Question

我知道boost interprocess containers，示例使用托管共享内存。但我想使用一个简单的boost::interprocess::shared_memory_object，其中有一个对象，以及该对象中的向量或任何其他容器。这似乎不起作用。

试过这个：

#include <stack>
#include <boost/interprocess/containers/vector.hpp>

namespace bip = boost::interprocess;

class SharedMemoryMetadata
{
public:
    std::stack<unsigned short> newData;
    int deleteme;
    bip::vector<unsigned short> v;
};

并使用以下命令创建共享内存：

bip::shared_memory_object::remove(OUTPUT_METADATA_MEMORY_SEGMENT_NAME);
sharedMemoryMetadataForOutput = new bip::shared_memory_object(bip::create_only, OUTPUT_METADATA_MEMORY_SEGMENT_NAME, bip::read_write);//use old shared memory if exists else create a new one
sharedMemoryMetadataForOutput->truncate(sizeof(SharedMemoryMetadata)+ (3*sizeof(unsigned int)*MAX_NUMBER_OF_OBJECTS_EXPECTED_TO_BE_IN_SHARED_MEMORY));//set the size of the memory object
sharedMemoryMetadataRegion = new bip::mapped_region(*sharedMemoryMetadataForOutput, bip::read_write);//map the whole shared memory in this process
void* sharedMemorySegmentForMetadataStorage = sharedMemoryMetadataRegion->get_address();//get the region address
sharedMemoryMetadataObject = new (sharedMemorySegmentForMetadataStorage) SharedMemoryMetadata();//create a shared memory buffer in memory

我尝试使用以下方式访问它：

bip::shared_memory_object* sharedMemoryMetadataForOutput;
SharedMemoryMetadata* sharedMemoryMetadataObject;
bip::mapped_region* sharedMemoryMetadataRegion;

bip::shared_memory_object* sharedMemoryMetadataForOutput;
SharedMemoryMetadata* sharedMemoryMetadataObject;
bip::mapped_region* sharedMemoryMetadataRegion;  
sharedMemoryMetadataForOutput = new bip::shared_memory_object(bip::open_only, OUTPUT_METADATA_MEMORY_SEGMENT_NAME, bip::read_write);//create a shared memory object http://blog.wolfgang-vogl.com/?p=528
sharedMemoryMetadataRegion = new bip::mapped_region(*sharedMemoryMetadataForOutput, bip::read_write);//Map the whole shared memory in this process        
void * sharedMemorySegmentForMetadataStorage = sharedMemoryMetadataRegion->get_address();//get the region address
sharedMemoryMetadataObject = static_cast<SharedMemoryMetadata*>(sharedMemorySegmentForMetadataStorage);//Obtain the shared structure

正如预期的那样，即使写入堆栈的内容，std::stack<unsigned short> newData;也是空的。但是如果我为int deleteme分配一个值，我就能从另一个访问共享内存的程序中读取它。

push_back到bip::vector<unsigned short> v;有效，但是当我尝试从其他程序访问它时，我遇到了分段错误。有没有办法可以在shared_memory_object中存储和访问向量，或者只使用托管共享内存？即使我使用托管共享内存，如何将向量存储在SharedMemoryMetadata类中，如上所示？

在boost进程中存储向量或任何其他容器shared_memory_object？

0 个答案: