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620 lines
28 KiB
Text
620 lines
28 KiB
Text
\input texinfo @c -*-texinfo-*-
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@c A FAQ for GNUstep
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@node Top, Compatibility, (dir), (dir)
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@chapter GNUstep Frequently Asked Questions with Answers
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Last updated @today{}.
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Please send corrections to @email{gnustep-maintainer@@gnu.org}. Also look
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at the user FAQ for more user oriented questions.
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@menu
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* Compatibility::
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* Compiling and Developing::
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* GNU Objective C Compiler and Runtime::
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* GNUstep Base Library::
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* GNUstep GUI Library::
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* GNUstep DisplayGhostScript Server::
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@end menu
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@c ****************************************************************
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@c Compiling
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@node Compatibility, Compiling and Developing, Top, Top
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@section Compatibility
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@menu
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* Is it easy to port OPENSTEP programs to GNUstep?::
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* How about porting between Cocoa and GNUstep?::
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* Tools for porting::
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* Can I transfer archived data from GNUstep to Cocoa?::
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* Does distributed objects work between GNUstep and Cocoa?::
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* Is there an Interface Builder for GNUstep?::
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* Can I use my original NIB files?::
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* Can one use the hybrid "Objective-C++"::
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* Is there a plan to support Java/YellowBox Bindings?::
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* What if I compile GNUstep under OPENSTEP/MacOS X?::
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* Is the Objective C API for GTK related?::
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* How about implementing parts of the Application Kit with GTK?::
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@end menu
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@node Is it easy to port OPENSTEP programs to GNUstep?, How about porting between Cocoa and GNUstep?, Compatibility, Compatibility
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@subsection Is it easy to port OPENSTEP programs to GNUstep?
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It is probably easy for simple programs. There are some portability
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tools to make this easier, or rewrite
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the Makefiles yourself. You will also have to translate the NIB files
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(if there are any) to GNUstep model files using the nib2gmodel program
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(from @url{ftp://ftp.gnustep.org/pub/gnustep/dev-apps}).
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@node How about porting between Cocoa and GNUstep?, Tools for porting, Is it easy to port OPENSTEP programs to GNUstep?, Compatibility
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@subsection How about porting between Cocoa and GNUstep?
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It's easier from GNUstep to Cocoa than Cocoa to GNUstep. Cocoa is
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constantly changing, much faster than GNUstep could hope to keep
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up. They have added extensions and new classes that aren't available in
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GNUstep yet. Plus there are some other issues. If you start with
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Cocoa:
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@itemize @bullet
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@item Use #ifndef GNUSTEP for Apple only code.
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@item Do not use CoreFoundation
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@item Do not use Objective-C++ (except with gcc 4.1 or later)
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@item Do not use Quicktime or other proprietary extension
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@item You need to convert .nib files (see next question @pxref{Tools for porting})
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@end itemize
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See also @url{http://mediawiki.gnustep.org/index.php/Writing_portable_code}
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for more information.
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@node Tools for porting, Can I transfer archived data from GNUstep to Cocoa?, How about porting between Cocoa and GNUstep?, Compatibility
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@subsection Tools for porting
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While the programming interface should be almost transparent between
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systems (expect for the unimplemented parts, of course), there are a
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variety of other files and tools that are necessary for porting
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programs.
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@table @samp
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@item ni2gmodel
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This program coverts nib files from any system, such as Cocoa or OPENSTEP to
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a gmodel format file. Gmodel can be read directly by GNUstep or you can
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convert this to a more GNUstep-native gorm format (using the Gorm interface
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modeller).
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@item Renaissance
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GNUstep Renaissance allows you to describe your user
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interfaces (that is, the windows in your application, and the buttons,
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boxes, textfields, etc in the windows) in simple and intuitive XML
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files, using an open, standard format describing the logic of the
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interface. It has a number of advantages over the proprietary nib format:
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portability, open standard, easy localization, themeability, and
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intelligent autolayout.
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@item Gorm
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The equivalent of the Interface Builder in GNUstep. It might be easier to
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just recreate the interface using Gorm rather than dealing with
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translations.
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@item OpenStep2GNUConverter and nfmake
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Two programs that allow you to convert PB files to GNUstep makefiles or
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compile a program on GNUstep directly from PB files. They probably work
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only for OPENSTEP systems and are a little out-of-date.
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@item StepTalk
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A portable scripting environment that lets your do scripting in almost
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any language you like.
