mirror of
https://github.com/boostorg/interprocess.git
synced 2026-01-19 04:12:13 +00:00
71 lines
2.2 KiB
C++
71 lines
2.2 KiB
C++
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// (C) Copyright Ion Gaztanaga 2006-2007. 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>
|
|
//[doc_managed_grow
|
|
#include <boost/interprocess/managed_shared_memory.hpp>
|
|
#include <boost/interprocess/managed_mapped_file.hpp>
|
|
#include <cassert>
|
|
|
|
class MyClass
|
|
{
|
|
//...
|
|
};
|
|
|
|
int main()
|
|
{
|
|
using namespace boost::interprocess;
|
|
//Remove shared memory on construction and destruction
|
|
struct shm_destroy
|
|
{
|
|
shm_destroy() { shared_memory_object::remove("MySharedMemory"); }
|
|
~shm_destroy(){ shared_memory_object::remove("MySharedMemory"); }
|
|
} remover;
|
|
|
|
{
|
|
//Create a managed shared memory
|
|
managed_shared_memory shm(create_only, "MySharedMemory", 1000);
|
|
//Check size
|
|
assert(shm.get_size() == 1000);
|
|
//Construct a named object
|
|
MyClass *myclass = shm.construct<MyClass>("MyClass")();
|
|
//The managed segment is unmapped here
|
|
//<-
|
|
(void)myclass;
|
|
//->
|
|
}
|
|
{
|
|
//Now that the segment is not mapped grow it adding extra 500 bytes
|
|
managed_shared_memory::grow("MySharedMemory", 500);
|
|
//Map it again
|
|
managed_shared_memory shm(open_only, "MySharedMemory");
|
|
//Check size
|
|
assert(shm.get_size() == 1500);
|
|
//Check "MyClass" is still there
|
|
MyClass *myclass = shm.find<MyClass>("MyClass").first;
|
|
assert(myclass != 0);
|
|
//The managed segment is unmapped here
|
|
}
|
|
{
|
|
//Now minimize the size of the segment
|
|
managed_shared_memory::shrink_to_fit("MySharedMemory");
|
|
//Map it again
|
|
managed_shared_memory shm(open_only, "MySharedMemory");
|
|
//Check size
|
|
assert(shm.get_size() < 1000);
|
|
//Check "MyClass" is still there
|
|
MyClass *myclass = shm.find<MyClass>("MyClass").first;
|
|
assert(myclass != 0);
|
|
//The managed segment is unmapped here
|
|
}
|
|
return 0;
|
|
}
|
|
//]
|
|
#include <boost/interprocess/detail/config_end.hpp>
|