@node Does GNUstep run on Windows?, What is GNUstep's position towards KDE and the GNOME project?, What platforms does GNUstep run on?, GNUstep General Information
@subsection Does GNUstep run on Windows?
The primary targets for GNUstep are free 'Unix' platforms such
The gui library needs a win32 backend library to work under
Windows-NT. The backend library is a thin layer that converts the
GNUstep methods to handle drawing of GUI elements to calls to the
win32 api. This is a project looking for a volunteer.
The application-wrapper used for GNUstep already allows for multiple
binaries to be stored for different systems, so you should be able
to write once, deploy anywhere.
@node What is GNUstep's position towards KDE and the GNOME project?, Is the Objective C API for GTK related?, Does GNUstep run on Windows?, GNUstep General Information
@subsection What is GNUstep's position towards KDE and the GNOME project?
You can use GNUstep with GNOME and/or KDE. GNUstep displays
on top of X11. You can still do programming in C (since Objective-C
is just a superset of C), and when (if?) GCC gets around to it,
you'll be able to mix C++ and Objective-C code in the SAME file.
GNUstep, is much more than a window manager or desktop environment.
It frees you to develop cross-platform applications without the
work of developing an OS independent framework from scratch. It
gives you lots of basic functionality, from Font Panels to Unicode
strings to Distributed Objects.
@node Is the Objective C API for GTK related?, How about implementing parts of the Application Kit with GTK?, What is GNUstep's position towards KDE and the GNOME project?, GNUstep General Information
@subsection Is the Objective C API for GTK related?
No. GNUstep applications provide their GUI via the OpenStep
API, which provides fully object-oriented access to GUI manipulation.
The object-oriented nature of the libraries and language make it much easier
for new users to create their own subclasses rather than simply using the
supplied widgets as in other frameworks.
@node How about implementing parts of the Application Kit with GTK?, Which compiler can I use? Where can I get it?, Is the Objective C API for GTK related?, GNUstep General Information
@subsection How about implementing parts of the Application Kit with GTK?
Yes and No - The GNUstep architecture provides a single,
platform-independent, API for handling all aspects of GUI interaction
(implemented in the gstep-gui library), with a backend architecture
that permits you to have different display models (display postscript,
X-windows, win32, berlin ...) while letting you use the same code
for printing as for displaying. Use of GTK in the frontend gui
library would remove some of those advantages without adding any.
That being said, a backend library could be implemented using gtk
if anyone wanted to do so. Since the frontend library handles most
of the work involved in implementing the OpenStep API, the backend
is a relatively thin layer and the advantages of GTK over direct
xlib or win32 calls is likely to be minimal. If/when GTK is ported
to more systems, a backend written using it could be a valuable
asset - volunteers are, as always, wecome.
@node Which compiler can I use? Where can I get it?, Which Foundation Library can I use?, How about implementing parts of the Application Kit with GTK?, GNUstep General Information
@subsection Which compiler can I use? Where can I get it?
Use gcc-2.8.1 or later, from any GNU ftp site or, on some
platforms you must use egcs-1.1.1 or later, from http://egcs.cygnus.com/
@node Which Foundation Library can I use?, How do you use the gnustep-make package?, Which compiler can I use? Where can I get it?, GNUstep General Information
@subsection Which Foundation Library can I use?
That depends ...
If you only want to use the database package - gnustep-db, you can
use either the gnustep base library or libFoundation.
If you want to develop/use GNUstep gui applications, you must use
the gnustep-base library since libFoundation is (13-Feb-2000)
missing much essential functionality.
@node How do you use the gnustep-make package?, How can I get GNUstep?, Which Foundation Library can I use?, GNUstep General Information
@subsection How do you use the gnustep-make package?
Good question. Read the tutorials at the GNUstep web site. Also, use the
makefiles in the libraries, tool directories, and test applications as
examples.
