Hi, thanks for all the help, everything is working perfect now. I have another question, I need to access the shared memory segment from several process and all at the same time. I tried to use pthreads but that didn't work. I was looking at boost::interprocess threads but I'm not sure how to implement the mutex. this is the code I have: #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; 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; 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,"Hello", alloc_inst); MapValueType value(key, action); myMap->insert(value); i++; } How do I have to set the mutex?? Thanks! Dann On Wed, Feb 3, 2010 at 11:24 AM, Steven Watanabe <watanabesj@gmail.com>wrote:
AMDG
Daniel Veneros wrote:
Thanks,
I fixed some things and its running now. What I don't know how to do is to declarate/allocate a custom class.. I got this:
typedef managed_shared_memory::segment_manager SegmentManager;
typedef allocator<char, SegmentManager> CharAllocator;
typedef basic_string<char, std::char_traits<char>, CharAllocator> BasicString;
typedef allocator<int, SegmentManager> IntAllocator;
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); };
void Action::setId(int num) { id = num; }
void Action::setTask(BasicString newTask) { task = newTask; }
Now... how should I allocate the "Class" object?? Any Idea? Thanks!!
I assume that by Class you mean the Action class? If this class is used at the top level, you can use managed_shared_memory::construct. If you want to use an allocator with it, the commands are
allocator<Action, SegmentManager> alloc(...); // allocate memory Action* action = alloc.allocate(1); // construct an object using placement new new (action) Action(12, "action", ...);
In Christ, Steven Watanabe
P.S. Please send messages like this to boost-users rather than directly to me.