1library-combo(7) GNUstep System Manual library-combo(7)
2
6 This manual page is about cross-compilation and fat binaries. Fat bina‐
7 ries are packages that you can supply which contain more the one binary
8 of your program (e.g. your application). So you can support multiple
9 platforms with a single package.
10 To support this your system has to be built in a non-flattened way.
12 Meaning that during the installation of gnustep-make you should have
13 selected --disable-flattened and the types of library combinations you
14 want to support, through the --with-library-combo option. With library
15 combinations we mean the Objective-C runtime, the Foundation library
16 and the Application library. For more details about this see the
17 LIBRARY-COMBO section.
18 If you installed your GNUstep system in a non-flattened way all system
20 dependend binaries are installed in subdirectories with cpu/os/library-
21 combo information. That means for instance that the gnustep-base
22 library will be installed in Library/Libraries/ix86/linux/gnu-gnu-gnu/
23 when you are on an Intel x86 system, running linux with the GNU runtime
24 for Objective-C and you installed GNUstep.
25 For each and every library-combo that you want to support you should
27 create the environment through gnustep-make, because it installs a dif‐
28 ferent config.make to support its own CC, OPTFLAGS, etc. flags.
29 LIBRARY-COMBO
31 An important issue is to let to a package the ability to deal with var‐
32 ious libraries and configurations available now:
33 Objective-C runtimes
35 In the Objective-C world there are three major runtimes: the
36 NeXT runtime, the Apple runtime and the GNU runtime (both with
37 and without garbage collection enabled). They are different in
38 several respects and a program or library that works at the run‐
39 time level should be aware of them.
40 Foundation libraries
42 There are several Foundation libraries an application or tool
43 can be written on top of: NeXT Foundation library which runs on
44 NeXTStep/OPENSTEP systems, gnustep-base, libFoundation and Apple
45 Cocoa system.
46 Graphical interfaces
48 Until now three libraries provide or try to provide OpenStep
49 compliant systems: the AppKit from NeXT, gnustep-gui and Cocoa
50 from Apple.
51 If a program wants to work with all the possible combinations it will
53 have to provide different binaries for each combination because it's
54 not possible to have a tool compiled for NeXT Foundation that runs with
55 gnustep-base or vice-versa. To summarize, a program can be compiled for
56 these combinations:
57 Objective-C runtime
59 nx (for NeXT), gnu (for GNU without garbage collection), gnugc
60 (for GNU with garbage collection), apple (for Apple)
61 Foundation library
63 nx (for NeXT), gnu (for gnustep-base), fd (for libFoundation),
64 apple (for Apple Cocoa)
65 GUI library
67 nx (for NeXT), gnu (for gnustep-gui), apple (for Apple Cocoa)
68 We'll denote the fact that an application was compiled for a certain
70 combination of the above values by using the abbreviations of the dif‐
71 ferent subsystems and placing dashes between them. For example an
72 application compiled for NeXT Foundation using NeXT AppKit will have
73 the compile attribute nx-nx-nx. An application compiled for Apple Cocoa
74 with the GNU compiler for Objective-C gnu-apple-apple and another one
75 compiled for gnustep-base using gnustep-gui under Unix will be denoted
76 by gnu-gnu-gnu. Here is a list of some of the possible combinations:
77 Runtime Foundation GUI
79 nx nx nx
80 nx fd gnu
81 gnu gnu gnu
82 gnu fd gnu
83 gnugc gnu gnu
84 gnugc fd gnu
85 apple apple apple
86 apple gnu gnu
87 Note that one can choose his/her own packages to build; it is not
89 required to have all the packages installed on the system. Not having
90 all of them installed limits only the ability to build and distribute
91 binaries for those missing combinations.
