ceph/src/boost/libs/interprocess/example/doc_managed_raw_allocation.cpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 //
   3 // (C) Copyright Ion Gaztanaga 2006-2012. Distributed under the Boost
   4 // Software License, Version 1.0. (See accompanying file
   5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // See http://www.boost.org/libs/interprocess for documentation.
   8 //
   9 //////////////////////////////////////////////////////////////////////////////
  10
  11 //[doc_managed_raw_allocation
  12 #include <boost/interprocess/managed_shared_memory.hpp>
  13 //<-
  14 #include "../test/get_process_id_name.hpp"
  15 //->
  16
  17 int main()
  18 {
  19    using namespace boost::interprocess;
  20
  21    //Remove shared memory on construction and destruction
  22    struct shm_remove
  23    {
  24    //<-
  25    #if 1
  26       shm_remove() { shared_memory_object::remove(test::get_process_id_name()); }
  27       ~shm_remove(){ shared_memory_object::remove(test::get_process_id_name()); }
  28    #else
  29    //->
  30       shm_remove() { shared_memory_object::remove("MySharedMemory"); }
  31       ~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
  32    //<-
  33    #endif
  34    //->
  35    } remover;
  36    //<-
  37    (void)remover;
  38    //->
  39
  40    //Managed memory segment that allocates portions of a shared memory
  41    //segment with the default management algorithm
  42    //<-
  43    #if 1
  44    managed_shared_memory managed_shm(create_only,test::get_process_id_name(), 65536);
  45    #else
  46    //->
  47    managed_shared_memory managed_shm(create_only,"MySharedMemory", 65536);
  48    //<-
  49    #endif
  50    //->
  51
  52    //Allocate 100 bytes of memory from segment, throwing version
  53    void *ptr = managed_shm.allocate(100);
  54
  55    //Deallocate it
  56    managed_shm.deallocate(ptr);
  57
  58    //Non throwing version
  59    ptr = managed_shm.allocate(100, std::nothrow);
  60
  61    //Deallocate it
  62    managed_shm.deallocate(ptr);
  63    return 0;
  64 }
  65 //]
  66