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@end table
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@node Can I transfer archived data from GNUstep to Cocoa?, Does distributed objects work between GNUstep and Cocoa?, Tools for porting, Compatibility
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@subsection Can I transfer archived data from GNUstep to Cocoa?
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Apple's archiving format is proprietary and not documented, so this
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poses a problem for anyone wanting to implement compatibility with it.
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However, even if we reverse engineered the format, there are enough
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differences between the class and ivar layouts to make this sort of
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compatibility difficult. Not to mention the fact that we would
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constantly have to keep up with the changes Apple made. Also Apple's
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archiving format, as far as we know, would not be compatible between
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different machines because of endiness issues, although GNUstep doesn't
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have this problem.
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The new keyed archiving using XML file formats is much more portable,
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and GNUstep is trying to maintain compatibility with Apple with this
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type of archiving.
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@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
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@subsection Does distributed objects work between GNUstep and Cocoa?
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See the answer to the previous question (on archive compatibility) for
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why this won't work either.
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@node Is there an Interface Builder for GNUstep?, Can I use my original NIB files?, Does distributed objects work between GNUstep and Cocoa?, Compatibility
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@subsection Is there an Interface Builder for GNUstep?
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There is an Interface Builder for GNUstep called Gorm. A lot of work
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has been put into it and it works very well. You can download it from
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the ftp site or via http. The Project Manager ProjectCenter is also
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available.
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@node Can I use my original NIB files?, Can one use the hybrid "Objective-C++", Is there an Interface Builder for GNUstep?, Compatibility
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@subsection Can I use my original NIB files?
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No - NeXT/Apple never documented their nib format, so GNUstep supports
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both the 'gmodel' format (which stores information as text
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(property-lists) and can therefore be edited 'by hand') and binary
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archive format (which can be edited by Gorm). There IS a conversion
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tool called nib2gmodel that can be compiled under OPENSTEP to convert
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nib files to GNUstep gmodel files.
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Newer nib files use XML format keyed archiving and may possibly be
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transportable, although differences in class and ivar layout may still
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make this difficult.
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@node Can one use the hybrid "Objective-C++", Is there a plan to support Java/YellowBox Bindings?, Can I use my original NIB files?, Compatibility
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@subsection Can one use the hybrid "Objective-C++"
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No. at present the GNU compiler (gcc) does not support
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"Objective-C++". Soon to br released gcc 4.1 will have this support, but
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it is still unclear how robust it will be.
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@node Is there a plan to support Java/YellowBox Bindings?, What if I compile GNUstep under OPENSTEP/MacOS X?, Can one use the hybrid "Objective-C++", Compatibility
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@subsection Is there a plan to support the Java/YellowBox Bindings?
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Yes. The GNustep Java library/bridge called JIGS is available now. JIGS
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is a free (LGPL) Java Interface for GNUstep; it can automatically wrap
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Objective-C libraries based on GNUstep, making them accessible directly
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to the Java programmer as if they were Java libraries. As a side effect,
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it is also possible to use the whole engine in the reverse way: JIGS
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provides a high level API to allow Objective-C programmers to start java
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virtual machines inside GNUstep Objective-C code and access java objects
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in the java virtual machine transparently, as if they were objective-C
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objects.
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@node What if I compile GNUstep under OPENSTEP/MacOS X?, Is the Objective C API for GTK related?, Is there a plan to support Java/YellowBox Bindings?, Compatibility
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@subsection What if I compile GNUstep under OPENSTEP/MacOS X?
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GNUstep uses the X-windows display postscript extension.
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The interface to that is not the same as the interface to the
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OPENSTEP/MacOS-X windows server. While someone could write a
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backend library to provide the interface, nobody has bothered to
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date.
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You can, however, use a GNUstep program with an X11 server
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running on MacOSX.
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@node Is the Objective C API for GTK related?, How about implementing parts of the Application Kit with GTK?, What if I compile GNUstep under OPENSTEP/MacOS X?, Compatibility
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@subsection Is the Objective C API for GTK related?
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No. GNUstep applications provide their GUI via the OpenStep
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API, which provides fully object-oriented access to GUI manipulation.
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The object-oriented nature of the libraries and language make it much easier
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for new users to create their own subclasses rather than simply using the
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supplied widgets as in other frameworks.
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@node How about implementing parts of the Application Kit with GTK?, , Is the Objective C API for GTK related?, Compatibility
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@subsection How about implementing parts of the Application Kit with GTK?
