Apache Portable Runtime

Developer(s)	Apache Software Foundation
Stable release	1.4.5
Development status	Active
Written in	C
Operating system	Cross-platform
Type	Development Library
License	Apache License 2.0
Website	http://apr.apache.org

The Apache Portable Runtime (APR) is a supporting library for the Apache web server. It provides a set of APIs that map to the underlying operating system (OS). Where the OS doesn't 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, but the Apache Software Foundation 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 and memory pool functionality
• Atomic operations
• Dynamic library handling
• File I/O
• Command-argument parsing
• Locking
• Hash tables and arrays
• Mmap functionality
• Network sockets and protocols
• Thread, process and mutex functionality
• Shared memory functionality
• Time routines
• User and group ID services

Similar projects

• Glib 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.)
• NSPR is a cross-platform abstraction library used by the Mozilla project. It is used by another subproject of Mozilla XPFE to provide cross-platform graphical user interface (GUI) functionality.
• Adaptive Communication Environment (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 is a modern C++ framework similar in concept but more extensive than APR.
• WxWidgets is an object-oriented cross-platform GUI library that also provides abstraction classes for database communication, IPC and networking functionality.
• Qt, a cross-platform application development framework with similar features, can also foster GUI development.

External links

• Official website
• The current APR programming documentation
• The Apache Software Foundation website
• APR programming tutorial
• APR wikibooks tutorial (inactive)