Installation Instructions
 *************************
 

    Copyright (C) 1994-1996, 1999-2002, 2004-2016 Free Software
 Foundation, Inc.

 
    Copying and distribution of this file, with or without modification,
 are permitted in any medium without royalty provided the copyright
 notice and this notice are preserved.  This file is offered as-is,
 without warranty of any kind.
 
 Basic Installation
 ==================
 

    Briefly, the shell command './configure && make && make install'

 should configure, build, and install this package.  The following

 more-detailed instructions are generic; see the 'README' file for

 instructions specific to this package.  Some packages provide this

 'INSTALL' file but do not implement all of the features documented

 below.  The lack of an optional feature in a given package is not
 necessarily a bug.  More recommendations for GNU packages can be found
 in *note Makefile Conventions: (standards)Makefile Conventions.
 

    The 'configure' shell script attempts to guess correct values for

 various system-dependent variables used during compilation.  It uses

 those values to create a 'Makefile' in each directory of the package.
 It may also create one or more '.h' files containing system-dependent
 definitions.  Finally, it creates a shell script 'config.status' that

 you can run in the future to recreate the current configuration, and a

 file 'config.log' containing compiler output (useful mainly for
 debugging 'configure').

    It can also use an optional file (typically called 'config.cache' and
 enabled with '--cache-file=config.cache' or simply '-C') that saves the
 results of its tests to speed up reconfiguring.  Caching is disabled by
 default to prevent problems with accidental use of stale cache files.

 
    If you need to do unusual things to compile the package, please try

 to figure out how 'configure' could check whether to do them, and mail
 diffs or instructions to the address given in the 'README' so they can

 be considered for the next release.  If you are using the cache, and at

 some point 'config.cache' contains results you don't want to keep, you

 may remove or edit it.
 

    The file 'configure.ac' (or 'configure.in') is used to create
 'configure' by a program called 'autoconf'.  You need 'configure.ac' if
 you want to change it or regenerate 'configure' using a newer version of
 'autoconf'.

 
    The simplest way to compile this package is:
 

   1. 'cd' to the directory containing the package's source code and type
      './configure' to configure the package for your system.

      Running 'configure' might take a while.  While running, it prints

      some messages telling which features it is checking for.
 

   2. Type 'make' to compile the package.

   3. Optionally, type 'make check' to run any self-tests that come with

      the package, generally using the just-built uninstalled binaries.
 

   4. Type 'make install' to install the programs and any data files and

      documentation.  When installing into a prefix owned by root, it is
      recommended that the package be configured and built as a regular

      user, and only the 'make install' phase executed with root

      privileges.
 

   5. Optionally, type 'make installcheck' to repeat any self-tests, but

      this time using the binaries in their final installed location.
      This target does not install anything.  Running this target as a

      regular user, particularly if the prior 'make install' required

      root privileges, verifies that the installation completed
      correctly.
 
   6. You can remove the program binaries and object files from the

      source code directory by typing 'make clean'.  To also remove the
      files that 'configure' created (so you can compile the package for
      a different kind of computer), type 'make distclean'.  There is
      also a 'make maintainer-clean' target, but that is intended mainly

      for the package's developers.  If you use it, you may have to get
      all sorts of other programs in order to regenerate files that came
      with the distribution.
 

   7. Often, you can also type 'make uninstall' to remove the installed

      files again.  In practice, not all packages have tested that
      uninstallation works correctly, even though it is required by the
      GNU Coding Standards.
 

   8. Some packages, particularly those that use Automake, provide 'make

      distcheck', which can by used by developers to test that all other

      targets like 'make install' and 'make uninstall' work correctly.

      This target is generally not run by end users.
 
 Compilers and Options
 =====================
 
    Some systems require unusual options for compilation or linking that

 the 'configure' script does not know about.  Run './configure --help'

 for details on some of the pertinent environment variables.
 

    You can give 'configure' initial values for configuration parameters
 by setting variables in the command line or in the environment.  Here is
 an example:

 
      ./configure CC=c99 CFLAGS=-g LIBS=-lposix
 
    *Note Defining Variables::, for more details.
 
 Compiling For Multiple Architectures
 ====================================
 
    You can compile the package for more than one kind of computer at the
 same time, by placing the object files for each architecture in their

 own directory.  To do this, you can use GNU 'make'.  'cd' to the

 directory where you want the object files and executables to go and run

 the 'configure' script.  'configure' automatically checks for the source
 code in the directory that 'configure' is in and in '..'.  This is known
 as a "VPATH" build.

    With a non-GNU 'make', it is safer to compile the package for one

 architecture at a time in the source code directory.  After you have

 installed the package for one architecture, use 'make distclean' before

 reconfiguring for another architecture.
 