@node How can I get GNUstep?, How do you run GNUstep?, How do you use the gnustep-make package?, GNUstep General Information
@node Can I run NeXT OPENSTEP or Apple Rhapsody programs on GNUstep?, Is it easy to port OPENSTEP and Rhapsody programs to GNUstep?, Compatibility with OPENSTEP/Cocoa/MacOSX, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Is it easy to port OPENSTEP and Rhapsody programs to GNUstep?, Can I transfer archived data from GNUstep to Cocoa?, Can I run NeXT OPENSTEP or Apple Rhapsody programs on GNUstep?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Can I transfer archived data from GNUstep to Cocoa?, Does distributed objects work between GNUstep and Cocoa?, Is it easy to port OPENSTEP and Rhapsody programs to GNUstep?, Compatibility with OPENSTEP/Cocoa/MacOSX
@subsection Can I transfer archived data from GNUstep to Cocoa?
Apple's archiving format is proprietary and not documented, so this
poses a problem for anyone wanting to implement compatibility with it.
However, even if we reverse engineered the format, there are enough
differences between the class and ivar layouts to make this sort of
compatibility difficult. Not to mention the fact that we would
constantly have to keep up with the changes Apple made. Also Apple's
archiving format, as far as we know, would not be compatible between
different machines because of endiness issues, although GNUstep doesn't
have this problem.
Your best bet is to implement your own archiving format that would work
both with GNUstep and Cocoa. Fortuneatly, you don't have to start from
scratch, since this has been essentially done for you in the nib2gmodel
tool, which has an archiver that works both on GNUstep and Cocoa. It
might be nice to split this off into a separate project to make it
easier for other people to do the same thing.
@node Does distributed objects work between GNUstep and Cocoa?, Is there an Interface Builder for GNUstep?, Can I transfer archived data from GNUstep to Cocoa?, Compatibility with OPENSTEP/Cocoa/MacOSX
@subsection Does distributed objects work between GNUstep and Cocoa?
See the answer to the previous question (on archive compatibility) for
why this won't work either.
@node Is there an Interface Builder for GNUstep?, Can I use my original NIB files?, Does distributed objects work between GNUstep and Cocoa?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Can I use my original NIB files?, Will code without NIB files work?, Is there an Interface Builder for GNUstep?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Will code without NIB files work?, Is GNUstep following Apple's Changes to OpenStep?, Can I use my original NIB files?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Is GNUstep following Apple's Changes to OpenStep?, Do we have to have the NeXTstep look and feel?, Will code without NIB files work?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Do we have to have the NeXTstep look and feel?, Can one use the hybrid "Objective-C++", Is GNUstep following Apple's Changes to OpenStep?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Can one use the hybrid "Objective-C++", Is there a plan to support Java/YellowBox Bindings?, Do we have to have the NeXTstep look and feel?, Compatibility with OPENSTEP/Cocoa/MacOSX
@node Is there a plan to support Java/YellowBox Bindings?, What if I compile GNUstep under OPENSTEP/MacOS X Server?, Can one use the hybrid "Objective-C++", Compatibility with OPENSTEP/Cocoa/MacOSX
@node What if I compile GNUstep under OPENSTEP/MacOS X Server?, , Is there a plan to support Java/YellowBox Bindings?, Compatibility with OPENSTEP/Cocoa/MacOSX
In order to use this you will also need a recent (v 1.3.2 or later) copy of
Guile (you can get this from a GNU ftp site) and will need to hacke checked
out, built, and installed the 'guile' package from the GNUstep CVS repository.
@node How do I start writing applications?, How can I help with the GNUstep website?, How do I start writing tests?, Compiling and Developing
@subsection How do I start writing applications?
You can either look at the links on the GNUstep website for
applications that have been started, and email their owners to
volunteer to help, or you can start your own project.
@node How can I help with the GNUstep website?, How do I compile GNUstep on my machine? , How do I start writing applications?, Compiling and Developing
@subsection How can I help with the GNUstep website?
Talk to Adam Fedor @email{fedor@@gnu.org}, the maintainer.
The GNUstep website is kept as a CVS module, but the largest portions
of it (the FAQ, the TODO list, and the Documentation) are actually
generated from files in the individual GNUstep packages.
If you want to update the FAQ or TODO list or documentation - grab
the latest snapshot of the GNUstep core you can find, update it
from the CVS repository, and work with the contents of the appropriate
The main task with the website is to figure out which bits are
out-of-date (or wrong) and update/mark-as-outdated as required.