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Yes and No - The GNUstep architecture provides a single,
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platform-independent, API for handling all aspects of GUI interaction
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(implemented in the gstep-gui library), with a backend architecture
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that permits you to have different display models (display postscript,
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X-windows, win32, berlin ...) while letting you use the same code
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for printing as for displaying. Use of GTK in the frontend gui
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library would remove some of those advantages without adding any.
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That being said, a backend library could be implemented using gtk
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if anyone wanted to do so. Since the frontend library handles most
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of the work involved in implementing the OpenStep API, the backend
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is a relatively thin layer and the advantages of GTK over direct
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xlib or win32 calls is likely to be minimal. If/when GTK is ported
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to more systems, a backend written using it could be a valuable
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asset - volunteers are, as always, welcome.
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@c ****************************************************************
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@c Compiling
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@node Compiling and Developing, GNU Objective C Compiler and Runtime, Compatibility, Top
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@section Compiling and Developing
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@menu
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* How can I get started programming?::
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* How can I help with GNUstep?::
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* Helping develop GNUstep::
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* Helping document GNUstep::
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* How do I assign my contribution?::
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* How do I update the task list?::
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* How do I start writing tests?::
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* How do I start writing applications?::
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* How can I help with the GNUstep website?::
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* Why doesn't GDB support Objective-C?::
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@end menu
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@node How can I get started programming?, How can I help with GNUstep?, Compiling and Developing, Compiling and Developing
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@subsection How can I get started programming?
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Good question. Read the tutorials at the GNUstep web site. Also look at
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Apple's documentation (pointers in the Resources section on the GNUstep web
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site.)
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@node How can I help with GNUstep?, Helping develop GNUstep, How can I get started programming?, Compiling and Developing
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@subsection How can I help with GNUstep?
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@enumerate
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@item Write/debug library code
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@item Write documentation
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@item Update the task list and library headers
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@item Write applications
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@end enumerate
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Let people know what you are doing. Break your project up into
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the smallest units you can. Feed back frequent updates to the
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maintainers. Ask questions in the discussion mailing list.
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Do remember that any changes beyond a few lines of code (or
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documentation) require a disclaimer or copyright assignment to the
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Free Software Foundation before they can be incorporated into the
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project. Get in touch with the GNUstep maintainer about this.
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Don't start with large-scale reorganization of anything - instead,
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get a general idea in mind of what you want to do, and proceed as
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much as possible with incremental changes that don't break anything
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- that way you can make those incremental changes available to the
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rest of the community at frequent intervals.
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Don't be afraid to give up - there is no shame in finding out that
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you have take on too large/complex a project. It's much better to
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'resign' and take on a smaller job than to just stop without telling
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anyone.
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Please document the code you add or change (using autogsdoc comments
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that begin with a slash and two asterices). But PLEASE, do not copy from
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the Apple documentation or any other copyrighted documentation.
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@node Helping develop GNUstep, Helping document GNUstep, How can I help with GNUstep?, Compiling and Developing
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@subsection Helping develop GNUstep
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There is plenty of unimplemented stuff in the gui library and
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backend libraries that volunteers can work on - just browse through
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the code and see if it conforms to the documentation.
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Specific tasks are noted in the developers section on the GNUstep
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website.
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Once you have coded something, you could always write a testcase
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and documentation for it :-)
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@node Helping document GNUstep, How do I assign my contribution?, Helping develop GNUstep, Compiling and Developing
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@subsection Helping document GNUstep
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All class documentation is written directly in the source code itself
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and translated using the autogsdoc program. See the source code and
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documentation for autogsdoc for information on documenting the classes.
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Newcomers could write documentation for individual classes by
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comparing the OpenStep specification, the MacOS-X documentation,
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and the GNUstep source. Documentation should clearly note where
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individual methods are specific to OpenStep, MacOS-X or are GNustep
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extensions.
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More experienced people could write documentation on general
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programming topics, and tutorials for new users.
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Anyone willing to write documentation, either tutorials for using
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GNUstep, or reference documentation for individual classes, should
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either write it in gsdoc or as plain ascii text for someone else to
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format into gsdoc.
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GNUstep documentation should have copyright assigned to the Free
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Software Foundation.
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@node How do I assign my contribution?, How do I update the task list?, Helping document GNUstep, Compiling and Developing
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@subsection How do I assign my contribution?
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Everyone who contributes more than 20 lines of code or so needs to
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sign a copyright assignment so that the FSF can have legal control of
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the copyright. This makes it easier to defend against any copyright
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infringement suits. Contact the GNUstep maintainer for instructions
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on how to do this or download and fill out the form
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@url{http://www.gnustep.org/resources/request-assign.future}
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(instructions are included).
