path: root/INSTALL

** This file is adapted from libcurl and not yet fully rewritten for c-ares! **

                          ___       __ _ _ __ ___  ___ 
                         / __| ___ / _` | '__/ _ \/ __|
                        | (_  |___| (_| | | |  __/\__ \
                         \___|     \__,_|_|  \___||___/

                                How To Compile

Installing Binary Packages
==========================

   Lots of people download binary distributions of c-ares. This document
   does not describe how to install c-ares using such a binary package.
   This document describes how to compile, build and install c-ares from
   source code.

Building from git
=================

   If you get your code off a git repository, see the GIT-INFO file in the
   root directory for specific instructions on how to proceed.

UNIX
====
   A normal unix installation is made in three or four steps (after you've
   unpacked the source archive):

        ./configure
        make
        make test (optional)
        make install

   You probably need to be root when doing the last command.

   If you have checked out the sources from the git repository, read the
   GIT-INFO on how to proceed.

   Get a full listing of all available configure options by invoking it like:

        ./configure --help

   If you want to install c-ares in a different file hierarchy than /usr/local,
   you need to specify that already when running configure:

        ./configure --prefix=/path/to/c-ares/tree

   If you happen to have write permission in that directory, you can do 'make
   install' without being root. An example of this would be to make a local
   install in your own home directory:

        ./configure --prefix=$HOME
        make
        make install

   MORE OPTIONS
   ------------

     To force configure to use the standard cc compiler if both cc and gcc are
     present, run configure like

       CC=cc ./configure
         or
       env CC=cc ./configure

     To force a static library compile, disable the shared library creation
     by running configure like:

       ./configure --disable-shared

     To tell the configure script to skip searching for thread-safe functions,
     add an option like:

       ./configure --disable-thread

     If you're a c-ares developer and use gcc, you might want to enable more
     debug options with the --enable-debug option.

   SPECIAL CASES
   -------------
   Some versions of uClibc require configuring with CPPFLAGS=-D_GNU_SOURCE=1
   to get correct large file support.

   The Open Watcom C compiler on Linux requires configuring with the variables:

       ./configure CC=owcc AR="$WATCOM/binl/wlib" AR_FLAGS=-q \
           RANLIB=/bin/true STRIP="$WATCOM/binl/wstrip" CFLAGS=-Wextra


Win32
=====

   Building Windows DLLs and C run-time (CRT) linkage issues
   ---------------------------------------------------------

   As a general rule, building a DLL with static CRT linkage is highly
   discouraged, and intermixing CRTs in the same app is something to
   avoid at any cost.

   Reading and comprehension of Microsoft Knowledge Base articles
   KB94248 and KB140584 is a must for any Windows developer. Especially
   important is full understanding if you are not going to follow the
   advice given above.

   KB94248  - How To Use the C Run-Time
              http://support.microsoft.com/kb/94248/en-us

   KB140584 - How to link with the correct C Run-Time (CRT) library
              http://support.microsoft.com/kb/140584/en-us

   KB190799 - Potential Errors Passing CRT Objects Across DLL Boundaries
              http://msdn.microsoft.com/en-us/library/ms235460

   If your app is misbehaving in some strange way, or it is suffering
   from memory corruption, before asking for further help, please try
   first to rebuild every single library your app uses as well as your
   app using the debug multithreaded dynamic C runtime.

   MingW32
   -------

   Make sure that MinGW32's bin dir is in the search path, for example:

     set PATH=c:\mingw32\bin;%PATH%

   then run 'mingw32-make' in the root dir.
   There is another make target available to build the demo files:
   'mingw32-make demos'

   Cygwin
   ------

   Almost identical to the unix installation. Run the configure script in the
   c-ares root with 'sh configure'. Make sure you have the sh executable in
   /bin/ or you'll see the configure fail toward the end.

   Run 'make'

   Dev-Cpp
   -------

   See the separate INSTALL.devcpp file for details.

   MSVC 6 caveats
   --------------

   If you use MSVC 6 it is required that you use the February 2003 edition PSDK:
   http://www.microsoft.com/msdownload/platformsdk/sdkupdate/psdk-full.htm

   Building any software with MSVC 6 without having PSDK installed is just
   asking for trouble down the road once you have released it, you might notice
   the problems in the first corner or ten miles ahead, depending mostly on your
   choice of static vs dynamic runtime and third party libraries. Anyone using
   software built in such way will at some point regret having done so.

