gnustep-userfaq.texi

\input texinfo   @c -*-texinfo-*-
@c A FAQ for GNUstep Users

@node Top, GNUstep General Information, (dir), (dir)
@chapter GNUstep Frequently Asked Questions for Users

Last updated @today{}.
Please send corrections to @email{gnustep-maintainer@@gnu.org}. Also look
at the (developer) FAQ for more developer oriented questions.

@menu
* GNUstep General Information::  
* Compiling and Installing::    
* Compatibility and Layout::    
* Troubleshooting::             
@end menu

@node GNUstep General Information, Compiling and Installing, Top, Top
@section GNUstep General Information

@menu
* What is GNUstep?::            
* What is the OpenStep standard?::  
* What platforms does GNUstep run on?::  
* Does GNUstep run on Windows?::  
* What is GNUstep's position towards KDE and the GNOME project?::  
* How can I get GNUstep?::      
* How do you run GNUstep?::     
* Is there a web site?::        
* When is GNUstep intended to be available?::  
* What is usable?::             
@end menu

@node What is GNUstep?, What is the OpenStep standard?, GNUstep General Information, GNUstep General Information
@subsection What is GNUstep?

GNUstep is the Free Software Foundation's effort to implement NeXT
Software, Inc.'s (now Apple Computer, Inc.) OpenStep Standard.  Also we
are building developer and user applications based on this standard which
may someday be used to form a complete desktop experience.

@node What is the OpenStep standard?, What platforms does GNUstep run on?, What is GNUstep?, GNUstep General Information
@subsection What is the OpenStep standard?

OpenStep is an Application Programming Interface (API) for creating
applications using the Objective-C language.  It was published by NeXT
Computer, Inc. in 1994.

OpenStep consists of three parts: the @samp{Foundation Kit}, a library
of non-graphical objects; the @samp{Application Kit}, a library of
objects useful in creating graphical applications; and the @samp{Display
PostScript System} (DPS), an interface for drawing to the screen using
the PostScript graphics language. DPS support is not being persued at
this time however.

You can obtain a copy of the OpenStep standard from the GNUstep web site
@url{http://www.gnustep.org} or it's mirror sites.

@node What platforms does GNUstep run on?, Does GNUstep run on Windows?, What is the OpenStep standard?, GNUstep General Information
@subsection What platforms does GNUstep run on?

See the list of supported platforms at
@url{machines_toc.html} for
information on what machines GNUstep builds on and what the status of
the ports is. Probably a few days porting to any other UNIX system where
current gcc compilers and gdb debugger work.

@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 system-based platforms such
as GNU/Linux and FreeBSD.

That being said, the base library should run on Windows NT, 98, 2000, and XP
with the Cygwin UNIX system-emulation environment from Cygnus
(@url{http://www.cygwin.com/}), or the MinGW environment
(@url{http://www.mingw.org}).  

The GUI library uses the win32 backend library to work under
Windows.  The backend library is a thin layer that converts the
GNUstep methods to handle drawing of GUI elements to calls to the
Windows API.  This project is currently in beta.

@node What is GNUstep's position towards KDE and the GNOME project?, How can I get GNUstep?, 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 super-set of C), and when 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 How can I get GNUstep?, How do you run GNUstep?, What is GNUstep's position towards KDE and the GNOME project?, GNUstep General Information
@subsection  How can I get GNUstep?

Many distributions include packaged versions of GNUstep (Debian,
etc). To compile from sratch, download the GNUstep Startup package or
get the HOWTO from @url{gnustep-howto_toc.html}. Get the latest releases
from @url{ftp://ftp.gnustep.org/pub/gnustep/core}.

@node How do you run GNUstep?, Is there a web site?, How can I get GNUstep?, GNUstep General Information
@subsection  How do you run GNUstep?

 You are presumably under the misapprehension that GNUstep is
some sort of program or window manager.

It isn't.

GNUstep is a whole load of things --- primarily a set of libraries
for developing software.

At present, it's those libraries, plus various command-line based
support tools and service providing daemons, plus various GUI
development tools, a GUI desktop/workspace application, etc.

At no stage will you ever 'run' GNUstep --- you will run applications
and tools and will make use of it's services. At some point
you may well find packages distributed as 'GNUstep' systems in the
way that you get 'GNU/Linux' systems packaged today. Look at
Simply GNUstep @url{http://simplygnustep.sourceforge.net/} for instance.

If you want to see a sample GUI application running you need to build
GNUstep and look at the example applications in the gnustep-examples
package.  Build 'Finger' or 'Ink' and start it with 'openapp Finger.app'
or 'openapp Ink.app'

To look best, use WindowMaker (the currently preferred GNUstep
window manager) as your window manager.

@node Is there a web site?, When is GNUstep intended to be available?, How do you run GNUstep?, GNUstep General Information
@subsection  Is there a web site?

