Linux Manuals

std::pmr::synchronized_pool_resource – std::pmr::synchronized_pool_resource Synopsis Defined in header <memory_resource> class synchronized_pool_resource : public std::pmr::memory_resource; (since C++17) The class std::pmr::synchronized_pool_resource is a general-purpose memory resource class with the following properties: * It owns the allocated memory and frees it on destruction, even if deallocate has not been called for some of the allocated blocks. * It consists…

std::pmr::set_default_resource – std::pmr::set_default_resource Synopsis Defined in header <memory_resource> std::pmr::memory_resource* set_default_resource(std::pmr::memory_resource* r) noexcept; (since C++17) If r is not null, sets the default memory resource pointer to r; otherwise, sets the default memory resource pointer to std::pmr::new_delete_resource(). The default memory resource pointer is used by certain facilities when an explicit memory resource is not supplied. The…

std::pmr::pool_options – std::pmr::pool_options Synopsis Defined in header <memory_resource> struct pool_options; (since C++17) std::pmr::pool_options is a set of constructor options for pool resources including std::pmr::synchronized_pool_resource and std::pmr::unsynchronized_pool_resource. Data members Member Meaning std::size_t max_blocks_per_chunk; The maximum number of blocks that will be allocated at once from the upstream std::pmr::memory_resource to replenish the pool. If the value of…

std::pmr::polymorphic_allocator<T>::select_on_container_copy_construction – std::pmr::polymorphic_allocator<T>::select_on_container_copy_construction Synopsis polymorphic_allocator select_on_container_copy_construction() const; (since C++17) Returns a default-constructed polymorphic_allocator object. Parameters (none) Return value A default-constructed polymorphic_allocator object. Notes polymorphic_allocators do not propagate on container copy construction. See also select_on_container_copy_construction obtains the allocator to use after copying a standard container                                       (public static member function of std::allocator_traits<Alloc>) [static]

std::pmr::polymorphic_allocator<T>::resource – std::pmr::polymorphic_allocator<T>::resource Synopsis memory_resource* resource() const; (since C++17) Returns the memory resource pointer used by this polymorphic allocator. Parameters (none) Return value The memory resource pointer used by this polymorphic allocator.

std::pmr::polymorphic_allocator<T>::polymorphic_allocator – std::pmr::polymorphic_allocator<T>::polymorphic_allocator Synopsis polymorphic_allocator() noexcept; (1) polymorphic_allocator(const polymorphic_allocator &other) = default; (2) template <class U> (3) polymorphic_allocator(const polymorphic_allocator<U> &other) noexcept; polymorphic_allocator(memory_resource *r); (4) Constructs a new polymorphic_allocator. 1) Constructs a polymorphic_allocator using the return value of std::pmr::get_default_resource() as the underlying memory resource. 2-3) Constructs a polymorphic_allocator using other.resource() as the underlying memory resource. 4)…

std::pmr::polymorphic_allocator<T>::new_object – std::pmr::polymorphic_allocator<T>::new_object Synopsis template< class U, class CtorArgs… > (since C++20) U* new_object( CtorArgs&&… ctor_args ); Allocates and constructs an object of type U. Equivalent to U *p = allocate_object<U>(); try { construct(p, std::forward<CtorArgs>(ctor_args)…); } catch (…) { deallocate_object(p); throw; } return p; Parameters ctor_args – the arguments to forward to the the constructor…

std::pmr::polymorphic_allocator<T>::destroy – std::pmr::polymorphic_allocator<T>::destroy Synopsis template <class U> (since C++ 17) void destroy(U *p); Destroys the object pointed to by p, as if by calling p->~U(). Parameters p – pointer to the object being destroyed See also destroy destructs an object stored in the allocated storage          (function template) [static]

std::pmr::polymorphic_allocator<T>::deallocate_object – std::pmr::polymorphic_allocator<T>::deallocate_object Synopsis template <class U> (since C++ 20) void deallocate_object(U *p, std::size_t n = 1); Deallocates the storage pointed to by p, which must have been allocated from a std::pmr::memory_resource x that compares equal to *resource().using x.allocate(n * sizeof(U), alignof(U)), typically through a call to allocate_object<U>(n). Equivalent to deallocate_bytes(p, n * sizeof(U), alignof(U));…

std::pmr::polymorphic_allocator<T>::deallocate_bytes – std::pmr::polymorphic_allocator<T>::deallocate_bytes Synopsis void deallocate_bytes(void *p, std::size_t nbytes, (since C++ 20) std::size_t alignment = alignof(std::max_align_t)); Deallocates the storage pointed to by p, which must have been allocated from a std::pmr::memory_resource x that compares equal to *resource(). using x.allocate(nbytes, alignment), typically through a call to allocate_bytes(nbytes, alignment. Equivalent to resorce()->deallocate(p, nbytes, alignment); Parameters p –…

