interprocess/example/doc_spawn_vector.cpp
2014-10-13 23:26:57 +02:00

114 lines
3.5 KiB
C++

//////////////////////////////////////////////////////////////////////////////
//
// (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/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
//[doc_spawn_vector
#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
#include <string>
#include <cstdlib> //std::system
//<-
#include "../test/get_process_id_name.hpp"
//->
using namespace boost::interprocess;
//Define an STL compatible allocator of ints that allocates from the managed_shared_memory.
//This allocator will allow placing containers in the segment
typedef allocator<int, managed_shared_memory::segment_manager> ShmemAllocator;
//Alias a vector that uses the previous STL-like allocator so that allocates
//its values from the segment
typedef vector<int, ShmemAllocator> MyVector;
//Main function. For parent process argc == 1, for child process argc == 2
int main(int argc, char *argv[])
{
if(argc == 1){ //Parent process
//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;
//->
//Create a new segment with given name and size
//<-
#if 1
managed_shared_memory segment(create_only, test::get_process_id_name(), 65536);
#else
//->
managed_shared_memory segment(create_only, "MySharedMemory", 65536);
//<-
#endif
//->
//Initialize shared memory STL-compatible allocator
const ShmemAllocator alloc_inst (segment.get_segment_manager());
//Construct a vector named "MyVector" in shared memory with argument alloc_inst
MyVector *myvector = segment.construct<MyVector>("MyVector")(alloc_inst);
for(int i = 0; i < 100; ++i) //Insert data in the vector
myvector->push_back(i);
//Launch child process
std::string s(argv[0]); s += " child ";
//<-
s += test::get_process_id_name();
//->
if(0 != std::system(s.c_str()))
return 1;
//Check child has destroyed the vector
if(segment.find<MyVector>("MyVector").first)
return 1;
}
else{ //Child process
//Open the managed segment
//<-
#if 1
managed_shared_memory segment(open_only, argv[2]);
#else
//->
managed_shared_memory segment(open_only, "MySharedMemory");
//<-
#endif
//->
//Find the vector using the c-string name
MyVector *myvector = segment.find<MyVector>("MyVector").first;
//Use vector in reverse order
std::sort(myvector->rbegin(), myvector->rend());
//When done, destroy the vector from the segment
segment.destroy<MyVector>("MyVector");
}
return 0;
}
//]
#include <boost/interprocess/detail/config_end.hpp>