See @url{http://www.gnustep.org/}.

@node When is GNUstep intended to be available?, What is usable?, Is there a web site?, GNUstep General Information
@subsection  When is GNUstep intended to be available?

It's usable now. Major releases are made about every six months. However, if
you are a serious developer, it's probably best to use the latest
snapshots.

@node What is usable?,  , When is GNUstep intended to be available?, GNUstep General Information
@subsection  What is usable?

Most of GNUstep is quite usable and there are many complex applications
that work well. However, GNUstep does not completely track the latest
changes that Apple makes to their interface and there are still some
parts that need some work).

What does this mean for users? Many applications will run quite well.
Applications that require very complex text handling and some unusual
features and/or some of the latest additions to Cocoa may not work as
well.

@c ****************************************************************
@node Compiling and Installing, Compatibility and Layout, GNUstep General Information, Top
@section Compiling and Installing

@menu
* How do I compile GNUstep on my machine? ::  
* Are there any precompiled packages available?::  
* What are these type and size warnings?::  
* What are these import warnings?::  
@end menu

@node How do I compile GNUstep on my machine? , Are there any precompiled packages available?, Compiling and Installing, Compiling and Installing
@subsection How do I compile GNUstep on my machine?

Read the file @file{GNUstep-HOWTO}, which comes with the GNUstep
distribution (gnustep-make), and also is available separately on the
GNUstep web site.

@node Are there any precompiled packages available?, What are these type and size warnings?, How do I compile GNUstep on my machine? , Compiling and Installing
@subsection Are there any precompiled packages available?

Check @url{http://www.gnustep.org/resources/sources.html} for links to
RPMs, Debian packages, and BSD ports. There's also Windows installers, Mac OS X
binaries and others.

@node What are these type and size warnings?, What are these import warnings?, Are there any precompiled packages available?, Compiling and Installing
@subsection What are these type and size warnings?

These warnings:
@example
/usr/bin/ld: warning: type and size of dynamic symbol
`__objc_class_name_NSConstantString' are not defined
@end example

are a common occurence and are due to a mismatch between gcc and
ld. They don't do any harm so they can be safely ignored. They have been
fixed in GCC version 3.1.

@node What are these import warnings?,  , What are these type and size warnings?, Compiling and Installing
@subsection What are these import warnings?

Do you get this obnoxious warning whenever you compile an application, tool,
or Objective-C program:

@example
warning: using `#import' is not recommended
[...]
@end example

Up until gcc 3.4, the #import directive was not implemented correctly.
As a result, the GCC compiler automatically emitted a warning whenever
#import was used.  As of gcc 3.4, this problem has been fixed, so
presumably, this warning is no longer emitted when code is compiled. If
you are using an early compiler, you can supress these warnings by adding
@code{-Wno-import} to your include (cpp) flags.

@c ****************************************************************
@node Compatibility and Layout, Troubleshooting, Compiling and Installing, Top
@section Compatibility and Layout

@menu
* Can I run NeXT OPENSTEP or Mac OS X programs on GNUstep?::  
* Is GNUstep following changes to OpenStep and Mac OS X?::  
* Do we have to have the NEXTSTEP look and feel?::  
* What's up with the directory structure?::  
* Why not use framework bundles?::  
@end menu

@node Can I run NeXT OPENSTEP or Mac OS X programs on GNUstep?, Is GNUstep following changes to OpenStep and Mac OS X?, Compatibility and Layout, Compatibility and Layout
@subsection Can I run NeXT OPENSTEP or Mac OS X programs on GNUstep?

You can't run these programs on GNUstep, but if you have the source
code for the programs, you should be able to port them to GNUstep and
compile them. Whether or not you will be able to run them depends on how
complete GNUstep is at the time.

@node Is GNUstep following changes to OpenStep and Mac OS X?, Do we have to have the NEXTSTEP look and feel?, Can I run NeXT OPENSTEP or Mac OS X programs on GNUstep?, Compatibility and Layout
@subsection  Is GNUstep following changes to OpenStep and Mac OS X?

Yes, gnustep-base already contains the documented changes in the
Foundation library.  GNUstep aims to be compatible with both the
OpenStep specification and with Mac OS X. It should be easy to write
an application that compiles cleanly under both GNUstep and Cocoa.

@node Do we have to have the NEXTSTEP look and feel?, What's up with the directory structure?, Is GNUstep following changes to OpenStep and Mac OS X?, Compatibility and Layout
@subsection  Do we have to have the NEXTSTEP look and feel?

GNUstep is aiming for something like the NEXTSTEP 3.3 look and feel.
Although we don't want to force anyone into this, a lot of the power and
ease of use comes from this feel. The look of GNUstep is something
different --- buttons and other widgets can look different but still act
the same way. We hope to implement themes which will allow
this.