    On MacOS X 10.5 and later systems, you can create libraries and
 executables that work on multiple system types--known as "fat" or

 "universal" binaries--by specifying multiple '-arch' options to the
 compiler but only a single '-arch' option to the preprocessor.  Like

 this:
 
      ./configure CC="gcc -arch i386 -arch x86_64 -arch ppc -arch ppc64" \
                  CXX="g++ -arch i386 -arch x86_64 -arch ppc -arch ppc64" \
                  CPP="gcc -E" CXXCPP="g++ -E"
 
    This is not guaranteed to produce working output in all cases, you
 may have to build one architecture at a time and combine the results

 using the 'lipo' tool if you have problems.

 
 Installation Names
 ==================
 

    By default, 'make install' installs the package's commands under
 '/usr/local/bin', include files under '/usr/local/include', etc.  You
 can specify an installation prefix other than '/usr/local' by giving
 'configure' the option '--prefix=PREFIX', where PREFIX must be an

 absolute file name.
 
    You can specify separate installation prefixes for
 architecture-specific files and architecture-independent files.  If you

 pass the option '--exec-prefix=PREFIX' to 'configure', the package uses

 PREFIX as the prefix for installing programs and libraries.
 Documentation and other data files still use the regular prefix.
 
    In addition, if you use an unusual directory layout you can give

 options like '--bindir=DIR' to specify different values for particular
 kinds of files.  Run 'configure --help' for a list of the directories
 you can set and what kinds of files go in them.  In general, the default
 for these options is expressed in terms of '${prefix}', so that
 specifying just '--prefix' will affect all of the other directory

 specifications that were not explicitly provided.
 
    The most portable way to affect installation locations is to pass the

 correct locations to 'configure'; however, many packages provide one or

 both of the following shortcuts of passing variable assignments to the

 'make install' command line to change installation locations without

 having to reconfigure or recompile.
 
    The first method involves providing an override variable for each

 affected directory.  For example, 'make install

 prefix=/alternate/directory' will choose an alternate location for all
 directory configuration variables that were expressed in terms of

 '${prefix}'.  Any directories that were specified during 'configure',
 but not in terms of '${prefix}', must each be overridden at install time
 for the entire installation to be relocated.  The approach of makefile
 variable overrides for each directory variable is required by the GNU
 Coding Standards, and ideally causes no recompilation.  However, some
 platforms have known limitations with the semantics of shared libraries
 that end up requiring recompilation when using this method, particularly
 noticeable in packages that use GNU Libtool.
 
    The second method involves providing the 'DESTDIR' variable.  For
 example, 'make install DESTDIR=/alternate/directory' will prepend
 '/alternate/directory' before all installation names.  The approach of
 'DESTDIR' overrides is not required by the GNU Coding Standards, and

 does not work on platforms that have drive letters.  On the other hand,
 it does better at avoiding recompilation issues, and works well even

 when some directory options were not specified in terms of '${prefix}'
 at 'configure' time.

 
 Optional Features
 =================
 
    If the package supports it, you can cause programs to be installed

 with an extra prefix or suffix on their names by giving 'configure' the
 option '--program-prefix=PREFIX' or '--program-suffix=SUFFIX'.
 
    Some packages pay attention to '--enable-FEATURE' options to
 'configure', where FEATURE indicates an optional part of the package.
 They may also pay attention to '--with-PACKAGE' options, where PACKAGE
 is something like 'gnu-as' or 'x' (for the X Window System).  The
 'README' should mention any '--enable-' and '--with-' options that the

 package recognizes.
 

    For packages that use the X Window System, 'configure' can usually

 find the X include and library files automatically, but if it doesn't,

 you can use the 'configure' options '--x-includes=DIR' and
 '--x-libraries=DIR' to specify their locations.

 
    Some packages offer the ability to configure how verbose the

 execution of 'make' will be.  For these packages, running './configure

 --enable-silent-rules' sets the default to minimal output, which can be

 overridden with 'make V=1'; while running './configure

 --disable-silent-rules' sets the default to verbose, which can be

 overridden with 'make V=0'.

 
 Particular systems
 ==================
 

    On HP-UX, the default C compiler is not ANSI C compatible.  If GNU CC
 is not installed, it is recommended to use the following options in

 order to use an ANSI C compiler:
 
      ./configure CC="cc -Ae -D_XOPEN_SOURCE=500"
 
 and if that doesn't work, install pre-built binaries of GCC for HP-UX.
 

    HP-UX 'make' updates targets which have the same time stamps as their
 prerequisites, which makes it generally unusable when shipped generated
 files such as 'configure' are involved.  Use GNU 'make' instead.

