path: root/configure.texi

\input texinfo    @c -*-para-*-
@c %**start of header
@setfilename configure.info
@settitle Cygnus Configure
@c %**end of header
@c @setchapternewpage odd

@titlepage
@sp 10
@title{Cygnus Configure}
@author{K. Richard Pixley}
@page
@vskip 0pt plus 1filll
Copyright @copyright{} 1991 Cygnus Support
@end titlepage

@ifinfo
This document attempts to describe the configuration system used and
distributed by Cygnus Support.

Copyright @copyright{} 1991 Cygnus Support
@end ifinfo

@ifinfo
@node top, Invoking, (dir), (dir)
@top top

This file documents the configuration system used and distributed by
Cygnus Support.

NOTE: support for a Cygnus experimental option, @code{-subdirs} is at
least temporarily suspended.  Most of the code is still in configure but
the option is disabled.  This document describes that feature, but those
parts are prominently marked with NOTE's like this one. FIXME-soon

@menu
* Invoking::			Invoking
* Using Configure::		Using Configure
* What Configure Does::		What Configure Does
* Porting::			Porting with Configure
* Known Bugs::			Known Bugs
* Variables Index::		Variable Index
* Concept Index::		Concept Index

 --- The Detailed Node Listing ---

Using Configure

* Install Locations::		Where to install things once they are built
* Build Directories::		Where to build object files
* Host::			Telling @code{configure} what will source will
			  be built
* Target::			Telling @code{configure} what the source will
			  target
* Local Conventions::		Adding information about local conventions

Install Locations

* prefix::			Changing the default install directory
* datadir::			How to separate host independent files
			  from host dependent files when
			  installing for multiple hosts
* Install Details::		Full descriptions of all installation
			  subdirectories

Porting with Configure

* Native Ports::		Native Ports
* Adding Hosts Or Targets::	Adding Hosts Or Targets
* Reference::			Reference

Native Ports

* Add A Host::			Add A Host
* Port An Existing Target::	Port An Existing Target
* Add A Target::		Add A Target
* Build Host & Target::		Build Host & Target
* Build New Target On Some Other Host::	 Build New Target On Some Other Host

Adding Hosts Or Targets

* Add Canonical Triple To Config.Subr (Cf Config.Subr)::  Add Canonical Triple To Config.Subr (Cf Config.Subr)
* (Optional) Add Alias (Cf Config.Subr)::  
* Monte Carlo - Configure ; Make::  Monte Carlo - Configure ; Make
* Remedies::			Remedies
* Adding Configure To Existing Programs::  Adding Configure To Existing Programs

Remedies

* Automagic Config::		Automagic Config
* Symlinked Files::		Symlinked Files
* Makefile Fragments (Cf Configure.In)::  Makefile Fragments (Cf Configure.In)

Adding Configure To Existing Programs

* Makefile Support::		Makefile Support
* Add Standard Macros (Template Follows)::  Add Standard Macros (Template Follows)

Adding Configure To Existing Programs

* Makefile Host Support - Move It To Host Fragments::  Makefile Host Support - Move It To Host Fragments
@end menu
@end ifinfo

@node Invoking, Using Configure, top, top
@chapter Invoking

The usual way to invoke @code{configure} is as follows:
@example
configure @var{host}
@end example
This asks @code{configure} to prepare the source to be compiled in a
@var{host} environment with programs and files to be installed in
@file{/usr/local}.

NOTE: support for multiple hosts is at least temporarily suspended.
FIXME-soon

If more than one host is specified on the command line, then
configurations are created for each and @code{-subdirs} is assumed.

@table @code

@item -datadir=@var{dir}
This option requests that the source be configured so that host
independent files will be installed in @var{dir}.

This option sets the @code{configure} variable @code{datadir}.  If
@code{datadir} is not empty, generated Makefiles will have their
@code{datadir} variables set to this value. (See @xref{Install Details}.)

@item -gas
Notifies @code{configure} that the @sc{GNU} assembler is available on
all specified hosts.

@item -help
Displays a quick summary of how to invoke @code{configure}.

@item -host=@var{host}
FIXME-soon: I don't think this option should be documented.

NOTE: support for this @code{-namesubdir=} is at least temporary
suspended. FIXME-soon

@item -namesubdir=@var{name}
Asks that any subdirectories created by the @code{-subdirs} option be
named @var{name}.  Note that using multiple hosts with
@code{-namesubdir=} isn't terribly useful.

