Alias for shared memory ID type.

• huge_pages = SHM_HUGETLB
• huge_2mb = SHM_HUGE_2MB
• huge_1gb = SHM_HUGE_1GB
• no_reserve = SHM_NORESERVE

• create = IPC_CREAT
• exclusive = IPC_EXCL
• no_wait = IPC_NOWAIT

A wrapper for shmid_ds system structure.

Base classes

• public shmid_ds

Types

• using size_type = std::size_t

  Size type. Alias to std::size_t.

• using num_attaches_type = ::shmatt_t

  Return type of num_attaches.

• using tp_type = clock_type::time_point

  Return type of last_attach.

• using clock_type = std::chrono::system_clock

  Clock type used in this class.

Methods

• num_attaches() const -> num_attaches_type

  The current number of attaches.

• last_change() const -> tp_type

  Last change time.

• last_detach() const -> tp_type

  Last detach time.

• last_attach() const -> tp_type

  Last attach time.

• last_user() const -> pid_type

  The last process that accessed this segment.

• creator() const -> pid_type

  The process that created this segment.

• segment_size() const -> size_type

  Size of shared memory segment in bytes.

• shared_memory_segment_status(shm_type id)explicit

  Get status for shared memory segment with ID id.

  bad_call

  
  

  See

  shmctl(2)

A container that stores its elements in shared memory.

• Elements can be accessed in both parent and child processes.
• The container does not provide syncrhonisation.

Types

• using iterator = T *

  Container iterator type.

• using value_type = T

  Container element type.

• using addr_type = void *

  Raw pointer type.

• using size_type = std::size_t

  Size type. Alias to std::size_t.

Fields

• const typedef T * const_iterator

  Container const iterator type.

Methods

• close() -> void

  Detach and remove (if owner) shared memory segment.

  bad_call

  
  

  See

  shmdt(2)

  See

  shmctl(2)

• open_as_owner(mode_type mode, size_type size) -> void

  Create and attach shared memory segment.

  bad_call

  
  

  See

  shmget(2)

  See

  shmat(2)

• open_as_user(shm_type id) -> void

  Attach shared memory segment.

  bad_call

  
  

  See

  shmat(2)

  See

  shmctl(2)

• operator!=(const shared_memory_segment & rhs) const -> bool

  Compare shared memory segments element-wise. ID is not important.

  Return

  false if segments have the same size and the same elements

• operator==(const shared_memory_segment & rhs) const -> bool

  Compare shared memory segments element-wise. ID is not important.

  Return

  true if segments have the same size and the same elements

• operator!() const -> bool

  Checks if the segement is attached.

  Return

  false if the segment is attached

• operator bool() constexplicit

  Checks if the segement is attached.

  Return

  true if the segment is attached

• id() const -> shm_type

  Get segment ID.

• end() const -> const_iterator

  Returns iterator to the end of the container.

• begin() const -> const_iterator

  Returns iterator to the beginning of the container.

• end() -> iterator

  Returns iterator to the end of the container.

• begin() -> iterator

  Returns iterator to the beginning of the container.

• owner() const -> bool

  Check if the segment is owned by this process.

• size_in_bytes() const -> size_type

  Get the size of shared memory segment in bytes.

• size() const -> size_type

  Get the number of elements in the container.

• ptr() const -> addr_type

  Get raw pointer to the contents of shared memory segment.

• ptr() -> addr_type

  Get raw pointer to the contents of shared memory segment.

• swap(shared_memory_segment & rhs) -> void

  Swap with rhs.

• operator=(shared_memory_segment && rhs) -> shared_memory_segment &

  Move-assigment.

• operator=(const shared_memory_segment &) -> shared_memory_segment &
• ~shared_memory_segment()

  Terminates on system error.

• shared_memory_segment(const shared_memory_segment &)
• shared_memory_segment()
• shared_memory_segment(shared_memory_segment && rhs)

  Move-constructor.

• shared_memory_segment(shm_type shm)explicit

  Attach shared memory segment with id shm.

  See

  shmat(2)

• shared_memory_segment(mode_type mode, size_type guaranteed_size)

  Create and attach shared memory segment with mode mode and minimum size guaranteed_size.

  bad_call

  
  

  See

  shmget(2)

  See

  shmat(2)

Overload of std::swap for shared_memory_segment.