/* * Copyright (c) 2019 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ #ifndef __OS_PROC__ #define __OS_PROC__ #include <stddef.h> #include <sys/cdefs.h> #include <os/availability.h> /*! * @header * * @preprocinfo * This is for functions that operate on the calling process alone. */ __BEGIN_DECLS /*! * @function os_proc_available_memory * * @abstract * Return the number of bytes remaining, at the time of the call, before the * current process will hit its current dirty memory limit. * * @discussion * Developers can query this value efficiently whenever it is needed. The return * value is only a snapshot at the time of the call. Caching the result is not * advised. The result may be instantaneously invalidated by actions taken in * another thread or another framework. * * Memory limits can change during the app life cycle. Make sure to check accordingly. * * The size returned is not representative of the total memory of the device, it * is the current dirty memory limit minus the dirty memory footprint used at the * time of the query. * * This interface allows an app to efficiently consume all available memory resources. * Significant memory use, even under the current memory limit, may still cause * system-wide performance including the termination of other apps and system * processes. Take care to use the minimum amount of memory needed to satisfy the * user’s need. * * If you need more information than just the available memory, you can use task_info(). * The information returned is equivalent to the task_vm_info.limit_bytes_remaining * field. task_info() is a more expensive call, and will return information such * as your phys_footprint, which is used to calculate the return of this function. * * Dirty memory contains data that must be kept in RAM (or the equivalent) even * when unused. It is memory that has been modified. * * @param none * * @result * The remaining bytes. 0 is returned if the calling process is not an app, or * the calling process exceeds its memory limit. */ API_UNAVAILABLE(macos) API_AVAILABLE(ios(13.0), tvos(13.0), watchos(6.0), bridgeos(4.0)) extern size_t os_proc_available_memory(void); __END_DECLS #endif