@item -nfp
Notifies @code{configure} that all of the specified hosts have @emph{no
floating point} units.

@item -norecursion
Asks @code{configure} to configure only this directory.  Any
subdirectories are ignored.  This is used by the executable shell script
@file{config.status} to reconfigure the current directory.
(@xref{FIXME-now:config.status}.

@item -objdir=@var{dir}
This option is no longer supported.  Use @code{-srcdir=} instead.

@item -prefix=@var{dir}
This option requests that the source be configured so that programs and
files will be installed in @var{dir}.

This option sets the @code{configure} variable @code{prefix}.  If
@code{prefix} is not empty, generated Makefiles will have their
@code{prefix} variables set to this value. (See @xref{Install Details}.)

@item -recurring
This option is used internally by @code{configure} when recurring on
subdirectories.  It's sole purpose is to supress status output.  It can
be overriden with the @code{-verbose} option.

@item -rm
Asks @code{configure} to @emph{remove} a configuration rather than
create one.

@item -site=@var{site}
Asks that Makefiles be generated using site specific Makefiles for
@var{site}.  (@xref{FIXME-now: site specific Makefiles}.)

@item -srcdir=@var{_dir}
Tells @code{configure} that the sources are located in @var{dir}.  The
build directory is assumed to be @file{.}.

NOTE: support for this @code{-subdirs} is at least temporary suspended.
FIXME-soon

@item -subdirs
Asks that configurations be placed in subdirectories named
@file{H-@var{host}} of each build directory, for each host specified.
If this configuration is not native, (@var{host} is not @var{target}),
then he subdir will be named @file{X-@var{host}-@var{target}} instead.

NOTE: support for multiple targets is at least temporarily suspended.
FIXME-soon

@item -target=@var{target}
Requests that the sources be configured to target the @var{target}
machine.  If no targets are specified explicitly, the target is assumed
to be the same as the host.  If multiple targets are specified,
configurations for each are created and @code{-subdirs} is assumed.

@item -tmpdir=@var{tmpdir}
Sets the directory in which @code{configure} creates temporary files to
@var{tmpdir}.

@item -verbose
@item -v
Asks that @code{configure} print status lines for each directory
configured.  Normally, only the status lines for the current directory
are printed.

@item -x
Tells @code{configure} that @sc{MIT} style @sc{X11} header files and
libraries are available on this machine, even if they are not normally
available.

@end table

@node Using Configure, What Configure Does, Invoking, top
@chapter Using Configure

Configure prepares source directories in anticipation of building.
Source cannot be built until it has been configured.  The choices
and options available at configuration time generally have valid
defaults, but the defaults do not cover all cases.  The choices
available include:

@menu
* Install Locations::		Where to install things once they are built
* Build Directories::		Where to build object files
* Host::			Telling @code{configure} what will source will
			  be built
* Target::			Telling @code{configure} what the source will
			  target
* Local Conventions::		Adding information about local conventions
@end menu

@node Install Locations, Build Directories, Using Configure, Using Configure
@section Install Locations

@cindex Where to install

Using the default configuration, @code{make install} will create a
single tree of files, some of which are programs.  The location of this
tree is determined by the value of the variable @code{$(prefix)}.  The
default value of @code{$(prefix)} is @file{/usr/local}.  This is
probably correct for native tools installed on only one host.

@menu
* prefix::			Changing the default install directory
* datadir::			How to separate host independent files
			  from host dependent files when
			  installing for multiple hosts
* Install Details::		Full descriptions of all installation
			  subdirectories
@end menu

@node prefix, datadir, Install Locations, Install Locations
@subsection Changing the default install directory

@cindex Changing the default install directory
@cindex Prefix directory

In the default configuration, all files are installed in subdirectories
of @file{/usr/local}.  The actual location is determined by the value of
the @code{configure} variable @code{$@{prefix@}} which determines the
value of the Makefile variable @code{$(prefix)}.

You can also set the value of the Makefile variable @code{$(prefix)}
explicitly each time you invoke @code{make} if you are so inclined, but
because many programs have this location compiled in, you must specify
the @code{$(prefix)} value precisely on each invocation of @code{make}
or you will end up with a broken installation.

To make this easier, the value of the @code{configure} variable
@code{$@{prefix@}} can be set on the command line to @code{configure}
using the option @code{-prefix=}.  (See @xref{prefix}).