   When someone uses MSVC 6 without PSDK he is using a compiler back from 1998.

   If the compiler has been updated with the installation of a service pack as
   those mentioned in http://support.microsoft.com/kb/194022 the compiler can be
   safely used to read source code, translate and make it object code.

   But, even with the service packs mentioned above installed, the resulting
   software generated in such an environment will be using outdated system
   header files and libraries with bugs and security issues which have already
   been addressed and fixed long time ago.

   In order to make use of the updated system headers and fixed libraries
   for MSVC 6, it is required that 'Platform SDK', PSDK from now onwards,
   is installed. The specific PSDK that must be installed for MSVC 6 is the
   February 2003 edition, which is the latest one supporting the MSVC 6 compiler,
   this PSDK is also known as 'Windows Server 2003 PSDK' and can be downloaded
   from http://www.microsoft.com/msdownload/platformsdk/sdkupdate/psdk-full.htm

   So, building c-ares and libc-ares with MSVC 6 without PSDK is absolutely
   discouraged for the benefit of anyone using software built in such
   environment. And it will not be supported in any way, as we could just
   be hunting bugs which have already been fixed way back in 2003.

   When building with MSVC 6 we attempt to detect if PSDK is not being used,
   and if this is the case the build process will fail hard with an error
   message stating that the February 2003 PSDK is required. This is done to
   protect the unsuspecting and avoid PEBKAC issues.

   Additionally it might happen that a die hard MSVC hacker still wants to
   build c-ares and libc-ares with MSVC 6 without PSDK installed, even knowing
   that this is a highly discouraged and unsupported build environment. In
   this case the brave of heart will be able to build in such an environment
   with the requisite of defining preprocessor symbol ALLOW_MSVC6_WITHOUT_PSDK
   in lib/config-win32.h and knowing that LDAP and IPv6 support will be missing.

   MSVC from command line
   ----------------------

   Run the 'vcvars32.bat' file to get a proper environment. The
   vcvars32.bat file is part of the Microsoft development environment and
   you may find it in 'C:\Program Files\Microsoft Visual Studio\vc98\bin'
   provided that you installed Visual C/C++ 6 in the default directory.

   Then run 'nmake vc' in c-ares's root directory.

   If you want to compile with zlib support, you will need to build
   zlib (http://www.gzip.org/zlib/) as well. Please read the zlib
   documentation on how to compile zlib. Define the ZLIB_PATH environment
   variable to the location of zlib.h and zlib.lib, for example:

     set ZLIB_PATH=c:\zlib-1.2.6

   Then run 'nmake vc-zlib' in c-ares's root directory.

   If you want to compile with SSL support you need the OpenSSL package.
   Please read the OpenSSL documentation on how to compile and install
   the OpenSSL libraries.  The build process of OpenSSL generates the
   libeay32.dll and ssleay32.dll files in the out32dll subdirectory in
   the OpenSSL home directory.  OpenSSL static libraries (libeay32.lib,
   ssleay32.lib, RSAglue.lib) are created in the out32 subdirectory.

   Before running nmake define the OPENSSL_PATH environment variable with
   the root/base directory of OpenSSL, for example:

     set OPENSSL_PATH=c:\openssl-0.9.8u

   Then run 'nmake vc-ssl' or 'nmake vc-ssl-dll' in c-ares's root
   directory.  'nmake vc-ssl' will create a libc-ares static and dynamic
   libraries in the lib subdirectory, as well as a statically linked
   version of c-ares.exe in the src subdirectory.  This statically linked
   version is a standalone executable not requiring any DLL at
   runtime. This make method requires that you have the static OpenSSL
   libraries available in OpenSSL's out32 subdirectory.
   'nmake vc-ssl-dll' creates the libc-ares dynamic library and
   links c-ares.exe against libc-ares and OpenSSL dynamically.
   This executable requires libc-ares.dll and the OpenSSL DLLs
   at runtime.
   Run 'nmake vc-ssl-zlib' to build with both ssl and zlib support.

