如何在boost共享内存中创建多个容器？

可以在共享内存中构造多个对象，如本例所示：

#include <boost/interprocess/managed_shared_memory.hpp>
#include <functional>
#include <iostream>

using namespace boost::interprocess;

void construct_objects(managed_shared_memory &managed_shm)
{
  managed_shm.construct<int>("Integer")(99);
  managed_shm.construct<float>("Float")(3.14);
}

int main()
{
  shared_memory_object::remove("Boost");
  managed_shared_memory managed_shm{open_or_create, "Boost", 1024};
  auto atomic_construct = std::bind(construct_objects,
    std::ref(managed_shm));
  managed_shm.atomic_func(atomic_construct);
  std::cout << *managed_shm.find<int>("Integer").first << '\n';
  std::cout << *managed_shm.find<float>("Float").first << '\n';
}

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您应该使用唯一的名称，也可以使用索引（“数组”）构造样式

有关以下内容，请参阅文档：

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1当然，Coliru不支持SHM。然而，使用映射文件的相同示例：

您应该比“我遇到内存分配问题”更具体。我们现在必须猜测抱歉，我的意思是没有创建instance2和instance3，因为getsegmentmanager获得instance1的相同段管理器，这会抛出一个错误，这只是错误逻辑。分部经理管理分部。它们（显然）可以包含多个对象。（为什么会有名字）连我都这么想。请运行代码并查看。我不明白你为什么看起来这么生气/不耐烦。看看我的Boost进程间答案。我真的不需要运行这个。无论如何，我已经更新了我的答案，包括实时、运行的样本。如果有些东西仍然不起作用，我们应该开始研究Hanks sehe所涉及的环境，但我发布的原因是我想像在代码中那样创建容器，尽管我已经阅读了boost文档，我不明白如何用GetSegmentManager的返回值替换这些参数。在您的理解中，具体的不同点是什么？我已经用实时、运行的示例更新了我的答案，这些示例演示了我的意思。我希望你明白我的意思。啊，是命名引起了这个错误！非常感谢你，sehe:-）它现在起作用了。@Nav我想这是我一直以来回答的第一行：）很高兴它现在起作用了

#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/containers/list.hpp>
#include <boost/interprocess/managed_shared_memory.hpp>
#include <cassert>

typedef boost::interprocess::allocator<int, boost::interprocess::managed_shared_memory::segment_manager>
    ShmemAllocator; // Define an STL compatible allocator of ints that allocates from the managed_shared_memory. This allocator
                    // will allow placing containers in the segment
typedef boost::interprocess::vector<int, ShmemAllocator> MyVector; // Alias a vector that uses the previous STL-like allocator so
                                                                   // that allocates its values from the segment

typedef boost::interprocess::allocator<int, boost::interprocess::managed_shared_memory::segment_manager> ShmemListAllocator;
typedef boost::interprocess::list<int, ShmemListAllocator> MyList;

int main()
{
    // Construct managed shared memory
    std::remove("/dev/shm/MySharedMemory");
    boost::interprocess::managed_shared_memory segment(boost::interprocess::create_only, "MySharedMemory", 65536);

    // const ShmemAllocator alloc_inst(segment.get_segment_manager());
    MyVector *instance  = segment.construct<MyVector>("MyType instance 1")(segment.get_segment_manager());
    MyVector *instance2 = segment.construct<MyVector>("MyType instance 2")(segment.get_segment_manager());
    MyList   *instance3 = segment.construct<MyList>  ("MyList instance")(segment.get_segment_manager());

    assert(instance);
    assert(instance2);
    assert(instance3);

    assert(!std::equal_to<void*>()(instance,  instance2));
    assert(!std::equal_to<void*>()(instance,  instance3));
    assert(!std::equal_to<void*>()(instance2, instance3));
}

//!Allocates and constructs an array of objects of type MyType (throwing version)
//!Each object receives the same parameters (par1, par2, ...)
MyType *ptr = managed_memory_segment.construct<MyType>("Name")[count](par1, par2...);

//!Tries to find a previously created object. If not present, allocates and
//!constructs an array of objects of type MyType (throwing version). Each object
//!receives the same parameters (par1, par2, ...)
MyType *ptr = managed_memory_segment.find_or_construct<MyType>("Name")[count](par1, par2...);

//!Allocates and constructs an array of objects of type MyType (throwing version)
//!Each object receives parameters returned with the expression (*it1++, *it2++,... )
MyType *ptr = managed_memory_segment.construct_it<MyType>("Name")[count](it1, it2...);

#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/containers/list.hpp>
#include <boost/interprocess/managed_shared_memory.hpp>
#include <cassert>

typedef boost::interprocess::allocator<int, boost::interprocess::managed_shared_memory::segment_manager>
    ShmemAllocator; // Define an STL compatible allocator of ints that allocates from the managed_shared_memory. This allocator
                    // will allow placing containers in the segment
typedef boost::interprocess::vector<int, ShmemAllocator> MyVector; // Alias a vector that uses the previous STL-like allocator so
                                                                   // that allocates its values from the segment

typedef boost::interprocess::allocator<int, boost::interprocess::managed_shared_memory::segment_manager> ShmemListAllocator;
typedef boost::interprocess::list<int, ShmemListAllocator> MyList;

int main()
{
    // Construct managed shared memory
    std::remove("/dev/shm/MySharedMemory");
    boost::interprocess::managed_shared_memory segment(boost::interprocess::create_only, "MySharedMemory", 65536);

    // const ShmemAllocator alloc_inst(segment.get_segment_manager());
    MyVector *instance  = segment.construct<MyVector>("MyType instance 1")(segment.get_segment_manager());
    MyVector *instance2 = segment.construct<MyVector>("MyType instance 2")(segment.get_segment_manager());
    MyList   *instance3 = segment.construct<MyList>  ("MyList instance")(segment.get_segment_manager());

    assert(instance);
    assert(instance2);
    assert(instance3);

    assert(!std::equal_to<void*>()(instance,  instance2));
    assert(!std::equal_to<void*>()(instance,  instance3));
    assert(!std::equal_to<void*>()(instance2, instance3));
}