@node datadir, Install Details, prefix, Install Locations
@subsection Installing for multiple hosts

@cindex Configuring for multiple hosts
@cindex Sharing host independent files
@cindex The datadir directory
@cindex Installing host independent files

Host independent files are installed in subdirectories of
@file{/usr/local/lib}.  The actual location is determined by the value
of the @code{configure} variable @code{$@{datadir@}} which determines
the value of the Makefile variable @code{$(datadir)}.  By default, the
value of @code{$@{datadir@}} is @code{$@{prefix@}/lib}.  This makes
single host installs simple, and simplifies changing the default
location for the install tree, but doesn't allow for multiple hosts to
effectively share host independent files.

To configure so that multiple hosts can share common files, use
something like:

@example
configure @var{host1} -prefix=/usr/gnu/H-@var{host1} -datadir=/usr/gnu/H-independent
make all info install install-info clean
configure @var{host2} -prefix=/usr/gnu/H-@var{host2} -datadir=/usr/gnu/H-independent
make all info install install-info
@end example

The first line configures the source for @var{host1} in such a way that
host specific programs will be placed in subdirectories of
@file{/usr/gnu/H-@var{host1}} and host independent files will be placed
in @file{/usr/gnu/H-independent}.  (See @xref{datadir}.)

The second line builds and installs all programs for @var{host1},
including both host independent and host dependent files.

The third line reconfigures the source for @var{host2} in such a way
that host specific programs will be placed in subdirectories of
@file{/usr/gnu/H-@var{host2}} and host independent files will again be
placed in @file{/usr/gnu/H-independent}.

The fourth line builds and installs all programs for @var{host2}.  Host
dependent files will be installed in new directories but the host
independent files will be installed @emph{on top of} the host
independent files installed for @var{host1}.  This results in a single
copy of the host independent files suitable for use by both hosts.

NOTE: support for -subdirsa and multiple hosts is at least temporarily
suspended. FIXME-soon

Previously this was:

@example
configure @var{host1} @var{host2} -prefix=/usr/gnu
@end example

@node Install Details,  , datadir, Install Locations
@subsection Full descriptions of all installation subdirectories

In any install, a number of standard directories are created.  Their
actual names are determined by Makefile variables.  Some of the
defaults for Makefile variables can be changed at configure time using
command line options to @code{configure}.  For more information on the
standard directories or the Makefile variables, please refer to
@cite{standards.text}.

Note that @code{configure} does not create @code{srcdir} at any time.
The directory @code{srcdir} is not an installation directory.
(@xref{FIXME-now}.)

All makefile variables can be overridden on the command line to
@code{make}.  (See @xref{Overriding, Overriding Variables, Overriding
Variables, make, Make}.)  If you do so, you will need to specify the
value precisely the same way for each invocation of @code{make} or you
risk ending up with a broken installation.  This is because many
programs have the locations of other programs or files compiled into
them.  If you find yourself overriding any of the variables frequently,
you should consider site depedent Makefile fragments.  (See @xref{FIXME-now}.)

During @code{make install}, the following standard directories will be
created and populated:

@vindex prefix
@defvr {Makefile and configure} prefix
By default, the value of this variable determines the root of the
installation tree.  It may be overridden with the @code{-srcdir=}
command line option to @code{configure}.  (@xref{Invoking}.)  The
default value for @code{prefix} is @file{/usr/local}.
@end defvr

@vindex bindir
@defvr Makefile bindir
The value of this variable names a directory intended to contain binary
programs that users can run.  The default value for @code{bindir}
depends on @code{prefix} so @code{bindir} is normally changed
only indirectly through @code{prefix}.  The default value for
@code{$(bindir)} is @code{prefix}@file{/bin}.
@end defvr

@vindex datadir
@defvr {Makefile and configure} datadir
The value of this variable names a directory intended to contain host
independent files.  The @code{configure} variable, which is used to set
the default value of the Makefile variable, can be set at configure time
using the @code{-datadir=} option to @code{configure}.
(@xref{Invoking}.)  The default value for @code{datadir} is
@code{prefix}@file{/lib}.
@end defvr

@vindex libdir
@defvr Makefile libdir
The value of this variable names a directory intended to hold libraries
and support programs.  The default value for @code{libdir}
depends on @code{prefix} so @code{libdir} is normally changed
only indirectly through @code{prefix}.  The default value for
@code{libdir} is @code{prefix}@file{/lib}.
@end defvr

@vindex mandir
@defvr Makefile mandir
The value of this variable names a directory intended to hold @emph{man}
format man pages.  The default value for @code{mandir}
depends on @code{prefix} so @code{mandir} is normally changed
only indirectly through @code{prefix}.  The default value for
@code{mandir} is @code{datadir}@file{/man}.
@end defvr

