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// (C) Copyright Ion Gaztanaga 2009. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at
// See for documentation.


#  include <boost/config.hpp>
#  pragma once

#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/detail/workaround.hpp>

#error "This header can't be used in operating systems without XSI (System V) shared memory support"

#include <boost/interprocess/creation_tags.hpp>
#include <boost/interprocess/exceptions.hpp>
#include <boost/interprocess/detail/utilities.hpp>
#include <boost/move/utility_core.hpp>
#include <boost/interprocess/detail/os_file_functions.hpp>
#include <boost/interprocess/interprocess_fwd.hpp>
#include <boost/interprocess/exceptions.hpp>
#include <sys/types.h>
#include <sys/ipc.h>
#include <cstddef>
#include <boost/cstdint.hpp>

//!Describes a class representing a xsi key type.

namespace boost {
namespace interprocess {

//!A class that wraps XSI (System V) key_t type.
//!This type calculates key_t from path and id using ftok,
//!sets key to a specified value,
//!or sets key to IPC_PRIVATE using the default constructor.
class xsi_key

   //!Default constructor.
   //!Represents a private xsi_key.
      : m_key(IPC_PRIVATE)

   //!Creates a new XSI key using a specified value. Constructor is explicit to avoid ambiguity with shmid.
   explicit xsi_key(key_t key)
      : m_key(key)

   //!Creates a new XSI  shared memory with a key obtained from a call to ftok (with path
   //!"path" and id "id"), of size "size" and permissions "perm".
   //!If the shared memory previously exists, throws an error.
   xsi_key(const char *path, boost::uint8_t id)
      key_t key;
         key  = ::ftok(path, id);
         if(((key_t)-1) == key){
            error_info err = system_error_code();
            throw interprocess_exception(err);
         key = IPC_PRIVATE;
      m_key = key;

   //!Returns the internal key_t value
   key_t get_key() const
   {  return m_key;  }

   key_t m_key;

}  //namespace interprocess {
}  //namespace boost {

#include <boost/interprocess/detail/config_end.hpp>