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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.
//
//////////////////////////////////////////////////////////////////////////////
#include <boost/interprocess/detail/workaround.hpp>
//[doc_move_containers
#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/containers/string.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
#include <cassert>
//<-
#include "../test/get_process_id_name.hpp"
//->
int main ()
{
using namespace boost::interprocess;
//Typedefs
typedef managed_shared_memory::segment_manager SegmentManager;
typedef allocator<char, SegmentManager> CharAllocator;
typedef basic_string<char, std::char_traits<char>
,CharAllocator> MyShmString;
typedef allocator<MyShmString, SegmentManager> StringAllocator;
typedef vector<MyShmString, StringAllocator> MyShmStringVector;
//Remove shared memory on construction and destruction
struct shm_remove
{
//<-
#if 1
shm_remove() { shared_memory_object::remove(test::get_process_id_name()); }
~shm_remove(){ shared_memory_object::remove(test::get_process_id_name()); }
#else
//->
shm_remove() { shared_memory_object::remove("MySharedMemory"); }
~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
//<-
#endif
//->
} remover;
//<-
(void)remover;
//->
//<-
#if 1
managed_shared_memory shm(create_only, test::get_process_id_name(), 65536);
#else
//->
managed_shared_memory shm(create_only, "MySharedMemory", 10000);
//<-
#endif
//->
//Create allocators
CharAllocator charallocator (shm.get_segment_manager());
StringAllocator stringallocator(shm.get_segment_manager());
//Create a vector of strings in shared memory.
MyShmStringVector *myshmvector =
shm.construct<MyShmStringVector>("myshmvector")(stringallocator);
//Insert 50 strings in shared memory. The strings will be allocated
//only once and no string copy-constructor will be called when inserting
//strings, leading to a great performance.
MyShmString string_to_compare(charallocator);
string_to_compare = "this is a long, long, long, long, long, long, string...";
myshmvector->reserve(50);
for(int i = 0; i < 50; ++i){
MyShmString move_me(string_to_compare);
//In the following line, no string copy-constructor will be called.
//"move_me"'s contents will be transferred to the string created in
//the vector
myshmvector->push_back(boost::move(move_me));
//The source string is in default constructed state
assert(move_me.empty());
//The newly created string will be equal to the "move_me"'s old contents
assert(myshmvector->back() == string_to_compare);
}
//Now erase a string...
myshmvector->pop_back();
//...And insert one in the first position.
//No string copy-constructor or assignments will be called, but
//move constructors and move-assignments. No memory allocation
//function will be called in this operations!!
myshmvector->insert(myshmvector->begin(), boost::move(string_to_compare));
//Destroy vector. This will free all strings that the vector contains
shm.destroy_ptr(myshmvector);
return 0;
}
//]
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