@node How do I compile GNUstep on my machine? , Are there any precompiled packages available?, How can I help with the GNUstep website?, Compiling and Developing
@subsection How do I compile GNUstep on my machine?
Read the file @file{GNUstep-HOWTO}, which comes with the GNUstep
@node Are there any precompiled packages available?, What are these type and size warnings?, How do I compile GNUstep on my machine? , Compiling and Developing
@node GNU Objective C Compiler and Objective C Runtime Library, GNUstep Base Library, Compiling and Developing, Top
@section GNU Objective C Compiler and Objective C Runtime Library
@menu
* What is the Objective C Runtime Library?::
* Does it allow a mixture of Objective C and C++::
* Where can I find more information?::
@end menu
@node What is the Objective C Runtime Library?, Does it allow a mixture of Objective C and C++, GNU Objective C Compiler and Objective C Runtime Library, GNU Objective C Compiler and Objective C Runtime Library
@subsection What is the Objective C Runtime Library?
The Objective C Runtime Library provides C functions and data structures
required to execute an Objective C program.
The GNU Objective C Runtime Library offers everything NeXT's runtime
does, including Categories, Protocols, @samp{+poseAs:}, thread-safety,
class initialization on demand, delayed loading of classes, and
initialization of static instances (such as @@""-style string objects).
It also has several improvements over NeXT's implementation:
@itemize @bullet
@item NeXT's runtime requires an extra function call (objc_msgSend) for
each message that is sent; (the function looks up the receiving
instance's implementation of the method). GNU's implementation is
faster because it does not use an extra function call. Instead, it
inlines a short piece of code that makes two pointer hops into a method
dispatch table; because the code is inlined, it does not incur the
overhead of a function call.
@item When running in thread-safe mode, NeXT's runtime must aquire a
global mutual exclusion lock every time a message is sent; this is
extremely slow. GNU's runtime, amazingly, sends messages just as fast
in thread-safe mode as it does in single-thread mode---the code path
does not contain even a single extra instruction! The GNU runtime only
needs locks when certainly structures are written, not read; the
structures are written relatively infrequently: only at class
initialization and when @samp{+poseAs:} is called.
@item GNU's runtime provides ``selector-types'' along with each
selector; NeXT's does not. A selector-type is a string that describes
the C variable types for the method's return and argument values. Among
other uses, selector-types is extrememly helpful for fast distributed
objects implementations, (see GNUstep Base Library Section, below).
@item Many of the GNU functions have different names than their
corresponding NeXT functions; the GNU names conform to the GNU coding
standards.
@item NeXT's compiler, @samp{cc}, is based on an old version of
@samp{gcc}. GNU's compiler is, of course, the latest version of
@samp{gcc}, and therefore contains all the latest enhancements.
@end itemize
@node Does it allow a mixture of Objective C and C++, Where can I find more information?, What is the Objective C Runtime Library?, GNU Objective C Compiler and Objective C Runtime Library
@subsection Does it allow a mixture of Objective C and C++?
No. Unlike NeXT's @samp{cc}, GNU GCC does not support source files
notifications, notification dispatchers, moments in time, network ports,
remote object messaging support (distributed objects), event loops, and
random number generators.
It provides functionality that aims to implement the non-graphical
portion of the OpenStep standard (the Foundation library).
@node What is base's current state of development?, What are the features of GNU Distributed Objects?, What is the GNUstep Base Library?, GNUstep Base Library
@subsection What is its current state of development?
@node What are the features of GNU Distributed Objects?, , What is base's current state of development?, GNUstep Base Library
@subsection What are the features of GNU Distributed Objects?
GNU Distributed Objects has many of the features of other distributed
objects implementations, but, since it is free software, it can be
ported to platforms for which other distributed objects implementations
are not available.
[NOTE: The GNU distributed object facilities have the same ease-of-use
as NeXT's; be warned, however, that they are not compatible with each
other. They have different class heirarchies, different instance
variables, different method names, different implementation strategies
and different network message formats. You cannot communicate with a
NeXT NSConnection using a GNU Connection.
