The Apache Portable Runtime (APR) is a supporting library for the

Apache The Apache () are a group of culturally related Native American tribes in the Southwestern United States, which include the Chiricahua, Jicarilla, Lipan, Mescalero, Mimbreño, Ndendahe (Bedonkohe or Mogollon and Nednhi or Carrizaleño an ...

web server A web server is computer software and underlying hardware that accepts requests via HTTP (the network protocol created to distribute web content) or its secure variant HTTPS. A user agent, commonly a web browser or web crawler, initiate ...

. It provides a set of

API An application programming interface (API) is a way for two or more computer programs to communicate with each other. It is a type of software Interface (computing), interface, offering a service to other pieces of software. A document or standa ...

s that map to the underlying operating system (OS). Where the OS does not support a particular function, APR will provide an emulation. Thus programmers can use the APR to make a program truly portable across platforms. APR originally formed a part of

Apache HTTP Server The Apache HTTP Server ( ) is a free and open-source cross-platform web server software, released under the terms of Apache License 2.0. Apache is developed and maintained by an open community of developers under the auspices of the Apache So ...

, but the

Apache Software Foundation The Apache Software Foundation (ASF) is an American nonprofit corporation (classified as a 501(c)(3) organization in the United States) to support a number of open source software projects. The ASF was formed from a group of developers of the A ...

spun it off into a separate project. Other applications can use it to achieve platform independence.

Functionality

The range of platform-independent functionality provided by APR includes: *

Memory allocation Memory management is a form of Resource management (computing), resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their re ...

and

memory pool Memory pools, also called fixed-size blocks allocation, is the use of pools for memory management that allows dynamic memory allocation comparable to malloc or C++'s operator new. As those implementations suffer from fragmentation because of va ...

functionality *

Atomic operations In concurrent programming, an operation (or set of operations) is linearizable if it consists of an ordered list of invocation and response events (event), that may be extended by adding response events such that: # The extended list can be re-e ...

* Dynamic

library A library is a collection of materials, books or media that are accessible for use and not just for display purposes. A library provides physical (hard copies) or digital access (soft copies) materials, and may be a physical location or a vir ...

handling * File I/O * Command-argument parsing * Locking *

Hash table In computing, a hash table, also known as hash map, is a data structure that implements an associative array or dictionary. It is an abstract data type that maps keys to values. A hash table uses a hash function to compute an ''index'', als ...

s and

array An array is a systematic arrangement of similar objects, usually in rows and columns. Things called an array include: {{TOC right Music * In twelve-tone and serial composition, the presentation of simultaneous twelve-tone sets such that the ...

s *

Mmap In computing, mmap(2) is a POSIX-compliant Unix system call that maps files or devices into memory. It is a method of memory-mapped file I/O. It implements demand paging because file contents are not immediately read from disk and initially use no ...

functionality * Network sockets and protocols * Thread,

process A process is a series or set of activities that interact to produce a result; it may occur once-only or be recurrent or periodic. Things called a process include: Business and management *Business process, activities that produce a specific se ...

and

mutex In computer science, a lock or mutex (from mutual exclusion) is a synchronization primitive: a mechanism that enforces limits on access to a resource when there are many threads of execution. A lock is designed to enforce a mutual exclusion concu ...

functionality *

Shared memory In computer science, shared memory is memory that may be simultaneously accessed by multiple programs with an intent to provide communication among them or avoid redundant copies. Shared memory is an efficient means of passing data between progr ...

functionality *

Skip list In computer science, a skip list (or skiplist) is a probabilistic data structure that allows \mathcal(\log n) average complexity for search as well as \mathcal(\log n) average complexity for insertion within an ordered sequence of n elements. ...

functionality * Time routines * User and group ID services

Similar projects

GLib GLib is a bundle of three (formerly five) low-level system libraries written in C and developed mainly by GNOME. GLib's code was separated from GTK, so it can be used by software other than GNOME and has been developed in parallel ever sinc ...

– provides similar functionality. It supports many more data structures and OS-independent functions, but fewer IPC-related functions. (GLib lacks local and global locking and shared-memory management.) *

Netscape Portable Runtime In computing, the Netscape Portable Runtime, or NSPR, a platform abstraction library, makes all operating systems it supports appear the same to (for example) Mozilla-style web-browsers. NSPR provides platform independence for non-GUI operatin ...

(NSPR) is a cross-platform abstraction library used by the

Mozilla Mozilla (stylized as moz://a) is a free software community founded in 1998 by members of Netscape. The Mozilla community uses, develops, spreads and supports Mozilla products, thereby promoting exclusively free software and open standards, wi ...

project. It is used by another subproject of

Mozilla application framework The Mozilla application framework is a collection of cross-platform software components that make up the Mozilla applications. It was originally known as XPFE, an abbreviation of cross-platform front end. It was also known as XPToolkit. To avoid c ...

(XPFE) to provide cross-platform

graphical user interface The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, inste ...

(GUI) functionality. *

Adaptive Communication Environment The Adaptive Communication Environment (ACE) is an open source software framework used for network programming. It provides a set of object-oriented C++ classes designed to help address the inherent complexities and challenges in network program ...

(ACE) is an object-oriented library written in C++ similar in functionality to APR. It is widely deployed in commercial products.
commonc++
is a cross-platform C++ class library for systems programming, with much of the same functionality as APR. *

POCO Poco was an American country rock band originally formed in 1968 after the demise of Buffalo Springfield. Guitarists Richie Furay and Jim Messina, former members of Buffalo Springfield, were joined by multi-instrumentalist Rusty Young, bassi ...

is a modern C++ framework similar in concept but more extensive than APR. *

WxWidgets wxWidgets (formerly wxWindows) is a widget toolkit and tools library for creating graphical user interfaces (GUIs) for cross-platform applications. wxWidgets enables a program's GUI code to compile and run on several computer platforms with mini ...

is an object-oriented cross-platform GUI library that also provides abstraction classes for database communication, IPC and networking functionality. *

KDE Frameworks KDE Frameworks is a collection of libraries and software frameworks readily available to any Qt-based software stacks or applications on multiple operating systems. Featuring frequently needed functionality solutions like hardware integration, fi ...

– used by

KDE SC KDE is an international Free software movement, free software community that develops free and open-source software. As a central development hub, it provides tools and resources that allow collaborative work on this kind of software. Well-know ...

References

External links

* {{Apache Software Foundation Portable Runtime C (programming language) libraries Free computer libraries Free software programmed in C Application programming interfaces Software using the Apache license