@vindex man@var{N}dir
@defvr Makefile man@var{N}dir
There are eight of these variables named @code{man1dir}, @code{man2dir},
etc.  They are intended to name the specific directories which hold the
man pages of their respective sections.  That is, @code{man1dir} holds
@file{emacs.1}, the man page for the emacs program while @code{man5dir}
holds the man page describing the @code{rcs} data file format, called
@file{rcsfile.5}.  The default value for @code{man@var{N}dir}
depends on @code{prefix} so @code{man@var{N}dir} is normally changed
only indirectly through @code{prefix}.  The default value for
@code{man@var{N}dir} is @code{mandir}@file{/man@var{N}}.
@end defvr

@vindex manext
@defvr Makefile manext
The makefile variable manext is not supported by the @code{configure}.
The @sc{gnu} coding standards do not call for @code{man1ext},
@code{man2ext}, so the intended use for @code{manext} is not clear.
(See also @xref{FIXME-now:extensions}.)
@end defvr

@vindex infodir
@defvr Makefile infodir
The value of this variable names a directory intended to hold
@emph{info} format documentation.  The default value for @code{infodir}
depends on @code{prefix} so @code{infodir} is normally changed
only indirectly through @code{prefix}.  The default value for
@code{infodir} is @code{datadir}@file{/info}.
@end defvr

@vindex docdir
@defvr Makefile docdir
The value of this variable names a directory intended to hold any
documentation that is in a format other than @emph{info} or @emph{man}.
The default value for @code{docdir} depends on @code{prefix} so
@code{docdir} is normally changed only indirectly through @code{prefix}.
The default value for @code{docdir} is @code{datadir}@file{/doc}.  Note
that this variable is an extension to the @sc{gnu} coding standards.
(See also @xref{FIXME-now:extensions}.)
@end defvr

@vindex includedir
@defvr Makefile includedir
The value of this variable names a directory intended to hold the
headers files that accompany the libraries installed in @code{libdir}.
The default value for @code{includedir} depends on @code{prefix} so
@code{includedir} is normally changed only indirectly through @code{prefix}.  The default value for
@code{includedir} is @code{prefix}@file{/include}.
@end defvr


@node Build Directories, Host, Install Locations, Using Configure
@section Build Directories

@cindex Build directories
@cindex objdir
@cindex Object directories
@cindex subdirs
@cindex Building for multiple hosts
@cindex Building for multiple targets

Normally, @code{configure} builds @file{Makefile}'s and symbolic links
in the same directory as the source files.  This is the typical
@sc{un*x} way to build programs but it has limitations.  For instance,
using this approach, you can only build for one host at a time.

We refer to the directories in which @code{configure} builds
@file{Makefile}'s as the @emph{build directories} or sometimes as
@emph{objdir} because these are the directories in which @code{make}
will build object files, among other things.

The default build directory is the same as the source directory.

You can change the build directory with a sequence like the following:

@example
mkdir @var{builddir}
cd @var{builddir}
configure @var{host} -srcdir=@var{sourcedirectory}
@example

where @var{builddir} is the directory in which you wish to build,
@var{host} is the host for which you want to build, and
@var{sourcedirectory} is the directory containing the source files.

If you were to do this twice with different values for @var{builddir}
and @vr{host}, then you could @code{make} for both at the same time.

NOTE: The rest of this section describes the @code{-subdirs} feature for
which support is at least temporarily suspended.  FIXME-soon.

Another way to specify the build directory is with the @code{-subdirs}
option.  For example:

@example
configure @var{host} -subdirs
@end example

Using this option, @code{configure} will create a subdirectory named
@file{H-@var{host}} to act as the build directory for each source
directory.

Since building for multiple hosts is so common, @code{configure}
recognizes this situation as special.  For example:

@example
configure @var{host1} @var{host2}
@end example

is precisely the same as:

@example
configure @var{host1} -subdirs
configure @var{host2} -subdirs
#end example

That is, when configuring for multiple hosts or multiple targets,
@code{-subdir} is assumed.

When configuring for cross tools, that is, the host is not the target,
as in:

@example
configure @var{host} +target=@var{targ} -subdirs
@end example

the subdirectories are named @file{X-@var{host}-@var{targ}}.  This is
especially useful when configuring for multiple targets.