   MSVC 6 IDE
   ----------

   A minimal VC++ 6.0 reference workspace (vc6c-ares.dsw) is available with the
   source distribution archive to allow proper building of the two included
   projects, the libc-ares library and the c-ares tool.

   1) Open the vc6c-ares.dsw workspace with MSVC6's IDE.
   2) Select 'Build' from top menu.
   3) Select 'Batch Build' from dropdown menu.
   4) Make sure that the eight project configurations are 'checked'.
   5) Click on the 'Build' button.
   6) Once the eight project configurations are built you are done.

   Dynamic and static libc-ares libraries are built in debug and release flavours,
   and can be located each one in its own subdirectory, DLL-Debug, DLL-Release,
   LIB-Debug and LIB-Release, all of them below the 'lib' subdirectory.

   In the same way four c-ares executables are created, each using its respective
   library. The resulting c-ares executables are located in its own subdirectory,
   DLL-Debug, DLL-Release, LIB-Debug and LIB-Release, below the 'src' subdir.

   These reference VC++ 6.0 configurations are generated using the dynamic CRT.

   Intentionally, these reference VC++ 6.0 projects and configurations don't use
   third party libraries, such as OpenSSL or Zlib, to allow proper compilation
   and configuration for all new users without further requirements.

   If you need something more 'involved' you might adjust them for your own use,
   or explore the world of makefiles described above 'MSVC from command line'.

   Borland C++ compiler
   ---------------------

   Ensure that your build environment is properly set up to use the compiler
   and associated tools. PATH environment variable must include the path to
   bin subdirectory of your compiler installation, eg: c:\Borland\BCC55\bin

   It is advisable to set environment variable BCCDIR to the base path of
   the compiler installation.

     set BCCDIR=c:\Borland\BCC55

   In order to build a plain vanilla version of c-ares and libc-ares run the
   following command from c-ares's root directory:

     make borland

   To build c-ares and libc-ares with zlib and OpenSSL support set environment
   variables ZLIB_PATH and OPENSSL_PATH to the base subdirectories of the
   already built zlib and OpenSSL libraries and from c-ares's root directory
   run command:

     make borland-ssl-zlib

   libc-ares library will be built in 'lib' subdirectory while c-ares tool
   is built in 'src' subdirectory. In order to use libc-ares library it is
   advisable to modify compiler's configuration file bcc32.cfg located
   in c:\Borland\BCC55\bin to reflect the location of libraries include
   paths for example the '-I' line could result in something like:

     -I"c:\Borland\BCC55\include;c:\c-ares\include;c:\openssl\inc32"

   bcc3.cfg '-L' line could also be modified to reflect the location of
   of libc-ares library resulting for example:

     -L"c:\Borland\BCC55\lib;c:\c-ares\lib;c:\openssl\out32"

   In order to build sample program 'simple.c' from the docs\examples
   subdirectory run following command from mentioned subdirectory:

     bcc32 simple.c libc-ares.lib cw32mt.lib

   In order to build sample program simplessl.c an SSL enabled libc-ares
   is required, as well as the OpenSSL libeay32.lib and ssleay32.lib
   libraries.


   OTHER MSVC IDEs
   ---------------

   If you use VC++, Borland or similar compilers. Include all lib source
   files in a static lib "project" (all .c and .h files that is).
   (you should name it libc-ares or similar)

   Make the sources in the src/ drawer be a "win32 console application"
   project. Name it c-ares.


   Important static c-ares usage note
   ----------------------------------

   When building an application that uses the static libc-ares library, you must
   add '-DCURL_STATICLIB' to your CFLAGS.  Otherwise the linker will look for
   dynamic import symbols.


IBM OS/2
========
   Building under OS/2 is not much different from building under unix.
   You need:

      - emx 0.9d
      - GNU make
      - GNU patch
      - ksh
      - GNU bison
      - GNU file utilities
      - GNU sed
      - autoconf 2.13

   If you want to build with OpenSSL or OpenLDAP support, you'll need to
   download those libraries, too. Dirk Ohme has done some work to port SSL
   libraries under OS/2, but it looks like he doesn't care about emx.  You'll
   find his patches on: http://come.to/Dirk_Ohme

   If during the linking you get an error about _errno being an undefined
   symbol referenced from the text segment, you need to add -D__ST_MT_ERRNO__
   in your definitions.

   If everything seems to work fine but there's no c-ares.exe, you need to add
   -Zexe to your linker flags.

   If you're getting huge binaries, probably your makefiles have the -g in
   CFLAGS.


VMS
===
   (The VMS section is in whole contributed by the friendly Nico Baggus)

   Curl seems to work with FTP & HTTP other protocols are not tested.  (the
   perl http/ftp testing server supplied as testing too cannot work on VMS
   because vms has no concept of fork(). [ I tried to give it a whack, but
   thats of no use.

   SSL stuff has not been ported.

   Telnet has about the same issues as for Win32. When the changes for Win32
   are clear maybe they'll work for VMS too. The basic problem is that select
   ONLY works for sockets.

   Marked instances of fopen/[f]stat that might become a problem, especially
   for non stream files. In this regard, the files opened for writing will be
   created stream/lf and will thus be safe. Just keep in mind that non-binary
   read/wring from/to files will have a records size limit of 32767 bytes
   imposed.

   Stat to get the size of the files is again only safe for stream files &
   fixed record files without implied CC.

   -- My guess is that only allowing access to stream files is the quickest
   way to get around the most issues. Therefore all files need to to be
   checked to be sure they will be stream/lf before processing them.  This is
   the easiest way out, I know. The reason for this is that code that needs to
   report the filesize will become a pain in the ass otherwise.

   Exit status.... Well we needed something done here,

   VMS has a structured exist status:
   | 3  |       2    |     1       |  0|
   |1098|765432109876|5432109876543|210|
   +----+------------+-------------+---+
   |Ctrl|  Facility  | Error code  |sev|
   +----+------------+-------------+---+

   With the Ctrl-bits an application can tell if part or the whole message has
   already been printed from the program, DCL doesn't need to print it again.

   Facility - basically the program ID. A code assigned to the program
   the name can be fetched from external or internal message libraries
   Error code - the err codes assigned by the application
   Sev. - severity: Even = error, off = non error
      0 = Warning
      1 = Success
      2 = Error
      3 = Information
      4 = Fatal
      <5-7> reserved.

   This all presents itself with:
   %<FACILITY>-<Sev>-<Errorname>, <Error message>

   See also the src/c-aresmsg.msg file, it has the source for the messages In
   src/main.c a section is devoted to message status values, the globalvalues
   create symbols with certain values, referenced from a compiled message
   file. Have all exit function use a exit status derived from a translation
   table with the compiled message codes.

   This was all compiled with:

      Compaq C V6.2-003 on OpenVMS Alpha V7.1-1H2

   So far for porting notes as of:
   13-jul-2001
   N. Baggus


QNX
===
   (This section was graciously brought to us by David Bentham)

   As QNX is targeted for resource constrained environments, the QNX headers
   set conservative limits. This includes the FD_SETSIZE macro, set by default
   to 32. Socket descriptors returned within the CURL library may exceed this,
   resulting in memory faults/SIGSEGV crashes when passed into select(..)
   calls using fd_set macros.

   A good all-round solution to this is to override the default when building
   libc-ares, by overriding CFLAGS during configure, example
   #  configure CFLAGS='-DFD_SETSIZE=64 -g -O2'


RISC OS
=======
   The library can be cross-compiled using gccsdk as follows:

        CC=riscos-gcc AR=riscos-ar RANLIB='riscos-ar -s' ./configure \
             --host=arm-riscos-aof --without-random --disable-shared
        make

   where riscos-gcc and riscos-ar are links to the gccsdk tools.
   You can then link your program with c-ares/lib/.libs/libc-ares.a


AmigaOS
=======
   (This section was graciously brought to us by Diego Casorran)

   To build cURL/libc-ares on AmigaOS just type 'make amiga' ...

   What you need is:    (not tested with others versions)

        GeekGadgets / gcc 2.95.3 (http://www.geekgadgets.org/)

        AmiTCP SDK v4.3 (http://www.aminet.net/comm/tcp/AmiTCP-SDK-4.3.lha)

        Native Developer Kit (http://www.amiga.com/3.9/download/NDK3.9.lha)

   As no ixemul.library is required you will be able to build it for
   WarpOS/PowerPC (not tested by me), as well a MorphOS version should be
   possible with no problems.

   To enable SSL support, you need a OpenSSL native version (without ixemul),
   you can find a precompiled package at http://amiga.sourceforge.net/OpenSSL/


NetWare
=======
   To compile c-ares.nlm / libc-ares.nlm you need:
   - either any gcc / nlmconv, or CodeWarrior 7 PDK 4 or later.
   - gnu make and awk running on the platform you compile on;
     native Win32 versions can be downloaded from:
     http://www.gknw.net/development/prgtools/
   - recent Novell LibC SDK available from:
     http://developer.novell.com/ndk/libc.htm
   - or recent Novell CLib SDK available from:
     http://developer.novell.com/ndk/clib.htm

   Set a search path to your compiler, linker and tools; on Linux make
   sure that the var OSTYPE contains the string 'linux'; set the var
   NDKBASE to point to the base of your Novell NDK; and then type
   'make netware' from the top source directory; other targets available
   are 'netware-ssl', 'netware-ssl-zlib', 'netware-zlib' and 'netware-ares';
   if you need other combinations you can control the build with the
   environment variables WITH_SSL, WITH_ZLIB, WITH_ARES, WITH_SSH2, and
   ENABLE_IPV6; you can set LINK_STATIC=1 to link c-ares.nlm statically.
   By default LDAP support is enabled, however currently you will need a patch
   in order to use the CLDAP NDK with BSD sockets (Novell Bug 300237):
   http://www.gknw.net/test/c-ares/cldap_ndk/ldap_ndk.diff
   I found on some Linux systems (RH9) that OS detection didn't work although
   a 'set | grep OSTYPE' shows the var present and set; I simply overwrote it
   with 'OSTYPE=linux-rh9-gnu' and the detection in the Makefile worked...
   Any help in testing appreciated!
   Builds automatically created 8 times a day from current git are here:
   http://www.gknw.net/mirror/c-ares/autobuilds/
   the status of these builds can be viewed at the autobuild table:
   http://c-ares.haxx.se/dev/builds.html


eCos
====
   c-ares does not use the eCos build system, so you must first build eCos
   separately, then link c-ares to the resulting eCos library.  Here's a sample
   configure line to do so on an x86 Linux box targeting x86:

   GCCLIB=`gcc -print-libgcc-file-name` && \
   CFLAGS="-D__ECOS=1 -nostdinc -I$ECOS_INSTALL/include \
    -I`dirname $GCCLIB`/include" \
   LDFLAGS="-nostdlib -Wl,--gc-sections -Wl,-static \
    -L$ECOS_INSTALL/lib -Ttarget.ld -ltarget" \
   ./configure --host=i386 --disable-shared \
    --without-ssl --without-zlib --disable-manual --disable-ldap

   In most cases, eCos users will be using libc-ares from within a custom
   embedded application.  Using the standard 'c-ares' executable from
   within eCos means facing the limitation of the standard eCos C
   startup code which does not allow passing arguments in main().  To
   run 'c-ares' from eCos and have it do something useful, you will need
   to either modify the eCos startup code to pass in some arguments, or
   modify the c-ares application itself to retrieve its arguments from
   some location set by the bootloader or hard-code them.

   Something like the following patch could be used to hard-code some
   arguments.  The MTAB_ENTRY line mounts a RAM disk as the root filesystem
   (without mounting some kind of filesystem, eCos errors out all file
   operations which c-ares does not take to well).  The next section synthesizes
   some command-line arguments for c-ares to use, in this case to direct c-ares
   to read further arguments from a file.  It then creates that file on the
   RAM disk and places within it a URL to download: a file: URL that
   just happens to point to the configuration file itself.  The results
   of running c-ares in this way is the contents of the configuration file
   printed to the console.

--- src/main.c  19 Jul 2006 19:09:56 -0000    1.363
+++ src/main.c  24 Jul 2006 21:37:23 -0000
@@ -4286,11 +4286,31 @@
 }


+#ifdef __ECOS
+#include <cyg/fileio/fileio.h>
+MTAB_ENTRY( testfs_mte1,
+                   "/",
+                   "ramfs",
+                   "",
+                   0);
+#endif

 int main(int argc, char *argv[])
 {
   int res;
   struct Configurable config;
+#ifdef __ECOS
+  char *args[] = {"ecos-c-ares", "-K", "c-aresconf.txt"};
+  FILE *f;
+  argc = sizeof(args)/sizeof(args[0]);
+  argv = args;
+
+  f = fopen("c-aresconf.txt", "w");
+  if (f) {
+    fprintf(f, "--url file:c-aresconf.txt");
+    fclose(f);
+  }
+#endif
   memset(&config, 0, sizeof(struct Configurable));

   config.errors = stderr; /* default errors to stderr */


Minix
=====
   c-ares can be compiled on Minix 3 using gcc or ACK (starting with
   ver. 3.1.3).  Ensure that GNU gawk and bash are both installed and
   available in the PATH.

   ACK
   ---
   Increase the heap sizes of the compiler with the command:

     binsizes xxl

   then configure and compile c-ares with:

     ./configure CC=cc LD=cc AR=/usr/bin/aal GREP=grep \
      CPPFLAGS='-D_POSIX_SOURCE=1 -I/usr/local/include'
     make
     chmem =256000 src/c-ares

   GCC
   ---
   Make sure gcc is in your PATH with the command:

     export PATH=/usr/gnu/bin:$PATH

   then configure and compile c-ares with:

     ./configure CC=gcc AR=/usr/gnu/bin/gar GREP=grep
     make
     chmem =256000 src/c-ares


Symbian OS
==========
   The Symbian OS port uses the Symbian build system to compile.  From the
   packages/Symbian/group/ directory, run:

      bldmake bldfiles
      abld build

   to compile and install c-ares and libc-ares using SBSv1. If your Symbian
   SDK doesn't include support for P.I.P.S., you will need to contact
   your SDK vendor to obtain that first.


VxWorks
========
   Build for VxWorks is performed using cross compilation.
   That means you build on Windows machine using VxWorks tools and
   run the built image on the VxWorks device.

   To build libc-ares for VxWorks you need:

      - CYGWIN (free, http://cygwin.com/)
      - Wind River Workbench (commercial)

   If you have CYGWIN and Workbench installed on you machine
   follow after next steps:

    1. Open the Command Prompt window and change directory ('cd')
       to the libc-ares 'lib' folder.
    2. Add CYGWIN 'bin' folder to the PATH environment variable.
       For example, type 'set PATH=C:/embedded/cygwin/bin;%PATH%'.
    3. Adjust environment variables defined in 'Environment' section
       of the Makefile.vxworks file to point to your software folders.
    4. Build the libc-ares by typing 'make -f ./Makefile.vxworks'

   As a result the libc-ares.a library should be created in the 'lib' folder.
   To clean the build results type 'make -f ./Makefile.vxworks clean'.


Android
=======
   Method using the static makefile:
      - see the build notes in the Android.mk file.

   Method using a configure cross-compile (tested with Android NDK r7b):
      - prepare the toolchain of the Android NDK for standalone use; this can
        be done by invoking the script:
        ./tools/make-standalone-toolchain.sh
        which creates a usual cross-compile toolchain. Lets assume that you put
        this toolchain below /opt then invoke configure with something like:
        export PATH=/opt/arm-linux-androideabi-4.4.3/bin:$PATH
        ./configure --host=arm-linux-androideabi [more configure options]
        make
      - if you want to compile directly from our GIT repo you might run into
        this issue with older automake stuff:
        checking host system type...
        Invalid configuration `arm-linux-androideabi':
        system `androideabi' not recognized
        configure: error: /bin/sh ./config.sub arm-linux-androideabi failed
        this issue can be fixed with using more recent versions of config.sub
        and config.guess which can be obtained here:
        http://git.savannah.gnu.org/gitweb/?p=config.git;a=tree
        you need to replace your system-own versions which usually can be
        found in your automake folder:
        find /usr -name config.sub


CROSS COMPILE
=============
   (This section was graciously brought to us by Jim Duey, with additions by
   Dan Fandrich)

   Download and unpack the cURL package.

   'cd' to the new directory. (e.g. cd c-ares-7.12.3)

   Set environment variables to point to the cross-compile toolchain and call
   configure with any options you need.  Be sure and specify the '--host' and
   '--build' parameters at configuration time.  The following script is an
   example of cross-compiling for the IBM 405GP PowerPC processor using the
   toolchain from MonteVista for Hardhat Linux.

   (begin script)

   #! /bin/sh

   export PATH=$PATH:/opt/hardhat/devkit/ppc/405/bin
   export CPPFLAGS="-I/opt/hardhat/devkit/ppc/405/target/usr/include"
   export AR=ppc_405-ar
   export AS=ppc_405-as
   export LD=ppc_405-ld
   export RANLIB=ppc_405-ranlib
   export CC=ppc_405-gcc
   export NM=ppc_405-nm

   ./configure --target=powerpc-hardhat-linux \
        --host=powerpc-hardhat-linux \
        --build=i586-pc-linux-gnu \
        --prefix=/opt/hardhat/devkit/ppc/405/target/usr/local \
        --exec-prefix=/usr/local

   (end script)

   You may also need to provide a parameter like '--with-random=/dev/urandom'
   to configure as it cannot detect the presence of a random number
   generating device for a target system.  The '--prefix' parameter
   specifies where cURL will be installed.  If 'configure' completes
   successfully, do 'make' and 'make install' as usual.

   In some cases, you may be able to simplify the above commands to as
   little as:

       ./configure --host=ARCH-OS


REDUCING SIZE
=============
   There are a number of configure options that can be used to reduce the
   size of libc-ares for embedded applications where binary size is an
   important factor.  First, be sure to set the CFLAGS variable when
   configuring with any relevant compiler optimization flags to reduce the
   size of the binary.  For gcc, this would mean at minimum the -Os option,
   and potentially the -march=X and -mdynamic-no-pic options as well, e.g.

      ./configure CFLAGS='-Os' ...

   Note that newer compilers often produce smaller code than older versions
   due to improved optimization.

   Be sure to specify as many --disable- and --without- flags on the configure
   command-line as you can to disable all the libc-ares features that you
   know your application is not going to need.  Besides specifying the
   --disable-PROTOCOL flags for all the types of URLs your application
   will not use, here are some other flags that can reduce the size of the
   library:

     --disable-ares (disables support for the C-ARES DNS library)
     --disable-cookies (disables support for HTTP cookies)
     --disable-crypto-auth (disables HTTP cryptographic authentication)
     --disable-ipv6 (disables support for IPv6)
     --disable-manual (disables support for the built-in documentation)
     --disable-proxy (disables support for HTTP and SOCKS proxies)
     --disable-verbose (eliminates debugging strings and error code strings)
     --enable-hidden-symbols (eliminates unneeded symbols in the shared library)
     --without-libidn (disables support for the libidn DNS library)
     --without-ssl (disables support for SSL/TLS)
     --without-zlib (disables support for on-the-fly decompression)

   The GNU compiler and linker have a number of options that can reduce the
   size of the libc-ares dynamic libraries on some platforms even further.
   Specify them by providing appropriate CFLAGS and LDFLAGS variables on the
   configure command-line:
     CFLAGS="-ffunction-sections -fdata-sections" \
     LDFLAGS="-Wl,-s -Wl,-Bsymbolic -Wl,--gc-sections"

   Be sure also to strip debugging symbols from your binaries after
   compiling using 'strip' (or the appropriate variant if cross-compiling).
   If space is really tight, you may be able to remove some unneeded
   sections of the shared library using the -R option to objcopy (e.g. the
   .comment section).

   Using these techniques it is possible to create a basic HTTP-only shared
   libc-ares library for i386 Linux platforms that is only 101 KiB in size, and
   an FTP-only library that is 105 KiB in size (as of libc-ares version 7.21.5,
   using gcc 4.4.3).

   You may find that statically linking libc-ares to your application will
   result in a lower total size than dynamically linking.

