllocator alloc_inst(segment.get_segment_manager());

   MyMap *myMap = segment.construct<MyMap>("Map"
)(std::less<BasicString>(),alloc_inst);

    std::string keyword;

    std::string helper;

    int i=0;

    for(int adder = 0; adder<=1000; adder++)

    {

        keyword = "Hello";

        std::stringstream out;

        out << adder;

        helper = out.str();

        keyword = keyword + helper;//Creates a string "Hello" + adder

        BasicString key(keyword.c_str(), alloc_inst);//string to BasicString

        Action action(i,"ActionContent", alloc_inst);//puts values of Action
object

        MapValueType value(key, action);

        myMap->insert(value);

        i++;

    }

}

int main(int argc, char** argv) {

    //Remove shared memory on construction and destruction

    struct shm_remove {

        shm_remove() {shared_memory_object::remove("MySharedMemory"); }

        ~shm_remove() {shared_memory_object::remove("MySharedMemory"); }

    }remover;

    CreateAndFill();

}

How and where do I have to set the mutex?? Is this anonymous or named?
Thanks!

Dann