If both @code{-subdirs} and @code{-srcdir=} are given, a tree that
parallels the source directory structure is created in the current
directory, except that the current directory represents the source
directory itself, and the subdirectories are created in this directory
tree rather than in the source directories.

NOTE: previously, -subdirs built two level subdirectories as
./H-host/T-target, created ./H-host/Makefile for building across all
targets, ./Makefile for building across all hosts, and ./config.status
and ./H-host/config.status for rebuilding these Makefiles.

@node Host, Target, Build Directories, Using Configure
@section Host

NOTE: support for multiple hosts is at least temporarily suspended.
FIXME-soon.

The arguments to @code{configure} are @emph{hosts}.  By @emph{host} we
mean the environment in which the source will be compiled.  This need
not necessarily be the same as the actual physical machine involved,
although it usually is.

For example, if some obscure machine running an operating system other
than @sc{un*x} actually had the @sc{gnu} @sc{posix} emulation libraries
available, it would be possible to configure most @sc{gnu} source for a
@sc{posix} system and build it on the obscure host.

For more on this topic, see @xref{Host Environments, , cfg-paper, On
Configuring Development Tools}.

@node Target, Local Conventions, Host, Using Configure
@section Target

For building native development tools, or most of the other tools in the
@sc{gnu} collection, you need not worry about the target.  The
@emph{target} of a configuration defaults to the same as the
@emph{host}.

For building cross development tools, please see @xref{Building
Development Environments, , cfg-paper, On Configuring Development
Tools}.

@node Local Conventions,  , Target, Using Configure
@section Local Conventions

If you find that a tool does not get configured to your liking or that
@code{configure}'s conventions are not your local conventions, you
should probably consider site specific Makefile fragments.  (see
@xref{FIXME-now: site specific makefile fragments})

These are probably not the right choice for options that can be set from
the @code{configure} command line or for differences that are host or
target dependent.


@node What Configure Does, Porting, Using Configure, top
@chapter What Configure Does

When configure runs, it does the following things for each source
directory for each host and target combination.

NOTE: support for multiple hosts and targets is at least temporarily
suspended.

@itemize @bullet

@item Create Build Directories
(see @xref{Build Directories}) When @code{configure} is run with the
@code{-srcdir=} option, a directory tree is created that parallels the
directory structure of the source directory except that the current
directory is treated as the build directory for the source directory
proper.  (see @xref{Invoking}).

NOTE: support for @code{-subdirs} is at least temporarily suspended.

When @code{configure} is run with the @code{-subdirs} option, a build
directory is created in each source directory.

If both @code{-subdirs} and @code{-srcdir=} are given, a tree that
parallels the source directory structure is created in the current
directory, except that the current directory represents the source
directory itself, and the subdirectories are created in this directory
tree rather than in the source directories.

@item Generate Makefiles
A makefile template, usually called @file{Makefile.in} from the source
directory is copied to an output file in the build directory.  The
output file is usually named @file{Makefile}.  A number of makefile
macros are prepended to the output file.  If @code{-prefix=} or
@code{-datadir=} were specified on the @code{configure} command line,
then the makefile variables are set accordingly.  If host, target, or
site, specific makefile fragments exist, they are inserted into the
output file.  (see @xref{Makefiles, , , make, Makefiles})

@item Generate .gdbinit
If the source directory contains a .gdbinit file and the build directory
is different from the source directory, a .gdbinit file is created in
the build directory.  (see @xref{Command Files, , , gdb, Command Files})

@item Make Symbolic Links
Most directories have some symbolic links with generic names built
pointing to specific files in the source directory.  If the system on
which @code{configure} is run cannot support symbolic links, then hard
links are used instead.

@item Miscellaneous
If the source directory has special needs, they are handled.  Usually
there are none, but sometimes they involve changes to the output
makefile.

@item Generate config.status
A shell script named @file{config.status} is created in the build
directory.  This shell script, when run from the build directory, will
reconfigure the build directory except that subdirectories are not
reconfigured.  This is most often used by @code{make} to rebuild the
output makefile.  (see @xref{Top, , , bash})

@item Recursion
If the source directory has subdirectories that should also be
configured, then @code{configure} is called for each.

@end itemize

@node Porting, Known Bugs, What Configure Does, top
@chapter Porting with Configure

This section explains briefly how to port configure for:

@menu
* Programs::	Adding configure to existing programs
* Hosts::	Adding new hosts to existing programs
* Targets::	Adding new targets to existing programs
* Reference::	Reference
@end menu

@node Programs,  , Remedies, Adding Hosts Or Targets
@subsection Adding Configure To Existing Programs

If you are writing a new program, don't worry about porting issues or
configure until it is running reasonably on some host.  Then refer
back to this section.