   Note that the c-ares test harness can detect the use of some, but not all, of
   the --disable statements suggested above. Use will cause tests relying on
   those features to fail.  The test harness can be manually forced to skip
   the relevant tests by specifying certain key words on the runtests.pl
   command line.  Following is a list of appropriate key words:

     --disable-cookies          !cookies
     --disable-crypto-auth      !HTTP\ Digest\ auth !HTTP\ proxy\ Digest\ auth
     --disable-manual           !--manual
     --disable-proxy            !HTTP\ proxy !proxytunnel !SOCKS4 !SOCKS5


PORTS
=====
   This is a probably incomplete list of known hardware and operating systems
   that c-ares has been compiled for. If you know a system c-ares compiles and
   runs on, that isn't listed, please let us know!

        - Alpha DEC OSF 4
        - Alpha Digital UNIX v3.2
        - Alpha FreeBSD 4.1, 4.5
        - Alpha Linux 2.2, 2.4
        - Alpha NetBSD 1.5.2
        - Alpha OpenBSD 3.0
        - Alpha OpenVMS V7.1-1H2
        - Alpha Tru64 v5.0 5.1
        - AVR32 Linux
        - ARM Android 1.5, 2.1, 2.3
        - ARM INTEGRITY
        - ARM iPhone OS
        - Cell Linux
        - Cell Cell OS
        - HP-PA HP-UX 9.X 10.X 11.X
        - HP-PA Linux
        - HP3000 MPE/iX
        - MicroBlaze uClinux
        - MIPS IRIX 6.2, 6.5
        - MIPS Linux
        - OS/400
        - Pocket PC/Win CE 3.0
        - Power AIX 3.2.5, 4.2, 4.3.1, 4.3.2, 5.1, 5.2
        - PowerPC Darwin 1.0
        - PowerPC INTEGRITY
        - PowerPC Linux
        - PowerPC Mac OS 9
        - PowerPC Mac OS X
        - SH4 Linux 2.6.X
        - SH4 OS21
        - SINIX-Z v5
        - Sparc Linux
        - Sparc Solaris 2.4, 2.5, 2.5.1, 2.6, 7, 8, 9, 10
        - Sparc SunOS 4.1.X
        - StrongARM (and other ARM) RISC OS 3.1, 4.02
        - StrongARM/ARM7/ARM9 Linux 2.4, 2.6
        - StrongARM NetBSD 1.4.1
        - Symbian OS (P.I.P.S.) 9.x
        - TPF
        - Ultrix 4.3a
        - UNICOS 9.0
        - i386 BeOS
        - i386 DOS
        - i386 eCos 1.3.1
        - i386 Esix 4.1
        - i386 FreeBSD
        - i386 HURD
        - i386 Haiku OS
        - i386 Linux 1.3, 2.0, 2.2, 2.3, 2.4, 2.6
        - i386 MINIX 3.1
        - i386 NetBSD
        - i386 Novell NetWare
        - i386 OS/2
        - i386 OpenBSD
        - i386 QNX 6
        - i386 SCO unix
        - i386 Solaris 2.7
        - i386 Windows 95, 98, ME, NT, 2000, XP, 2003
        - i486 ncr-sysv4.3.03 (NCR MP-RAS)
        - ia64 Linux 2.3.99
        - m68k AmigaOS 3
        - m68k Linux
        - m68k uClinux
        - m68k OpenBSD
        - m88k dg-dgux5.4R3.00
        - s390 Linux
        - x86_64 Linux
        - XScale/PXA250 Linux 2.4
        - Nios II uClinux

Useful URLs
===========

axTLS        http://axtls.sourceforge.net/
c-ares       http://c-ares.haxx.se/
GNU GSS      http://www.gnu.org/software/gss/
GnuTLS       http://www.gnu.org/software/gnutls/
Heimdal      http://www.pdc.kth.se/heimdal/
libidn       http://www.gnu.org/software/libidn/
libssh2      http://www.libssh2.org/
MIT Kerberos http://web.mit.edu/kerberos/www/dist/
NSS          http://www.mozilla.org/projects/security/pki/nss/
OpenLDAP     http://www.openldap.org/
OpenSSL      http://www.openssl.org/
PolarSSL     http://polarssl.org/
yassl        http://www.yassl.com/
Zlib         http://www.zlib.net/

MingW        http://www.mingw.org/
MinGW-w64    http://mingw-w64.sourceforge.net/
OpenWatcom   http://www.openwatcom.org/