Here are some differences between GNU distributed objects and NeXT's
distributed objects: NeXT NSDistantObject asks it's remote
target for the method encoding types and caches the results; GNU
NSDistantObject gets the types directly from the local GNU "typed selector"
mechanism if the information is known locally and only queries the remote
target or caching encoding types when using a method that is not known to
the local process. The NSProxy for the remote root object always has name 0
and, once set, you cannot change the root object of a NSConnection; the GNU
Proxy for the remote root object has a target address value just like
all other Proxy's, and you can change the root object as many times as
you like. ].
@c --------------------------GNUstep Base Library----------------------
@node GNUstep GUI Library, GNUstep DisplayGhostScript Server, GNUstep Base Library, Top
@section GNUstep GUI Library
@menu
* What is the GUI Library?::
* Explain the organization of the front- and back-ends::
* What is the current state of development of the front-end?::
* What is the current state of development of the X/DPS back-end?::
@end menu
@node What is the GUI Library?, Explain the organization of the front- and back-ends, GNUstep GUI Library, GNUstep GUI Library
@subsection What is the GUI Library?
The GNUstep GUI Library is a library of objects useful for writing
graphical applications. For example, it includes classes for drawing
and manipulating graphics objects on the screen: windows, menus,
buttons, sliders, text fields, and events. There are also many
peripheral classes that offer operating-system-independent interfaces to
images, cursors, colors, fonts, pasteboards, printing. There are also
workspace support classes such as data links, open/save panels,
context-dependent help, spell checking.
It provides functionality that aims to implement the @samp{AppKit}
portion of the OpenStep standard. However the implementation has
been written to take advantage of GNUstep enhancements wherever possible.
@node Explain the organization of the front- and back-ends, What is the current state of development of the front-end?, What is the GUI Library?, GNUstep GUI Library
@subsection Explain the organization of the front- and back-ends
The GNUstep GUI Library is divided into a front- and back-end. The
front-end contains the majority of implementation, but leaves out the
low-level drawing and event code. A back-end can override whatever
methods necessary in order to implement low-level drawing event
receiving. Different back-ends will make GNUstep available on various
platforms. The default GNU back-end will run on top of X Windows and
the DisplayGhostScript Server. Other back-ends could allow GNUstep to
run on OpenGL, OS/2, and WIN32 graphics/event platforms. Much work
will be saved by this clean separation between front- and back-end,
because it allows different platforms to share the large amount of
front-end code.
@node What is the current state of development of the front-end?, What is the current state of development of the X/DPS back-end?, Explain the organization of the front- and back-ends, GNUstep GUI Library
@subsection What is the current state of development of the front-end?
Many of the classes are well implemented, if not thouroughly tested.
See the GNUstep web sites and read status information contained in the
distribution for the most up-to-date information.
@node What is the current state of development of the X/DPS back-end?, , What is the current state of development of the front-end?, GNUstep GUI Library
@subsection What is the current state of development of the X/DPS back-end?
It works, but is slow and buggy. A lot of work could be done.
@node GNUstep DisplayGhostScript Server, , GNUstep GUI Library, Top
@section GNUstep DisplayGhostScript Server
@menu
* What is the Display Ghostscript Server?::
* What is DGSs current state of development?::
* What is the relationship between the Display Ghostscript Server and X Windows?::
@end menu
@node What is the Display Ghostscript Server?, What is DGSs current state of development?, GNUstep DisplayGhostScript Server, GNUstep DisplayGhostScript Server
@subsection What is the Display Ghostscript Server?
It is a free implementation of a Display PostScript server based on the
@node What is DGSs current state of development?, What is the relationship between the Display Ghostscript Server and X Windows?, What is the Display Ghostscript Server?, GNUstep DisplayGhostScript Server
@subsection What is its current state of development?
@node What is the relationship between the Display Ghostscript Server and X Windows?, , What is DGSs current state of development?, GNUstep DisplayGhostScript Server
@subsection What is the relationship between the Display Ghostscript Server and X Windows?
Display Ghostscript runs on top of X Windows.
@c ------------------ GNUstep DisplayGhostScript Server ---------------
@format
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