If your 

@c marker

@menu
* Makefile Support::		Makefile Support
* Add Standard Macros (Template Follows)::  Add Standard Macros (Template Follows)
@end menu

@node Makefile Support, Add Standard Macros (Template Follows), Adding Configure To Existing Programs, Adding Configure To Existing Programs
@subsubsection Makefile Support


@menu
* Makefile Host Support - Move It To Host Fragments::  Makefile Host Support - Move It To Host Fragments
@end menu


@node Add Standard Macros (Template Follows),  , Makefile Support, Adding Configure To Existing Programs
@subsubsection Add Standard Macros (Template Follows)

@itemize @bullet
@item as defined in standards.text
@item also add

@itemize @minus
@item includedir
This macro defines the directory in which to install any headers files that should be made available to users.
@item docdir
This macro defines where to install any documentation that is not either a man page or an info file.  For man pages, see mandir,
for info, see infodir.
@end itemize

@item template

@example

# Makefile for GNU tar program.

#
# Makefile
#   Copyright (C) 1990, 1991 Cygnus Support
#
# This file is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
#

srcdir = .

prefix = /usr/local

bindir = $(prefix)/bin
datadir = $(prefix)/lib
libdir = $(prefix)/lib
mandir = $(datadir)/man
man1dir = $(mandir)/man1
man2dir = $(mandir)/man2
man3dir = $(mandir)/man3
man4dir = $(mandir)/man4
man5dir = $(mandir)/man5
man6dir = $(mandir)/man6
man7dir = $(mandir)/man7
man8dir = $(mandir)/man8
man9dir = $(mandir)/man9
infodir = $(datadir)/info
includedir = $(prefix)/include
docdir = $(datadir)/doc

SHELL = /bin/sh

INSTALL = install -c
INSTALL_PROGRAM = $(INSTALL)
INSTALL_DATA = $(INSTALL)

AR = ar
AR_FLAGS = qv
BISON = bison
MAKEINFO = makeinfo
RANLIB = ranlib

# In order to disable remote-tape support, add -DNO_REMOTE to the
# appropriate DEFS line, and remove rtape_lib.* from LOCAL_@{SRC,OBJ@}
# For Ultrix 3.1, you will have to compile rtape_lib.c with -DUSG.
# Add -DUSE_REXEC to use rexec for remote tape operations
# instead of forking rsh or remsh.
#
# If tar fails to properly print error msgs, or core-dumps doing same,
# you may need to change which version of msg...() you are using.
# To do so, add one of the following to your DEFS= line
# -DSTDC_MSG		If you are using an ANSI compiler, and have vfprintf().
# -DVARARGS_MSG		If you have varargs.h and vfprintf()
# -DDOPRNT_MSG		If you have _doprnt(), and no useful varargs support
# -DLOSING_MSG		If nothing else works.
#
# Some non-BSD systems may have to add -DNEED_TZSET in order to have getdate.y
# compile correctly.
#
# If you have a system V system which defines size_t, add -DHAVE_SIZE_T.
# If you have a system which defines strstr, add -DHAVE_STRSTR.
#
# If you can't use remote tar with the rmt library, you can still get
# some stuff to work right by adding -DUSE_REXEC.
#
# Some people's systems define a prototype for signal handlers which
# require them to be declared as void.  If you get such problems in
# rtape_lib, function command, then define -DSIGNAL_VOID.  
#
# getdate.y has 8 shift/reduce conflicts.
#
# In addition to setting DEFS appropriately for your system, you might
# have to hand edit the #defines and #undefs in port.c.
#

## GNU version
DEFS = -DBSD42
LOCAL_SRC = 
LOCAL_OBJ = 
LDFLAGS =
LIBS =  -lutils
LINT = lint
LINTFLAGS = -abchx
DEF_AR_FILE = \"-\"
DEFBLOCKING = 20
O = o
@end example

#### Host, target, and site specific Makefile fragments come in here.
###

@itemize @bullet
@item 		Identify Nonstandard Macros
@itemize @minus
@item 				Put Defaults Before The Fragment Hook (Cf)
@item 				Move Non-Defaults To Makefile Fragments (Cf)
@item 				Map To Those Fragments In Configure.In (Cf)
@end itemize