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@node How do I update the task list?, How do I start writing tests?, How do I assign my contribution?, Compiling and Developing
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@subsection How do I update the task list?
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The task list (@url{http://savannah.gnu.org/pm/?group_id=99}) is
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supposed to tell people what jobs are waiting to be done. Feel free to
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add to it or update the tasks that are there (you need to create a login
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for yourself first).
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One job of major importance that pretty much anyone can do is to
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look for jobs to add to the task list. In the case of methods from
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the OpenStep specification or the MacOS-X documentation not being
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present in the GNUstep libraries, it is also helpful to add the
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method prototypes to the library header files.
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Send any changes or additions to @email{bug-gnustep@@gnu.org}.
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A beginner can look through the MacOS-X documentation, the OpenStep
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specification and the GNUstep source and contribute task items.
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If a class or method is in MacOS-X and OpenStep but is not in
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GNUstep - it's a high priority TODO and should at least be added
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to the GNUstep headers and a dummy version added to the source with
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a FIXME comment.
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If a class or method is in MacOS-X but not OpenStep or GNUstep -
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it's a low priority TODO. It should be added to the GNUstep headers
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bracketed in @code{#ifndef STRICT_OPENSTEP}
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If a class or method is in OpenStep but not in MacOS-X or GNUstep
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- it's a low priority TODO. It should be added to the GNUstep
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headers bracketed in @code{#ifndef STRICT_MACOS_X}
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There are a couple of people working on this already, so it's a
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good idea to get in touch with Adam or Richard to coordinate efforts.
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@node How do I start writing tests?, How do I start writing applications?, How do I update the task list?, Compiling and Developing
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@subsection How do I start writing tests?
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You can write testcases - where the libraries fail tests, you
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could either fix the problem, or add it to the task list.
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To write testcases, you need to use svn to install the latest
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GNUstep sourcecode you can find. Then checkout the
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'gnustep/tools/testsuite' module from svn.
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@node How do I start writing applications?, How can I help with the GNUstep website?, How do I start writing tests?, Compiling and Developing
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@subsection How do I start writing applications?
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You can either look at the links on the GNUstep website for
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applications that have been started, and email their owners to
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volunteer to help, or you can start your own project.
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@node How can I help with the GNUstep website?, Why doesn't GDB support Objective-C?, How do I start writing applications?, Compiling and Developing
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@subsection How can I help with the GNUstep website?
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Talk to Adam Fedor @email{fedor@@gnu.org}, the maintainer.
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The GNUstep website is kept as a CVS module, but the largest portions
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of it (the FAQ and the Documentation) are actually
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generated from files in the individual GNUstep packages.
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If you want to update the FAQ or documentation - grab
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the latest snapshot of the GNUstep core you can find, update it
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from the svn repository, and work with the contents of the appropriate
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documentation directory.
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If you want to work on other parts of the website, you can grab a copy
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of the website via anonymous CVS. See
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@url{http://savannah.gnu.org/cvs/?group_id=99} for instructions on how
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to do that.
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The main task with the website is to figure out which bits are
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out-of-date (or wrong) and update/mark-as-outdated as required.
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@node Why doesn't GDB support Objective-C?, , How can I help with the GNUstep website?, Compiling and Developing
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@subsection Why doesn't GDB support Objective-C?
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Um, it does. As of GDB 6.0, gdb supports debugging of Objective-C
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code.
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@c -------------------------------------------------------------------
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@node GNU Objective C Compiler and Runtime, GNUstep Base Library, Compiling and Developing, Top
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@section GNU Objective C Compiler and Runtime
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@menu
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* What is the Objective C Runtime?::
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@end menu
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@node What is the Objective C Runtime?, , GNU Objective C Compiler and Runtime, GNU Objective C Compiler and Runtime
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@subsection What is the Objective C Runtime?
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The Objective C Runtime Library provides C functions and data structures
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required to execute an Objective C program.
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The GNU Objective C Runtime Library offers everything NeXT's runtime
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does, including Categories, Protocols, @samp{+poseAs:}, thread-safety,
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class initialization on demand, delayed loading of classes, and
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initialization of static instances (such as @@""-style string objects).
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It also has several differences over NeXT's implementation:
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@itemize @bullet
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@item GNU's runtime provides ``selector-types'' along with each
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selector; NeXT's does not. A selector-type is a string that describes
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the C variable types for the method's return and argument values. Among
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other uses, selector-types is extremely helpful for fast distributed
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objects implementations, (see GNUstep Base Library Section, below).
