View source for GNUstep

{{Short description|Open source widget toolkit and application development tools}}
{{Multiple issues|
{{more citations needed|date=January 2010}}
{{prose|date=January 2012}}
{{primary sources|date=February 2011}}
}}

{{Infobox software
| name = GNUstep
| logo = GNUstep logo.svg
| logo size = 100px
| screenshot = Gnustep.png
| screenshot size = 300px
| caption = Window Maker and a variety of applications were developed with the GNUstep libraries, including a [[gomoku]] game, [[calculator]], and [[TextEdit]].
| developer = GNUstep Developers
| latest_release_version = make 2.9.3, base 1.31.1, gui 0.32.0, back 0.32.0
| latest_release_date = {{start date and age|2025|02|28}}
| latest preview version = on the GitHub software repository
| operating_system = [[Cross-platform]]
| programming language = [[Objective-C]]
| genre = [[Widget toolkit]]
| license = [[GNU General Public License]] for the applications <br /> [[GNU Lesser General Public License]] for the libraries.
| website = {{URL|https://www.gnustep.org/}}
}}

'''GNUstep''' is a [[free software]] implementation of the [[Cocoa (API)|Cocoa]] (formerly [[OpenStep]]) [[Objective-C]] [[Software framework|frameworks]], [[widget toolkit]], and application development tools for [[Unix-like]] [[operating system]]s and [[Microsoft Windows]]. It is part of the [[GNU Project]].

GNUstep features a cross-platform, object-oriented [[Integrated development environment|IDE]].  Apart from the default [[Objective-C]] interface, GNUstep also has [[language binding|bindings]] for [[Java (programming language)|Java]], [[Ruby (programming language)|Ruby]],<ref>{{cite web|url=http://www.gnustep.org/experience/RIGS.html|title=GNUstep Developer Tools - RIGS|website=www.gnustep.org|access-date=10 April 2018}}</ref> [[GNU Guile]] and [[Scheme (programming language)|Scheme]].<ref>[https://web.archive.org/web/20051218234159/http://www.gnustep.it/marko/GScheme GScheme<!-- Bot generated title -->] {{webarchive|url=https://web.archive.org/web/20051218234159/http://www.gnustep.it/marko/GScheme/ |date=2005-12-18 }}</ref> The GNUstep developers track some additions to Apple's [[Cocoa (API)|Cocoa]] to remain compatible. The roots of the GNUstep application interface are the same as the roots of Cocoa: [[NeXTSTEP]] and [[OpenStep]]. GNUstep thus predates Cocoa, which emerged when [[Apple Inc.|Apple]] acquired [[NeXT]]'s technology and incorporated it into the development of the original [[macOS|Mac OS X]], while GNUstep was initially an effort by [[GNU Project|GNU]] developers to replicate the technically ambitious NeXTSTEP's programmer-friendly features.

== History ==
GNUstep began when [[Paul Kunz]] and others at [[Stanford Linear Accelerator Center]] wanted to port [[HippoDraw]] from [[NeXTSTEP]] to another platform. Instead of rewriting HippoDraw from scratch and reusing only the application design, they [[Rewrite (programming)|decided to rewrite]] the NeXTSTEP [[object-oriented programming|object]] layer on which the application depended. This was the first version of ''libobjcX''. It enabled them to port HippoDraw to Unix systems running the [[X Window System]] without changing a single line of their application source. After the OpenStep specification was released to the public in 1994, they decided to write a new ''objcX'' which would adhere to the new APIs. The software would become known as "GNUstep".<ref>{{cite web|url=http://gnustep.made-it.com/Guides/History.html|title=GNUstep History|website=gnustep.made-it.com|access-date=10 April 2018}}</ref>

== Software architecture==
[[File:Free and open-source-software display servers and UI toolkits.svg|thumb|Software components of the Linux desktop include the [[display server]], [[widget toolkit|graphics control element libraries]], and [[graphical shell]]s.]]

The [[Foundation Kit]] provides basic classes such as wrapper classes and data structure classes. The [[Application Kit]] provides classes oriented around [[graphical user interface]] capabilities. GNUstep contains a set of [[graphical control element]]s written in the Objective-C programming language.

The [[graphical user interface]] (GUI) of [[GNUMail]] is composed of graphics control elements. GNUMail has to interact with the [[windowing system]], e.g. [[X Window System core protocol|X11]] or [[Wayland (protocol)|Wayland]], and its graphical user interface has to be [[Rendering (computer graphics)|rendered]]. GNUstep's backend provides a small set of functions used by the user interface library to interface to the actual [[windowing system]]. It also has a [[rendering engine]] which emulates common [[PostScript|Postscript]] functions. The package gnustep-back provides the following backends:

* cairo – default backend using the [[cairo (graphics)|Cairo]] 2D graphics library.
* winlib – default backend on Microsoft Windows systems. Cairo and [[Windows API]] variants.
* art – old (deprecated) backend on unix-like systems. Uses the vector-based PostScript-like 2D graphics library [[Libart]].
* [[xlib]] – old (deprecated) X11 backend.

GNUstep inherits some design principles proposed in OPENSTEP (GNUstep predates Cocoa, but Cocoa is based on OPENSTEP) as well as the [[Objective-C]] language.