std::pmr::polymorphic_allocator<T>::deallocate – std::pmr::polymorphic_allocator<T>::deallocate Synopsis void deallocate(T *p, std::size_t n); (since C++ 17) Deallocates the storage pointed to by p, which must have been allocated from a std::pmr::memory_resource x that compares equal to *resource() using x.allocate(n * sizeof(T), alignof(T)). Equivalent to this->resource() ->deallocate(p, n * sizeof(T), alignof(T)); Parameters p – pointer to memory to deallocate n…

std::pmr::polymorphic_allocator<T>::construct – std::pmr::polymorphic_allocator<T>::construct Synopsis template < class U, class… Args > (1) (since C++17) void construct( U* p, Args&&… args ); template< class T1, class T2, class… Args1, class… Args2 > void construct( std::pair<T1, T2>* p, (since C++17) std::piecewise_construct_t, (2) (until C++20) std::tuple<Args1…> x, std::tuple<Args2…> y ); template< class T1, class T2 > (3) (since…

std::pmr::polymorphic_allocator<T>::allocate_object – std::pmr::polymorphic_allocator<T>::allocate_object Synopsis template <class U> (since C++ 20) U *allocate_object(std::size_t n = 1); Allocates storage for n objects of type U using the underlying memory resource. If SIZE_MAX / sizeof(U) < n, throws std::length_error, otherwise equivalent to return static_cast<U*>(allocate_bytes(n * sizeof(U), alignof(U)) ); Parameters n – the number of objects to allocate storage…

std::pmr::polymorphic_allocator<T>::allocate_bytes – std::pmr::polymorphic_allocator<T>::allocate_bytes Synopsis void *allocate_bytes(std::size_t nbytes, (since C++ 20) std::size_t alignment = alignof(std::max_align_t)); Allocates nbytes bytes of storage at specified alignment alignment using the underlying memory resource.Equivalent to return resource()->allocate(nbytes, alignment); Parameters nbytes – the number of bytes to allocate alignment – the alignment to use Return value A pointer to the allocated storage….

std::pmr::polymorphic_allocator<T>::allocate – std::pmr::polymorphic_allocator<T>::allocate Synopsis T* allocate( std::size_t n ); (since C++17)                                              (until C++20) [[nodiscard]] T* allocate( std::size_t n ); (since C++20) Allocates storage for n objects of type T using the underlying memory resource. Equivalent to return static_cast<T*>(resource()->allocate(n * sizeof(T), alignof(T))); . Parameters n – the number of objects to allocate storage for Return value…

std::pmr::polymorphic_allocator – std::pmr::polymorphic_allocator Synopsis template< class T > (since C++17) class polymorphic_allocator; (until C++20) template< class T = std::byte > (since C++20) class polymorphic_allocator; The class template std::pmr::polymorphic_allocator is an Allocator whose allocation behavior depends on the memory resource it is constructed with. Thus, different instances of polymorphic_allocator can exhibit entirely different allocation behavior. This…

std::pmr::operator==,std::pmr::operator!= – std::pmr::operator==,std::pmr::operator!= Synopsis bool operator==(const std::pmr::memory_resource &a, (1)(since C++ 17) const std::pmr::memory_resource &b) noexcept; bool operator!=(const std::pmr::memory_resource &a, (2)(since C++ 17) const std::pmr::memory_resource &b) noexcept; Compares the memory_resources a and b for equality. Two memory_resources compare equal if and only if memory allocated from one memory_resource can be deallocated from the other and vice…

std::pmr::null_memory_resource – std::pmr::null_memory_resource Synopsis Defined in header <memory_resource> std::pmr::memory_resource* null_memory_resource() noexcept; (since C++17) Returns a pointer to a memory_resource that doesn’t perform any allocation. Return value Returns a pointer p to a static storage duration object of a type derived from std::pmr::memory_resource, with the following properties: * its allocate() function always throws std::bad_alloc; * its…

std::pmr::new_delete_resource – std::pmr::new_delete_resource Synopsis Defined in header <memory_resource> std::pmr::memory_resource* new_delete_resource() noexcept; (since C++17) Returns a pointer to a memory_resource that uses the global operator_new and operator_delete to allocate memory. Return value Returns a pointer p to a static storage duration object of a type derived from std::pmr::memory_resource, with the following properties: * its allocate() function…

std::pmr::monotonic_buffer_resource::upstream_resource – std::pmr::monotonic_buffer_resource::upstream_resource Synopsis std::pmr::memory_resource* upstream_resource() const; (since C++17) Returns a pointer to the upstream memory resource. This is the same value as the upstream argument passed to the constructor of this object. See also               Constructs a monotonic_buffer_resource constructor (public member function)