 
    On OSF/1 a.k.a. Tru64, some versions of the default C compiler cannot

 parse its '<wchar.h>' header file.  The option '-nodtk' can be used as a
 workaround.  If GNU CC is not installed, it is therefore recommended to
 try

 
      ./configure CC="cc"
 
 and if that doesn't work, try
 
      ./configure CC="cc -nodtk"
 

    On Solaris, don't put '/usr/ucb' early in your 'PATH'.  This

 directory contains several dysfunctional programs; working variants of

 these programs are available in '/usr/bin'.  So, if you need '/usr/ucb'
 in your 'PATH', put it _after_ '/usr/bin'.

    On Haiku, software installed for all users goes in '/boot/common',
 not '/usr/local'.  It is recommended to use the following options:

 
      ./configure --prefix=/boot/common
 
 Specifying the System Type
 ==========================
 

    There may be some features 'configure' cannot figure out

 automatically, but needs to determine by the type of machine the package
 will run on.  Usually, assuming the package is built to be run on the

 _same_ architectures, 'configure' can figure that out, but if it prints

 a message saying it cannot guess the machine type, give it the

 '--build=TYPE' option.  TYPE can either be a short name for the system
 type, such as 'sun4', or a canonical name which has the form:

 
      CPU-COMPANY-SYSTEM
 
 where SYSTEM can have one of these forms:
 
      OS
      KERNEL-OS
 

    See the file 'config.sub' for the possible values of each field.  If
 'config.sub' isn't included in this package, then this package doesn't

 need to know the machine type.
 
    If you are _building_ compiler tools for cross-compiling, you should

 use the option '--target=TYPE' to select the type of system they will

 produce code for.
 
    If you want to _use_ a cross compiler, that generates code for a
 platform different from the build platform, you should specify the
 "host" platform (i.e., that on which the generated programs will

 eventually be run) with '--host=TYPE'.

 
 Sharing Defaults
 ================
 

    If you want to set default values for 'configure' scripts to share,
 you can create a site shell script called 'config.site' that gives
 default values for variables like 'CC', 'cache_file', and 'prefix'.
 'configure' looks for 'PREFIX/share/config.site' if it exists, then
 'PREFIX/etc/config.site' if it exists.  Or, you can set the
 'CONFIG_SITE' environment variable to the location of the site script.
 A warning: not all 'configure' scripts look for a site script.

 
 Defining Variables
 ==================
 
    Variables not defined in a site shell script can be set in the

 environment passed to 'configure'.  However, some packages may run

 configure again during the build, and the customized values of these
 variables may be lost.  In order to avoid this problem, you should set

 them in the 'configure' command line, using 'VAR=value'.  For example:

 
      ./configure CC=/usr/local2/bin/gcc
 

 causes the specified 'gcc' to be used as the C compiler (unless it is

 overridden in the site shell script).
 

 Unfortunately, this technique does not work for 'CONFIG_SHELL' due to an
 Autoconf limitation.  Until the limitation is lifted, you can use this
 workaround:

 
      CONFIG_SHELL=/bin/bash ./configure CONFIG_SHELL=/bin/bash
 

 'configure' Invocation

 ======================
 

    'configure' recognizes the following options to control how it

 operates.
 

 '--help'
 '-h'
      Print a summary of all of the options to 'configure', and exit.

 '--help=short'
 '--help=recursive'

      Print a summary of the options unique to this package's

      'configure', and exit.  The 'short' variant lists options used only
      in the top level, while the 'recursive' variant lists options also
      present in any nested packages.

 '--version'
 '-V'
      Print the version of Autoconf used to generate the 'configure'

      script, and exit.
 

 '--cache-file=FILE'

      Enable the cache: use and save the results of the tests in FILE,

      traditionally 'config.cache'.  FILE defaults to '/dev/null' to

      disable caching.
 

 '--config-cache'
 '-C'
      Alias for '--cache-file=config.cache'.

 '--quiet'
 '--silent'
 '-q'

      Do not print messages saying which checks are being made.  To

      suppress all normal output, redirect it to '/dev/null' (any error

      messages will still be shown).
 

 '--srcdir=DIR'

      Look for the package's source code in directory DIR.  Usually

      'configure' can determine that directory automatically.

 '--prefix=DIR'
      Use DIR as the installation prefix.  *note Installation Names:: for
      more details, including other options available for fine-tuning the
      installation locations.

 '--no-create'
 '-n'

      Run the configure checks, but stop before creating any output
      files.
 

 'configure' also accepts some other, not widely useful, options.  Run
 'configure --help' for more details.