@node What's up with the directory structure?, Why not use framework bundles?, Do we have to have the NEXTSTEP look and feel?, Compatibility and Layout
@subsection What's up with the directory structure?

First of all, GNUstep uses a slightly different directory structure than
NEXTSTEP or Mac OS X. Part of this is historical, part is because we can't do
things the same way (see @pxref{Why not use framework bundles?}). Although
currently the structure is very similar to the one used in Mac OS X.

@node Why not use framework bundles?,  , What's up with the directory structure?, Compatibility and Layout
@subsection Why not use framework bundles?

Framework bundles are much more difficult to port and to use, and are very
unnatural on a UNIX system; extremely unnatural on Windows. In a
framework bundle, the shared dynamic library is inside a framework wrapper
directory.  Because of this, the dynamic linker can't find it.

We have frameworks, so how do we work around that? Well, we build dynamic
links from a directory inside the dynamic linker path into the framework,
which work, but then you can't move the framework anywhere else on
the system, otherwise you break the link, and nothing will find the
framework any longer!

On systems without dynamic links, like Windows, we can't even do this!  
We have to copy the library from the framework into the dynamic linker
path, but that is simply a shared library then!  Absolutely @emph{no}
difference.  You put the dynamic library in a system directory in the
dynamic linker path, and associate with that library a resource directory.

OpenStep for Windows did that, and still called them frameworks.  
So we can do the same, and call our libraries frameworks. 

In a shared library, the shared dynamic library is in a directory which is
in the path to the dynamic linker.  the dynamic linker can find it very
easily.  this is how all shared and static libraries work on UNIX systems,
Windows systems and possibly most system at all.

Moreover, the OpenStep API requires us to provide some stuff for
frameworks, like creating and registering automatically a framework
object each time a framework is used (linked at runtime, or linked into
the app), and attaching to it the list of classes inside the framework -
which are not particularly trivial to implement --- they depend on playing
with the linker and the object file format --- and might produce troubles
when porting. And we never use these facilities.

For Apple Mac OS X sure it's easier. They can modify
the system linker, compiler, the system dynamical linker. They
always know on which platform they are working (their own), etc.  They can
modify the system to support frameworks natively.  Easy that way.

But GNUstep is meant to run on many different platforms, platforms which
we don't control (Windows, Sun Solaris, Darwin, GNU/Linux, UNIX system
variants) and which have different linkers and do not support frameworks
natively.  On some systems it's difficult to just load a bundle or
compile a shared library!

So building the core libraries as 'libraries' means that it's much
easier to port them, and it's much more difficult to break them.

Sure, frameworks have a bundle of resources associated with it --- but we
can very easily associate a bundle of resource with a shared library, no
reason why not.  We are doing it.  

So please note that GNUstep libraries are meant to be much similar to
Mac OS X frameworks.  They are composed of a shared library and
associated with a bundle of resources.  There is a difference in
terminology, in where the resources are installed, and possibly a slight
difference in the NSBundle API to get to the resource bundle (anyway,
it's a one line difference between Mac OS X and GNUstep, so it looks like
very easy to #ifdef).

In other words, GNUstep libraries are meant to basically do the same as
frameworks do on Mac OS X, but to be portable to very different platforms (such
as Windows).


@c ****************************************************************
@node Troubleshooting,  , Compatibility and Layout, Top
@section Troubleshooting

@menu
* Problems compiling (loading shared libs)::  
* Problems compiling (GNUstep Internal Error)::  
* Problems running tools and compiling::  
* Problems with gcc3::          
* Problems with Alt key::       
* Problems with fonts::         
* No characters displayed::     
* No Makefile::                 
@end menu

@node Problems compiling (loading shared libs), Problems compiling (GNUstep Internal Error), Troubleshooting, Troubleshooting
@subsection Problems compiling (loading shared libs)

If you get something like

@example
plmerge: error while loading shared libraries:
libgnustep-base.so.1: cannot open shared object file: No such file or directory
@end example

or this:

@example
Making all for service example...
make[2]: *** [example.service/Resources/Info-gnustep.plist] Error 1
make[1]: *** [example.all.service.variables] Error 2
make[1]: Leaving directory `/home/multix/gnustep-gui-0.8.6/Tools'
make: *** [internal-all] Error 2
@end example

This means your GNU make is being overly protective. When you try to
become root (e.g. to install something), certain environment variables
like LD_LIBRARY_PATH are unset in order to reduce the possibility of
a security breach.  If you are becoming root to install
something, you need to exec the GNUstep.sh file as root, just as you
do when you login. Although for simplicity, you can also try this:

@example
make LD_LIBRARY_PATH=$LD_LIBRARY_PATH
@end example

You could also be having problems with gcc. gcc 2.96 does not work
(Mandrake 8.1, perhaps others). Use a different compiler, like gcc 3.x.

