| Home | Libraries | People | FAQ | More

## Class file_mapping

boost::interprocess::file_mapping

## Synopsis

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

    class file_mapping {
    public:
      // construct/copy/destruct
      file_mapping();
      file_mapping(const char *, mode_t);
      file_mapping(file_mapping &&);
      file_mapping& operator=(file_mapping &&);
      ~file_mapping();

      // public member functions
      void swap(file_mapping &&) ;
      mode_t get_mode() const;
      mapping_handle_t get_mapping_handle() const;
      const char * get_name() const;
    };

## Description

A class that wraps a file-mapping that can be used to create mapped regions from the mapped files

### `file_mapping` public construct/copy/destruct

1.     file_mapping();

   Constructs an empty file mapping. Does not throw

2.     file_mapping(const char * filename, mode_t mode);

   Opens a file mapping of file "filename", starting in offset "file_offset", and the mapping's size will be "size". The mapping can be opened for read-only "read_only" or read-write "read_write" modes. Throws interprocess_exception on error.

3.     file_mapping(file_mapping && moved);

   Moves the ownership of "moved"'s file mapping object to *this. After the call, "moved" does not represent any file mapping object. Does not throw

4.     file_mapping& operator=(file_mapping && moved);

   Moves the ownership of "moved"'s file mapping to *this. After the call, "moved" does not represent any file mapping. Does not throw

5.     ~file_mapping();

   Destroys the file mapping. All mapped regions created from this are still valid. Does not throw

### `file_mapping` public member functions

1.     void swap(file_mapping && other) ;

   Swaps to file_mappings. Does not throw.

2.     mode_t get_mode() const;

   Returns access mode used in the constructor

3.     mapping_handle_t get_mapping_handle() const;

   Obtains the mapping handle to be used with mapped_region

4.     const char * get_name() const;

   Returns the name of the file used in the constructor.