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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_mutexA
#include <boost/interprocess/shared_memory_object.hpp>
#include <boost/interprocess/mapped_region.hpp>
#include <boost/interprocess/sync/scoped_lock.hpp>
#include "doc_anonymous_mutex_shared_data.hpp"
#include <iostream>
#include <cstdio>
using namespace boost::interprocess;
int main ()
{
BOOST_TRY{
//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;
//<-
(void)remover;
//->
//Create a shared memory object.
shared_memory_object shm
(create_only //only create
,"MySharedMemory" //name
,read_write //read-write mode
);
//Set size
shm.truncate(sizeof(shared_memory_log));
//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();
//Construct the shared structure in memory
shared_memory_log * data = new (addr) shared_memory_log;
//Write some logs
for(int i = 0; i < shared_memory_log::NumItems; ++i){
//Lock the mutex
scoped_lock<interprocess_mutex> lock(data->mutex);
std::sprintf(data->items[(data->current_line++) % shared_memory_log::NumItems]
,"%s_%d", "process_a", i);
if(i == (shared_memory_log::NumItems-1))
data->end_a = true;
//Mutex is released here
}
//Wait until the other process ends
while(1){
scoped_lock<interprocess_mutex> lock(data->mutex);
if(data->end_b)
break;
}
}
BOOST_CATCH(interprocess_exception &ex){
std::cout << ex.what() << std::endl;
return 1;
} BOOST_CATCH_END
return 0;
}
//]
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