boost managed_shared_memory find（）方法永远卡在互斥锁上

我有以下程序，这是它应该做的：

• 打开/创建共享内存段
• 对该托管共享内存段调用find（）以查找对象
• 如果未找到，请实例化它
• 如果找到，只需转储内容

我用以下方法测试它：

• 在一个窗口中运行此程序的一个实例
• 它创建共享mem段，并实例化对象
• 永远等待（不确定是否需要，只是添加了它以确保linux不会在程序退出时释放共享内存）
• 运行同一程序的另一个实例，并期望它找到对象（这就是它卡住的地方）

  类数据存储{
  公众：
  数据存储（uint32\t id，常量字符*名称，布尔安全）{
  id＝id；
  strncpy（名称、名称、尺寸（名称））；
  安全=安全；
  }
  ~data_store（）{}
  uint32_t id（void）const{return id_；}
  const char*name（void）const{返回名称}
  私人：
  字符名_u32]；
  布尔安全；
  uint32\u t id\u；
  };
  int
  主要（）
  {
  托管共享内存*test\u shmseg；
  数据存储*ds；
  试一试{
  test_shmseg=新的受管共享内存（打开或创建“seg2”，2048）；
  }捕获（std:：exception ex）{
  标准：cerr
  
  永远等待（不确定是否需要，只是添加了它以确保linux不会在程序退出时释放共享内存）
  
  不，这不是必需的。共享内存是共享的。除非您显式地
  remove（）
  It，否则它将保留
  
  复习
  您至少有一个不一致：对象的名称是
  “Datastore”
  或
  “Datastore”
  -请确保拼写匹配
  
  除此之外，我认为
  
  
  您可能不希望使用（无意中？）正在使用的“数组样式”分配
  您最好使用
  find_或_-construct
  ，这样可以消除潜在的竞争条件（分别在查找和创建新实例之间的检查时间与使用时间窗口）
  
  除此之外，我看不出挂起的直接原因。也许您可以尝试手动删除共享对象一次，然后使用以下简化程序重新测试：
  
  #include <boost/interprocess/managed_shared_memory.hpp>
  #include <iostream>
  #include <cassert>
  namespace bip = boost::interprocess;
  
  class data_store {
    public:
      data_store(uint32_t id, const char *name, bool safe) :
          id_(id), safe_(safe)
      {
          id_ = id;
          assert(name && strlen(name) < (sizeof(name_)-1));
          strncpy(name_, name, sizeof(name_));
          safe_ = safe;
      }
  
      uint32_t   id()    const { return id_; }
      const char *name() const { return name_; }
  
    private:
      char name_[32] = {0};
      uint32_t id_;
      bool safe_;
  };
  
  int main () try {
      bip::managed_shared_memory seg(bip::open_or_create, "seg2", 2048);
      data_store ds = *seg.find_or_construct<data_store>("DataStore")(1, "ds", true);
      std::cout << "Free size " << seg.get_free_memory() << std::endl;    
      std::cout << "Data store name " << ds.name() << std::endl;
  } catch (std::exception ex) {
      std::cerr << ex.what() << '\n';
  }
  
