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## Class template basic_managed_external_buffer

boost::interprocess::basic_managed_external_buffer

## Synopsis

    // In header: <boost/interprocess/managed_external_buffer.hpp>

    template<typename CharType, typename AllocationAlgorithm,
             template< class IndexConfig > class IndexType>
    class basic_managed_external_buffer {
    public:
      // types
      typedef base_t::size_type size_type;

      // public member functions
      basic_managed_external_buffer() noexcept;
      basic_managed_external_buffer(open_only_t, void *, size_type);
      basic_managed_external_buffer(basic_managed_external_buffer &&) noexcept;
      basic_managed_external_buffer &
      operator=(basic_managed_external_buffer &&) noexcept;
      void grow(size_type);
      void swap(basic_managed_external_buffer &) noexcept;
    };

## Description

A basic user memory named object creation class. Inherits all basic functionality from basic_managed_memory_impl<CharType, AllocationAlgorithm, IndexType>*<zwj></zwj>/

### `basic_managed_external_buffer` public member functions

1.     basic_managed_external_buffer() noexcept;

   Default constructor. Does nothing. Useful in combination with move semantics

2.     basic_managed_external_buffer(open_only_t, void * addr, size_type size);

   Creates and places the segment manager. This can throw The external memory supplied by the user shall be aligned to the maximum value between `alignof(std::max_align_t)` and the strictest alignment of any over-aligned type to be built !inside that memory. basic_managed_external_buffer (create_only_t, void *addr, size_type size) { Check if alignment is correct BOOST_ASSERT((0 == (((std::size_t)addr) & (AllocationAlgorithm::Alignment - size_type(1u))))); if(!base_t::create_impl(addr, size)){ throw interprocess_exception("Could not initialize buffer in basic_managed_external_buffer constructor"); } }

   !Creates and places the segment manager. This can throw !The external memory supplied by the user shall be aligned to the maximum value between !`alignof(std::max_align_t)` and the strictest alignment of any over-aligned type to be built inside that memory.

3.     basic_managed_external_buffer(basic_managed_external_buffer && moved) noexcept;

   Moves the ownership of "moved"'s managed memory to *this. Does not throw.

4.     basic_managed_external_buffer &
       operator=(basic_managed_external_buffer && moved) noexcept;

   Moves the ownership of "moved"'s managed memory to *this. Does not throw.

5.     void grow(size_type extra_bytes);

   Tries to resize internal heap memory so that we have room for more objects.

6.     void swap(basic_managed_external_buffer & other) noexcept;

   Swaps the ownership of the managed heap memories managed by *this and other. Never throws.