@item 		Fragment Hook

@itemize @minus
@item 				Should Follow Standard And Non-Standard Macros
@item 				Should Preceed All Targets
@item 				Looks Like
#### Host, target, and site specific Makefile fragments come in here.
###

The line beginning with four hashes is the important part.  The comment and the line beginning with three hashes are only
a conventional convenience.
@end itemize

@item 		Makefile Fragments
@item 				Host
@item 				Target
@item 				Site
@item Mv Makefile Makefile.In
@item 		Standard Targets
@item 				All (Should Be The Default)
@item 				Install
@item 				Clean
@item 				Info
@item 				Install-Info
@item 				Clean-Info
@item The Config Subdirectory
@item Configure.In
@item 		Declarations
@item 				Srctrigger
@item 				Srcname
@item 				Configdirs
@item 				Target_Dependent
@item 		Per-Host
@item 		Per-Target
@item 		Post-Target
@item 		Available Variables

@defvar{host}
Contains the actual name that the user entered for the host.  Since many
things that the user could enter would map to the same canonical triple,
this variable is innappropriate to use for picking available
configurations.  For that, use @code{host_cpu}, @code{host_vendor},
and/or @code{host_os}.  This variable is useful, however, for error
messages.
@end defvar

@defvar{host_cpu}
Contains the first element of the canonical triple representing the host
as returned by @file{config.subr}.  This is occasionally used to
distinguish between minor variations of a particular vendor's operating
system and sometimes to determine variations in binary format between
the host and the target.
@end defvar

@defvar{host_vendor}
Contains the second element of the canonical triple representing the
host as returned by @file{config.subr}.  This is usually used to
distinguish betwen the numerous variations between @emph{common}
operating systems.
@end defvar

@defvar{host_os}
Contains the the third element of the canonical triple representing the
host as returned by @file{config.subr}.
@end defvar

@defvar{target}
Contains the actual name that the user entered for the target.  Since many
things that the user could enter would map to the same canonical triple,
this variable is innappropriate to use for picking available
configurations.  For that, use @code{target_cpu}, @code{target_vendor},
and/or @code{target_os}.  This variable is useful, however, for error
messages.
@end defvar

@defvar{target_cpu}
Contains the first element of the canonical triple representing the
target as returned by @file{config.subr}.  This is used heavily by
programs involved in building programs, like the compiler, assembler,
linker, etc.  Most programs will not need the @code{target} variables at
all, but this one could conceivably be used to build a program, for
instance, that operated on binary data files whose byte order or
alignment are other than that of the system on which the program is
running.
@end defvar

@defvar{target_vendor}
Contains the second element of the canonical triple representing the
target as returned by @file{config.subr}.  This is usually used to
distinguish betwen the numerous variations between @emph{common}
operating systems or object file formats.  Sometimes it is used to
switch between different flavors of users interfaces.
@end defvar

@defvar{target_os}
Contains the the third element of the canonical triple representing the
target as returned by @file{config.subr}.  This variable is used by
development tools to distinguish between subtle variations in object
file formats that some vendors use across operating system releases.  It
might also be use to decide which libraries to build or what user
interface the tool should provide.
@end defvar

@defvar{nfp}
Is set to @code{true} if the user invoked configure with the @code{-nfp}
command line option, otherwise it is empty.  This is a request to target
a machine with @emph{no floating point} unit, even if the machine ordinarily
has a floating point unit available.  This option has no negation.
@end defvar

@defvar{gas}
Is set to @code{true} if the user invoked configure with the @code{-gas}
command line option, otherwise it is empty.  This is a request to assume
that the target machine has gas available even if it ordinarily does
not.  The converse option, @code{-no-gas} is not available.
@end defvar

@defvar{x}
Is set to @code{true} if the user invoked configure with the @code{-x}
command line option, otherwise it is empty.  This is a request to assume
that @sc{mit x11} compatible headers files and libraries are available,
regardless of what is normally available on this host.
@end defvar

@defvar{srcdir}
Is set to the name of the directory containing the source for this
program.  This will be different from @file{.} if the user has
specified either the @code{-srcdir=} or the @code{-subdirs} options.
Note that @code{srcdir} is not necessarily an absolute path.
@end defvar

@defvar{host_makefile_frag}
Is set to a file name representing to the default Makefile fragment for
this host.  It may be set in @file{configure.in} to overide this
default.
@end defvar

@defvar{target_makefile_frag}
Is set to a file name representing to the default Makefile fragment for
this target.  It may be set in @file{configure.in} to overide this
default.
@end defvar