92 DIRECTORY STRUCTURE
95 For cross-compilation in a non-flattened directory structure is recom‐
96 mended, so that you can store on the same directory structure binaries
97 for different machines. The standard GNUstep filesystem layout is nor‐
98 mally used when a non-flattened directory structure is being used; this
99 is obtained with the --with-layout=gnustep option when configuring
100 gnustep-make. The entire GNUstep installation is then created inside
101 /usr/GNUstep (or another directory if you use the --prefix=... option
102 when configuring gnustep-make). Directories that contain binaries
103 (such as the Libraries directory) inside /usr/GNUstep are then set up
104 to support fat binaries as follows:
105 Libraries/
107 ix86/
108 linux-gnu/
109 gnu-gnu-gnu/
110 libgnustep-base.so
111 libgnustep-gui.so
112 gnu-fd-gnu/
113 libFoundation.so
114 libgnustep-gui.so
115 To allow the right libraries to be found, you need to source GNUstep.sh
117 before using GNUstep, and you need to start up your application by
118 using openapp, which will locate the right binary for your library
119 combo.
120 BUILDING FOR A LIBRARY-COMBO
122 The makefile package will allow the user to choose between different
123 library combinations. To specify a combination you want to compile for
124 just type:
125 $ make library_combo=library-combo
127 For instance if you want to choose to compile using the GNUstep's Foun‐
129 dation implementation and use the GNUstep GUI library on a GNU/Linux
130 machine you can do like this:
131 $ make library_combo=gnu-gnu-gnu
133 If your project requires running configure before compiling there are
135 two issues you have to keep in mind. 'configure' is used to determine
136 the existence of particular header files and/or of some specific func‐
137 tionality in the system header files. This thing is usually done by
138 creating a config.h file which contains a couple of defines like
139 HAVE_... which say if the checked functionality is present or not.
140 Another usage of configure is to determine some specific libraries to
142 link against to and/or some specific tools. A typical GNUstep program
143 is not required to check for additional libraries because this step is
144 done by the time the makefile package is installed. If the project
145 still needs to check for additional libraries and/or tools, the recom‐
146 mended way is to output a config.mak file which is included by the main
147 GNUmakefile, instead of using Makefile.in files which are modified by
148 configure. The reason for not doing this is to avoid having the make‐
149 files contain target dependencies like above, this way keeping only one
150 makefile instead of several for each target machine.
151 The makefile package is written for GNU make because it provides some
153 very powerful features that save time both in writing the package but
154 also at runtime, when you compile a project.
155 BUILDING FOR AN ARCHITECTURE
158 In order to build a project for multiple architectures you'll need the
159 development environment for the target machine installed on your
160 machine. This includes a cross-compiler together with all the addi‐
161 tional tools like the assembler and linker, the target header files and
162 all the libraries you need.
163 The GNUstep makefile package should be able to compile and link an
165 application for another machine just by typing
166 $ make target=target-triplet
168 where target-triplet is the canonical system name as reported by con‐
170 fig.guess.
171 USING A LIBRARY-COMBO
174 When you use library-combos, you must always source GNUstep.sh. That
175 allows you to switch library paths on the fly. If you want to switch to
176 a different library-combo in your shell, and if you are using bash,
177 it's common to first source GNUstep-reset.sh to reset all shell vari‐
178 ables, then to source GNUstep.sh again. Let's assume we use gnu-gnu-gnu
179 as our current LIBRARY_COMBO and we want to switch to gnugc-gnu-gnu,
180 then we would use:
181 . /usr/GNUstep/System/Library/Makefiles/GNUstep-reset.sh
183 export LIBRARY_COMBO=gnugc-gnu-gnu
184 . /usr/GNUstep/System/Library/Makefiles/GNUstep.sh
185
188 debugapp(1), GNUstep(7), gnustep-config(1), openapp(1)
189
192 Work on gnustep-make started in 1997 by Scott Christley <scottc@net-
193 community.com>.
194 Version 2.0.0 of gnustep-make introduced many changes with previous
196 releases, which was mainly the work of Nicola Pero <nicola.pero@meta-
197 innovation.com>
198
201 This man-page was written by Dennis Leeuw <dleeuw@made-it.com> based on
202 the DESIGN document from the gnustep-make source tree.
203
206 The DESIGN document was written by Ovidiu Predescu.
207 This work could only be as is due to the notes and corrects from Nicola
209 Pero <nicola.pero@meta-innovation.com>.
210
213 Copyright (C) 2007 Free Software Foundation, Inc.
214 Copying and distribution of this file, with or without modification,
216 are permitted in any medium without royalty provided the copyright
217 notice and this notice are preserved.
218gnustep-make 20/12/2007 library-combo(7)