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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_upgradable_mutexB
#include <boost/interprocess/shared_memory_object.hpp>
#include <boost/interprocess/mapped_region.hpp>
#include <boost/interprocess/sync/scoped_lock.hpp>
#include "doc_upgradable_mutex_shared_data.hpp"
#include <iostream>
#include <cstdio>
using namespace boost::interprocess;
int main ()
{
//Remove shared memory on destruction
struct shm_remove
{
~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
} remover;
//<-
(void)remover;
//->
//Open the shared memory object.
shared_memory_object shm
(open_only //only create
,"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();
//Construct the shared structure in memory
shared_data * data = static_cast<shared_data*>(addr);
//Write some logs
for(int i = 0; i < 100; ++i){
//Lock the upgradable_mutex
scoped_lock<interprocess_upgradable_mutex> lock(data->upgradable_mutex);
std::sprintf(data->items[(data->current_line++) % shared_data::NumItems]
,"%s_%d", "process_a", i);
if(i == (shared_data::NumItems-1))
data->end_b = true;
//Mutex is released here
}
//Wait until the other process ends
while(1){
scoped_lock<interprocess_upgradable_mutex> lock(data->upgradable_mutex);
if(data->end_a)
break;
}
return 0;
}
//]
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