@c This is a generic INSTALL file for utilities distributions.
@c If this package does not come with, e.g., installable documentation or
@c data files, please ignore the references to them below.

@c set the vars GNUSTEP_BASE_VERSION and GNUSTEP_BASE_GCC_VERSION
@include version.texi

@node Top, Introduction, (dir), (dir)

@menu
* Introduction::                
* Configuration::               
* Reading Command-Line Arguments::  
* FFI Library::                 
* Compilation::                 
@end menu

@node Introduction, Configuration, Top, Top
@section Introduction

If you are installing this package as part of the GNUstep core
libraries, read the file GNUstep-HOWTO for more complete instructions on
how to install the entire GNUstep package (including this library).
GNUstep-HOWTO comes with the core distribution and also is located at the
same ftp sites as this library.

If you are instsalling the GNUstep libraries individually, make sure you
have installed the GNUstep Makefile package (gstep-make) already. Most of
the installation instructions for gstep-make also apply to this
library. When you configure this library, make sure you use the same
configuration options as with gstep-make. Some additional options to
configure are described below.

@node Configuration, Reading Command-Line Arguments, Introduction, Top
@section Configuration

Configuration is performed by running the @file{configure} program at a
shell prompt. You may want to use some of the optional arguments to the
@file{configure} program. Type @code{configure --help}
for a list of these. It is not likely that you will need to use the
@code{--prefix} option, since gstep-base will automatically install in
the directory specified by the @code{GNUSTEP_SYSTEM_ROOT} environment
variable (specified when you installed gstep-make).

Many configuration options for the base library need to be specified
when configuring the gstep-make package. In most cases, it is a good
idea to specify the same configuration options when configuring both
packages, just to make sure.

Also make sure you've read the machine-specific instructions for your
particular operating system and CPU. These instructions come with the
core libraries and are also located at the GNUstep web site at
@url{http://www.gnustep.org}.

@menu
* Reading Command-Line Arguments::  
* FFI Library::                 
@end menu

@node Reading Command-Line Arguments, FFI Library, Configuration, Top
@section Reading Command-Line Arguments

There are two features that change how GNUstep gets access to 
command-line arguments and environment variables (normally passed to
the program in the @code{main()} function. These features are
@code{--enable-pass-arguments} and the @code{--enable-fake-main}
option(s). 

The fake-main option @emph{secretly} renames the @code{main()} function
and substitutes it's own function which stores the command line
arguments before calling the real main.

The pass-arguments option absolves GNUstep of any effort to get the
command-line arguments and instead forces the developer to insert the
line

@example
  [NSProcessInfo initializeWithArguments:argv count:argc environment:env];
@end example

in the @code{main()} function of their program.

Normally, the configure script will determine if a program
can read process information directly from the system (for use by the
class NSProcessInfo) and enable or disable the fake-main hack
automatically, but if you find that configure is not doing this
correctly, you can force the fake-main hack to be used, which will
always work. Note that if the fake-main hack is enabled, you need to
include the header file GSConfig.h in you main program -- this is done
by default if you include NSObject.h or Foundation.h. If you want to
avoid the whole idea of the fake-main hack, you can use the
pass-arguments option. In this case you will be forced to call the
NSProcessInfo initializeWithArguments method to pass the program
arguments to NSProcessInfo (This would be done automatically if you use
the NSApplicationMain function in a gui application).

@node FFI Library, Compilation, Reading Command-Line Arguments, Top
@section FFI Library

GNUstep's NSInvocations and Distributed Objects code involves detailed
manipulation of function (method) calls, which does not work on all
machine architectures. A more robust and portable solution is to use a
library that implements a Foreign-Function Interface (FFI), such as the
ffcall libraries. If you use a non-x86 machine, you should seriously
consider enabling this option using @code{--enable-ffcall}.

For this to work, you need to have the ffcall libraries, which you can
get from @url{ftp://ftp.santafe.edu/pub/gnu/} or
@url{http://clisp.cons.org/~haible/}. You also need to have a special
version of the Objective-C library (as of gcc 2.95.x the required hooks
are not in the standard library). You can get this library from
@url{ftp://www.gnustep.org/pub/gnustep/contrib/libobjc-hh.tar.gz} or
patch the standard library with the patch at
@url{ftp://www.gnustep.org/pub/gnustep/contrib/libobjc-ffi.patch}.

Make sure you specify this option when configuring gstep-make also.

@node Compilation,  , FFI Library, Top
@section Compilation

To compile this library, type make. After this is complete, type make
install (make sure you are the root user). Some additional options you
can use with make are @samp{debug=yes} to make a debugging version of
the library and @samp{shared=no} to make a static version of the
library. See the gstep-make package for more information on these options.


@bye