[Boost-bugs] [Boost C++ Libraries] #4066: Boost::Interprocess::vector only pushes back so many correct values before it always pushes 0.

Subject: [Boost-bugs] [Boost C++ Libraries] #4066: Boost::Interprocess::vector only pushes back so many correct values before it always pushes 0.
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-04-05 06:31:38

#4066: Boost::Interprocess::vector only pushes back so many correct values before
it always pushes 0.
--------------------------------------+-------------------------------------
 Reporter:  powerking89670@…          |       Owner:  igaztanaga  
     Type:  Bugs                      |      Status:  new         
Milestone:  Boost 1.43.0              |   Component:  interprocess
  Version:  Boost 1.42.0              |    Severity:  Problem     
 Keywords:                            |  
--------------------------------------+-------------------------------------
 I was perusing the documentation on interprocess, and I decided to scale
 up the example a bit to make sure it would suit my purposes.

 {{{
 #include <conio.h> //For getch
 #include <boost/interprocess/managed_shared_memory.hpp>
 #include <boost/interprocess/containers/vector.hpp>
 #include <boost/interprocess/allocators/allocator.hpp>
 #include <boost/thread.hpp>
 #include <stdio.h>

 using namespace boost::interprocess;

 //Define an STL compatible allocator of ints that allocates from the
 managed_shared_memory.
 //This allocator will allow placing containers in the segment
 typedef allocator<int, managed_shared_memory::segment_manager>
 ShmemAllocator;

 //Alias a vector that uses the previous STL-like allocator so that
 allocates
 //its values from the segment
 typedef boost::interprocess::vector<int, ShmemAllocator> MyVector;

 int main(int argc, char* argv[])
 {
         struct shm_remove
      {
          shm_remove() { shared_memory_object::remove("MySharedMemory"); }
          ~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
       } remover;

       //Create a new segment with given name and size
       managed_shared_memory segment(create_only, "MySharedMemory", 80000);

       //Initialize shared memory STL-compatible allocator
       const ShmemAllocator alloc_inst (segment.get_segment_manager());

       //Construct a vector named "MyVector" in shared memory with argument
 alloc_inst
       MyVector *myvector =
 segment.construct<MyVector>("MyVector")(alloc_inst);

                 myvector->reserve(5000);

       for(int i = 0; i < 5000; i++)  //Insert data in the vector
          myvector->push_back(5);

              for(unsigned int i=0; i < myvector->size(); i++)
                 {
                         printf("%u: %u\n", i+1, myvector[i]);
                 }



    _getch();
    return 0;
 }
 }}}

 However, when this code is build/run it outputs the correct value for a
 while and then suddenly the values switch to 0 or vary widely.

 Am I doing something incorrectly, or is this a problem with the lib?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4066>
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