@defvar{site_makefile_frag}
Is set to a file name representing to the default Makefile fragment for
this host.  It may be set in @file{configure.in} to overide this
default.  Normally @code{site_makefile_frag} is empty, but will have a
value if the user specified @code{-site=} on the command line.  This
variable should probably not be overridden.
@end defvar

@defvar{Makefile}
Is set to the name of the generated @file{Makefile}.  Normally this
value is precisely @file{Makefile} but some programs may want something
else.
@end defvar

@defvar{removing}
Is normally empty but will be set to some non-empty value if the user
specified @code{-rm} on the command line.  That is, if @code{removing}
is non-empty, then configure is @emph{removing} a configuration rather
than creating one.
@end defvar

@defvar{files}
If this variable is non-empty following the @code{per-target:} section,
then each word in it's value will be the target of a symbolic link
named in the @code{links} variable.
@end defvar

@defvar{links}
If the @code{files} variable is non-empty following the
@code{per-target:} section, then symbolic links will be created with the
first word of links pointing to the first word of files, the second word of
links pointing to the second word of files, and so on.
@end defvar

@end itemize
@end itemize

@node Native Ports, Adding Hosts Or Targets, Porting, Porting
@section Native Ports

To port a GNU tool that uses the Cygnus Configure system, do the
following.

@itemize @asis

@item Add A Host
@item Port An Existing Target
@item Add A Target
@item Build Host & Target
@item Build New Target On Some Other Host

@end table

@node Adding Hosts Or Targets, Reference, Native Ports, Porting
@section Adding Hosts Or Targets



@menu
* Add Canonical Triple To Config.Subr (Cf Config.Subr)::  Add Canonical Triple To Config.Subr (Cf Config.Subr)
* (Optional) Add Alias (Cf Config.Subr)::  
* Monte Carlo - Configure ; Make::  Monte Carlo - Configure ; Make
* Remedies::			Remedies
* Adding Configure To Existing Programs::  Adding Configure To Existing Programs
@end menu

@node Add Canonical Triple To Config.Subr (Cf Config.Subr), (Optional) Add Alias (Cf Config.Subr), Adding Hosts Or Targets, Adding Hosts Or Targets
@subsection Add Canonical Triple To Config.Subr (Cf Config.Subr)


@node (Optional) Add Alias (Cf Config.Subr), Monte Carlo - Configure ; Make, Add Canonical Triple To Config.Subr (Cf Config.Subr), Adding Hosts Or Targets
@subsection (Optional) Add Alias (Cf Config.Subr)


@node Monte Carlo - Configure ; Make, Remedies, (Optional) Add Alias (Cf Config.Subr), Adding Hosts Or Targets
@subsection Monte Carlo - Configure ; Make


@node Remedies, Adding Configure To Existing Programs, Monte Carlo - Configure ; Make, Adding Hosts Or Targets
@subsection Remedies


@menu
* Automagic Config::		Automagic Config
* Symlinked Files::		Symlinked Files
* Makefile Fragments (Cf Configure.In)::  Makefile Fragments (Cf Configure.In)
@end menu

@node Automagic Config, Symlinked Files, Remedies, Remedies
@subsubsection Automagic Config


@node Symlinked Files, Makefile Fragments (Cf Configure.In), Automagic Config, Remedies
@subsubsection Symlinked Files


@node Makefile Fragments (Cf Configure.In),  , Symlinked Files, Remedies
@subsubsection Makefile Fragments (Cf Configure.In)

@node Reference,  , Adding Hosts Or Targets, Porting
@section Reference



Automagic Configuration Should Be Used If Prep'D Files Don'T Exist.

@node Known Bugs, Variables Index, Porting, top
@chapter Known Bugs

The following bugs are known to exist.

@itemize @bullet

@item
There is no way to query about known hosts, known targets, or the
porting or testing status of any configuration.

@item
The negations to the options @code{-gas}, @code{-x}, and @code{-nfp} are
not available.

@end itemize

@node Variables Index, Concept Index, Known Bugs, top
@appendix Variable Index

@printindex vr

@node     Concept Index,  , Variables Index, top
@appendix Concept Index

@printindex cp
@contents
@bye

@c Local Variables:
@c fill-column: 79
@c outline-regexp: "@chap"
@c End:
@c (setq outline-regexp "@chapt\\\|@unnum\\\|@setf\\\|@conte\\\|@sectio\\\|@subsect\\\|@itemize\\\|@defvar{")