  谢谢..这很有效..我删除了现有的段，并将对象的名称固定在数据存储/数据存储之间，使其与工作状态一致。如果对象不存在，我希望不会像那样被卡住。如果删除段是关键步骤，则可能意味着进程因嵌入互斥锁而崩溃ed.没有真正的（便携式）解决方案：
  (gdb) bt
  #0  0x00007ffff7bcd42d in __lll_lock_wait () from /lib64/libpthread.so.0
  #1  0x00007ffff7bc8de6 in _L_lock_870 () from /lib64/libpthread.so.0
  #2  0x00007ffff7bc8cdf in pthread_mutex_lock () from /lib64/libpthread.so.0
  #3  0x0000000000403d6d in boost::interprocess::ipcdetail::posix_recursive_mutex::lock (this=0x7ffff7ff8070)
      at /usr/include/boost/interprocess/sync/posix/recursive_mutex.hpp:90
  #4  0x0000000000403e52 in boost::interprocess::interprocess_recursive_mutex::lock (this=0x7ffff7ff8070)
      at /usr/include/boost/interprocess/sync/interprocess_recursive_mutex.hpp:163
  #5  0x0000000000408457 in boost::interprocess::scoped_lock<boost::interprocess::interprocess_recursive_mutex>::lock
      (this=0x7fffffffdf30) at /usr/include/boost/interprocess/sync/scoped_lock.hpp:284
  #6  0x00000000004073b0 in boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void, long, unsigned long, 0ul>, 0ul>, boost::interprocess::iset_index>::priv_get_lock (this=0x7ffff7ff8010, use_lock=true)
      at /usr/include/boost/interprocess/segment_manager.hpp:1315
  #7  0x00000000004069ea in boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void, long, unsigned long, 0ul>, 0ul>, boost::interprocess::iset_index>::priv_generic_find<char> (this=0x7ffff7ff8010, name=0x41c4a5 "Datastore", index=..., table=...,
      length=@0x7fffffffe098: 0, is_intrusive=..., use_lock=true)
      at /usr/include/boost/interprocess/segment_manager.hpp:844
  #8  0x0000000000405f1e in boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void, long, unsigned long, 0ul>, 0ul>, boost::interprocess::iset_index>::priv_find_impl<data_store> (this=0x7ffff7ff8010, name=0x41c4a5 "Datastore", lock=true)
      at /usr/include/boost/interprocess/segment_manager.hpp:724
  #9  0x0000000000405309 in boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void, long, unsigned long, 0ul>, 0ul>, boost::interprocess::iset_index>::find<data_store> (this=0x7ffff7ff8010, name=...)
      at /usr/include/boost/interprocess/segment_manager.hpp:434
  #10 0x00000000004044ea in boost::interprocess::ipcdetail::basic_managed_memory_impl<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void, long, unsigned long, 0ul>, 0ul>, boost::interprocess::iset_index, 16ul>::find<data_store> (this=0x63ec20, name=...)
      at /usr/include/boost/interprocess/detail/managed_memory_impl.hpp:346
  #11 0x00000000004040f7 in boost::interprocess::basic_managed_shared_memory<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void, long, unsigned long, 0ul>, 0ul>, boost::int---Type <return> to continue, or q <return> to quit---
  erprocess::iset_index>::find<data_store> (this=0x63ec20, name=...)
      at /usr/include/boost/interprocess/managed_shared_memory.hpp:212
  
  #include <boost/interprocess/managed_shared_memory.hpp>
  #include <iostream>
  #include <cassert>
  namespace bip = boost::interprocess;
  
  class data_store {
    public:
      data_store(uint32_t id, const char *name, bool safe) :
          id_(id), safe_(safe)
      {
          id_ = id;
          assert(name && strlen(name) < (sizeof(name_)-1));
          strncpy(name_, name, sizeof(name_));
          safe_ = safe;
      }
  
      uint32_t   id()    const { return id_; }
      const char *name() const { return name_; }
  
    private:
      char name_[32] = {0};
      uint32_t id_;
      bool safe_;
  };
  
  int main () try {
      bip::managed_shared_memory seg(bip::open_or_create, "seg2", 2048);
      data_store ds = *seg.find_or_construct<data_store>("DataStore")(1, "ds", true);
      std::cout << "Free size " << seg.get_free_memory() << std::endl;    
      std::cout << "Data store name " << ds.name() << std::endl;
  } catch (std::exception ex) {
      std::cerr << ex.what() << '\n';
  }
  
  Free size 1712
  Data store name ds
  -rw-r--r-- 1 2001 2000 2.0K Mar  5 12:26 seg2
  Free size 1712
  Data store name ds