@node Problems compiling (GNUstep Internal Error), Problems running tools and compiling, Problems compiling (loading shared libs), Troubleshooting
@subsection Problems compiling (GNUstep Internal Error)

If you get

@example
GNUSTEP Internal Error:
The private GNUstep function to establish the argv and environment
variables was not called.
Please report the error to bug-gnustep@@gnu.org.
@end example

when compiling the gui library, there could be several things wrong. One
is that you installed the gnustep-objc library, but the compiler
found another Objecive-C library (like the one that came with gcc). If
you are using gcc 3.x, DO NOT use the gnustep-objc library. 

There could also be a mismatch between the base and gui library versions.
Make sure you have the latest release of each library installed.


@node Problems running tools and compiling, Problems with gcc3, Problems compiling (GNUstep Internal Error), Troubleshooting
@subsection Problems running tools and compiling

If you have a system that has SELinux enabled (Fedora Core for example),
you may have trouble running and/or compiling (some tools are run during
the compilation process) GNUstep. This is due to the use of ffcall
and/or libffi and other techniques used to access memory in a way that
SELinux does not like. You might get errors like

@example
trampoline: cannot make memory executable
/bin/sh: line 5:  8427 Aborted                 ././shared_obj/ 
make_services --test GSspell.service/Resources/Info-gnustep.plist
gmake[2]: *** [GSspell.service/Resources/Info-gnustep.plist] Error 1
@end example
or
@example
libgnustep-base.so.1.13: cannot restore segment prot after reloc: Permission denied
@end example

If you are using ffcall, you might need to switch to libffi. But in
either case, it might help to do this:

@example
chcon -t texrel_shlib_t /usr/GNUstep/System/Library/Libraries/*.so
@end example

after installing the base libraries.

@node Problems with gcc3, Problems with Alt key, Problems running tools and compiling, Troubleshooting
@subsection Problems with gcc3

Don't forget you need to update binutils and libc also.

@node Problems with Alt key, Problems with fonts, Problems with gcc3, Troubleshooting
@subsection Problems with Alt key

It's possible the Alt key is not where you think it is or is defined
incorrectly. Try running the GSTest application, KeyboardInput test
(located in the examples package 
at @url{ftp://ftp.gnustep.org/pub/gnustep/core}) to test it.
See
@url{http://www.gnustep.org/resources/documentation/User/Gui/KeyboardSetup.html}
for information on how to change the settings.

If you are using WindowMaker, it's possible it is grabing this key and
using it for itself. To check, open Window Maker's WPrefs and go to the
Mouse Preferences. Then use another value for the "Mouse grab modifier"
(bottom right). That will allow you to alt-drag things.

@node Problems with fonts, No characters displayed, Problems with Alt key, Troubleshooting
@subsection Problems with fonts

Why do the characters get changed to asterisks ('*')?

The problem you are getting come from the fact that the xlib backend
 (when not using Xft) will only use one fixed X font for a given
font name. If the font "helvetica" is used inside of GNUstep the
one selected X font, in your case
"-*-helvetica-medium-r-normal--12-*-*-*-p-*-iso8859-1" is used. So
only characters (or glyphs) that are available in that font can be
displayed. The selection of which font name to use happens inside the
font_cacher and is more or less at random (the order fonts are
listed by the X system).

You can influence the fonts that are available by setting:

@example
defaults write NSGlobalDomain GSFontMask "*iso8859-13"
font_cacher
@end example

(or using a different character set, like iso8859-2). This is really a
bug in GNUstep, but it hasn't been fixed yet.

The other option is the use the art backend, which handles fonts much
better. When compiling gnustep-back, start with

@example
./configure --enable-graphics=art
@end example

@node No characters displayed, No Makefile, Problems with fonts, Troubleshooting
@subsection No characters displayed.

When using the xlib backend, no characters are displayed in any GNUstep
applications.

The xlib backend has font anti-aliasing turned on by default. It's possible
that GNUstep can't find any fonts on your system that can be properly anti-
aliased. Try

@example
defaults write NSGlobalDomain GSFontAntiAlias NO
@end example

to turn off font anti-aliasing.

@node No Makefile,  , No characters displayed, Troubleshooting
@subsection No Makefile

I tried to compile something and I get:

@example
GNUmakefile:27: /Makefiles/common.make: No such file or directory 
GNUmakefile:39: /Makefiles/aggregate.make: No such file or directory 
gmake: *** No rule to make target `/Makefiles/aggregate.make'.  Stop. 
@end example

Make sure you have installed the gnustep-make package and also type:

@example
source /usr/local/share/GNUstep/Makefiles/GNUstep.sh
@end example

You can put this line in your @file{.profile} or @file{.bash_profile} file
so that it is done automatically when you log in.

@bye
\bye