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@item Many of the GNU functions have different names than their
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corresponding NeXT functions; the GNU names conform to the GNU coding
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standards. The GNUstep base library contains a compatibility header that
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works with both runtimes. You should use functions there or use OpenStep
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Foundation methods/functions instead of the basic
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runtime functions so that you code can run with either system.
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Apple has recently added new functionality to their runtime, including
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built-in exception handling, etc. Hopefully these will be ported to the
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GNU runtime in the future.
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@end itemize
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@c ------------- GNU Compiler and Objective C Runtime Library -------
|
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|
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@node GNUstep Base Library, GNUstep GUI Library, GNU Objective C Compiler and Runtime, Top
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@section GNUstep Base Library
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|
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@menu
|
|
* What is the GNUstep Base Library?::
|
|
* What is base's current state of development?::
|
|
* What are the features of GNU Distributed Objects?::
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|
@end menu
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@node What is the GNUstep Base Library?, What is base's current state of development?, GNUstep Base Library, GNUstep Base Library
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|
@subsection What is the GNUstep Base Library?
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|
|
|
The GNUstep Base Library is a library of general-purpose, non-graphical
|
|
Objective C objects. For example, it includes classes for strings,
|
|
object collections, byte streams, typed coders, invocations,
|
|
notifications, notification dispatchers, moments in time, network ports,
|
|
remote object messaging support (distributed objects), event loops, and
|
|
random number generators.
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|
|
|
It provides functionality that aims to implement the non-graphical
|
|
portion of the OpenStep standard (the Foundation library).
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|
|
|
@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?
|
|
|
|
GNUstep base is currently stable and, to the best of our knowledge,
|
|
implements all of the OpenStep functionality (except for a few classes
|
|
that we feel are not useful). It also implements most all of the new
|
|
Cocoa classes. However we do some things, like scripting, differently,
|
|
so we don't implement all the Cocoa classes.
|
|
|
|
@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?
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|
|
|
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 Apple's; be warned, however, that they are not compatible with each
|
|
other. They have different class hierarchies, different instance
|
|
variables, different method names, different implementation strategies
|
|
and different network message formats. You cannot communicate with a
|
|
Apple NSConnection using a GNU NSConnection.
|
|
|
|
Here are some differences between GNU distributed objects and Apple's
|
|
distributed objects: Apple 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
|
|
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----------------------
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|
|
|
@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 back-ends?::
|
|
@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.
|
|
Other back-ends could allow GNUstep to run on OpenGL 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 back-ends?, 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 thoroughly 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 back-ends?, , What is the current state of development of the front-end?, GNUstep GUI Library
|
|
@subsection What is the current state of development of the back-ends?
|
|
|
|
There are several backends currently available:
|
|
|
|
@table @samp
|
|
@item xlib
|
|
This backend runs on X11 and uses standard xlib
|
|
calls for implementing drawing. It works well, but is limited in many
|
|
areas due to the limitations of xlib drawing.
|
|
@item art
|
|
This is a very good backend that draws using the libart package and
|
|
freetype with near PostScript quality and functionality. It is currently
|
|
the standard backend (as long as the required libraries are installed).
|
|
@item w32
|
|
This backend works on Windows and uses basic Windows drawing
|
|
@item cairo
|
|
An up-and-coming backend. It still relies on unpublished functions in
|
|
the cairo library so using it is not for the beginner.
|
|
@end table
|
|
|
|
@c ------------------------- GNUstep GUI Library -----------------------
|
|
|
|
@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
|
|
GNU Ghostscript program developed by Aladdin Enterprises and now owned by artofcode LLC.
|
|
|
|
At one point, GNUstep was using this for display purposes. However the
|
|
development of DGS has stopped as it is too difficult to maintain and
|
|
no one wanted to work on it. Now we are using other means of drawing.
|
|
|
|
@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?
|
|
|
|
GNU contracted with Aladdin Enterprises to add some key features to GNU
|
|
Ghostscript so it could be used as a DPS server. This work has mostly
|
|
been done, although Aladdin did not completely finish the work that they
|
|
were contracted for. (Because the work took longer than specified and
|
|
was not completed, Aladdin agreed to waive approximately $10,000 in
|
|
promised fees for the work that was actually done and delivered.) DGS
|
|
works fairly well with a single context. Alpha channel and compositing
|
|
doesn't work.
|
|
|
|
@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 ---------------
|
|
|
|
@bye
|
|
\bye
|