* [[Model–view–controller]] paradigm
* [[Target–action]]
* [[Drag-and-drop]]
* [[Delegation (computer science)|Delegation]]
* [[Message passing|Message forwarding]] (through NSInvocation)

In addition to the Objective-C interface, some small projects under the GNUstep umbrella implement other APIs from Apple:
* The Boron library aims to implement the [[Carbon (API)|Carbon API]]. It is very incomplete.
* The CoreBase library is designed to be compatible with [[Core Foundation]]. It is not complete enough for the Base (Foundation Kit) component to simply be a wrapper around it.
* The QuartzCore library implements [[Core Animation]] APIs. The Opal library implements [[Quartz 2D]].
{{as of|2020|02}}, there are no projects that build the [[Swift programming language]] against the GNUstep Objective-C environment.

== Applications ==
Here are some examples of applications written for or ported to GNUstep.

{{See also|Category:Software that uses GNUstep}}

=== Original ===
* Addresses, an address/[[contacts manager]]
* Étoilé, a [[desktop environment]]
* [[GNUMail]], an [[e-mail client]]
* GNUstep Database Library 2, an [[Enterprise Objects Framework]] clone
* [[GNUstepWeb]], an application server compatible with WebObjects 4.x
* [[Gorm (computing)|Gorm]], a [[user interface]] builder application, and part of the developer tools of GNUstep. Gorm is the equivalent of [[Interface Builder]] that was originally found on [[NeXTSTEP]], then [[OPENSTEP]], and finally on [[Mac OS X]]. It supports the old ''.nib'' files as well as its own ''.gorm'' file format.
* GWorkspace, a workspace and [[file manager]]
* Grr, an [[RSS Feed Reader|RSS feed reader]]
* ''[[Oolite (video game)|Oolite]]'', a clone of ''[[Elite (video game)|Elite]]'', a space simulation game with trading components
* PRICE, imaging application
* ProjectCenter, the [[Project Builder]] or [[Xcode]] equivalent.
* TalkSoup, an [[IRC]] client
* [[Terminal (macOS)|Terminal]]
* Zipper, a [[file archiver]] tool
* [[Window Maker]] is a [[window manager]] that emulates [[NeXTSTEP]]'s [[graphical user interface|GUI]] as an [[OpenStep]]-compatible environment.<ref>{{Cite web|url=https://www.linuxinsider.com/story/window-maker-live-cool-retro-look-even-cooler-performance-84768.html|title=Window Maker Live: Cool Retro Look, Even Cooler Performance|date=August 28, 2017|website=LinuxInsider}}</ref> It was launched in 1997 as an improved take on [[AfterStep]]'s design.<ref>{{Cite web|url=https://www.zdnet.com/article/the-best-old-school-linux-window-managers-that-still-hold-up/|title=The best old-school Linux window managers that still hold up|date=1 October 2024|website=ZDNET}}</ref>

=== Ported from NeXTSTEP, OPENSTEP, or macOS ===
* Adun
* BioCocoa
* [[Chess (Mac OS)|Chess]]
* Cenon
* DoomEd
* EdenMath
* Eggplant
* [[Emacs]]
* Fortunate
* ''[[Gomoku]]''
* NeXTGO
* PikoPixel
* [[TextEdit]]
* TimeMon

=== Forks of GNUstep ===
* [[Universal Windows Platform]], which includes a [[WinObjC]] suite consisting of various parts of GNUstep and [[Microsoft]]'s own implementations of things like the [[Cocoa Touch]] API.<ref name=libobjc>{{cite web |title=GNUstep Objective-C Runtime 2.0 |url=https://github.com/gnustep/libobjc2/releases/tag/v2.0 |website=GitHub |quote=Note: Microsoft's WinObjC project contains a friendly fork of this library that includes a work around for the incremental linking issue.}}</ref>

== See also ==
{{Portal|Free and open-source software}}
* [[Darling (software)]], a compatibility layer that relies on GNUstep
* [[GNUstep fat bundle]]
* [[GNUstep Renaissance]], framework for XML description of portable GNUstep/Mac OS X [[user interface]]s
* [[Miller columns]], the method of file tree browsing the GWorkspace File Viewer uses
* [[Property list]], often-used file format to store user settings
* [[StepTalk]], scripting framework

==References==
{{Reflist}}

==External links==
{{Commons}}
* {{official |url=https://gnustep.org/}}
* [https://gap.nongnu.org/ GNUstep Application Project]
* [http://www.network-theory.co.uk/articles/pero.html A 2003 interview with GNUstep developer Nicola Pero] {{webarchive|url=https://web.archive.org/web/20070107021109/http://www.network-theory.co.uk/articles/pero.html |date=2007-01-07 }}
* [https://twit.tv/floss44 FLOSS Weekly Interview with Gregory Casamento and Riccardo Mottola from GNUstep]

{{GNU}}
{{Widget toolkits}}
{{Software in the Public Interest}}

{{DEFAULTSORT:Gnustep}}
[[Category:GNUstep| ]]
[[Category:Compatibility layers]]
[[Category:Cross-platform free software]]
[[Category:Free software programmed in Objective-C]]
[[Category:GNU Project software]]
[[Category:NeXT]]
[[Category:Software that uses Cairo (graphics)]]
[[Category:Widget toolkits]]
[[Category:X Window System]]