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//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2006-2012. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/libs/interprocess for documentation.
//
//////////////////////////////////////////////////////////////////////////////
//[doc_anonymous_semaphoreB
#include <boost/interprocess/shared_memory_object.hpp>
#include <boost/interprocess/mapped_region.hpp>
#include <iostream>
#include "doc_anonymous_semaphore_shared_data.hpp"
using namespace boost::interprocess;
int main ()
{
//Remove shared memory on destruction
struct shm_remove
{
~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
} remover;
//<-
(void)remover;
//->
//Create a shared memory object.
shared_memory_object shm
(open_only //only open
,"MySharedMemory" //name
,read_write //read-write mode
);
//Map the whole shared memory in this process
mapped_region region
(shm //What to map
,read_write //Map it as read-write
);
//Get the address of the mapped region
void * addr = region.get_address();
//Obtain the shared structure
shared_memory_buffer * data = static_cast<shared_memory_buffer*>(addr);
const int NumMsg = 100;
int extracted_data [NumMsg];
//<-
(void)extracted_data;
//->
//Extract the data
for(int i = 0; i < NumMsg; ++i){
data->nstored.wait();
data->mutex.wait();
extracted_data[i] = data->items[i % shared_memory_buffer::NumItems];
data->mutex.post();
data->nempty.post();
}
return 0;
}
//]
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