This is Python version 2.7 alpha 0==================================Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009Python Software Foundation.All rights reserved.Copyright (c) 2000 BeOpen.com.All rights reserved.Copyright (c) 1995-2001 Corporation for National Research Initiatives.All rights reserved.Copyright (c) 1991-1995 Stichting Mathematisch Centrum.All rights reserved.License information-------------------See the file "LICENSE" for information on the history of thissoftware, terms & conditions for usage, and a DISCLAIMER OF ALLWARRANTIES.This Python distribution contains no GNU General Public Licensed(GPLed) code so it may be used in proprietary projects just like priorPython distributions.  There are interfaces to some GNU code but theseare entirely optional.All trademarks referenced herein are property of their respectiveholders.What's new in this release?---------------------------See the file "Misc/NEWS".If you don't read instructions------------------------------Congratulations on getting this far. :-)To start building right away (on UNIX): type "./configure" in thecurrent directory and when it finishes, type "make".  This creates anexecutable "./python"; to install in /usr/local, first do "su root"and then "make install".The section `Build instructions' below is still recommended reading.What is Python anyway?----------------------Python is an interpreted, interactive object-oriented programminglanguage suitable (amongst other uses) for distributed applicationdevelopment, scripting, numeric computing and system testing.  Pythonis often compared to Tcl, Perl, Java, JavaScript, Visual Basic orScheme.  To find out more about what Python can do for you, point yourbrowser tohttp://www.python.org/.How do I learn Python?----------------------The official tutorial is still a good place to start; seehttp://docs.python.org/ for online and downloadable versions, as wellas a list of other introductions, and reference documentation.There's a quickly growing set of books on Python.  Seehttp://wiki.python.org/moin/PythonBooks for a list.Documentation-------------All documentation is provided online in a variety of formats.  Inorder of importance for new users: Tutorial, Library Reference,Language Reference, Extending & Embedding, and the Python/C API.  TheLibrary Reference is especially of immense value since much ofPython's power is described there, including the built-in data typesand functions!All documentation is also available online at the Python web site(http://docs.python.org/, see below).  It is available online for occasionalreference, or can be downloaded in many formats for faster access.  Thedocumentation is downloadable in HTML, PostScript, PDF, LaTeX, andreStructuredText (2.6+) formats; the LaTeX and reStructuredText versions areprimarily for documentation authors, translators, and people with specialformatting requirements.Web sites---------New Python releases and related technologies are published athttp://www.python.org/.  Come visit us!There's also a Python community web site athttp://starship.python.net/.Newsgroups and Mailing Lists----------------------------Read comp.lang.python, a high-volume discussion newsgroup aboutPython, or comp.lang.python.announce, a low-volume moderated newsgroupfor Python-related announcements.  These are also accessible asmailing lists: seehttp://www.python.org/community/lists.html for anoverview of these and many other Python-related mailing lists.Archives are accessible via the Google Groups Usenet archive; seehttp://groups.google.com/.  The mailing lists are also archived, seehttp://www.python.org/community/lists.html for details.Bug reports-----------To report or search for bugs, please use the Python BugTracker athttp://bugs.python.org.Patches and contributions-------------------------To submit a patch or other contribution, please use the Python PatchManager athttp://bugs.python.org.  Guidelinesfor patch submission may be found athttp://www.python.org/dev/patches/.If you have a proposal to change Python, you may want to send an email to thecomp.lang.python or python-ideas mailing lists for inital feedback. A PythonEnhancement Proposal (PEP) may be submitted if your idea gains ground. Allcurrent PEPs, as well as guidelines for submitting a new PEP, are listed athttp://www.python.org/dev/peps/.Questions---------For help, if you can't find it in the manuals or on the web site, it'sbest to post to the comp.lang.python or the Python mailing list (seeabove).  If you specifically don't want to involve the newsgroup ormailing list, send questions to help@python.org (a group of volunteerswho answer questions as they can).  The newsgroup is the mostefficient way to ask public questions.Build instructions==================Before you can build Python, you must first configure it.Fortunately, the configuration and build process has been automatedfor Unix and Linux installations, so all you usually have to do istype a few commands and sit back.  There are some platforms wherethings are not quite as smooth; see the platform specific notes below.If you want to build for multiple platforms sharing the same sourcetree, see the section on VPATH below.Start by running the script "./configure", which determines yoursystem configuration and creates the Makefile.  (It takes a minute ortwo -- please be patient!)  You may want to pass options to theconfigure script -- see the section below on configuration options andvariables.  When it's done, you are ready to run make.To build Python, you normally type "make" in the toplevel directory.If you have changed the configuration, the Makefile may have to berebuilt.  In this case you may have to run make again to correctlybuild your desired target.  The interpreter executable is built in thetop level directory.Once you have built a Python interpreter, see the subsections below ontesting and installation.  If you run into trouble, see the nextsection.Previous versions of Python used a manual configuration process thatinvolved editing the file Modules/Setup.  While this file still existsand manual configuration is still supported, it is rarely needed anymore: almost all modules are automatically built as appropriate underguidance of the setup.py script, which is run by Make after theinterpreter has been built.Troubleshooting---------------See also the platform specific notes in the next section.If you run into other trouble, see the FAQ(http://www.python.org/doc/faq) for hints on what can go wrong, andhow to fix it.If you rerun the configure script with different options, remove allobject files by running "make clean" before rebuilding.  Believe it ornot, "make clean" sometimes helps to clean up other inexplicableproblems as well.  Try it before sending in a bug report!If the configure script fails or doesn't seem to find things thatshould be there, inspect the config.log file.If you get a warning for every file about the -Olimit option being nolonger supported, you can ignore it.  There's no foolproof way to knowwhether this option is needed; all we can do is test whether it isaccepted without error.  On some systems, e.g. older SGI compilers, itis essential for performance (specifically when compiling ceval.c,which has more basic blocks than the default limit of 1000).  If thewarning bothers you, edit the Makefile to remove "-Olimit 1500" fromthe OPT variable.If you get failures in test_long, or sys.maxint gets set to -1, youare probably experiencing compiler bugs, usually related tooptimization.  This is a common problem with some versions of gcc, andsome vendor-supplied compilers, which can sometimes be worked aroundby turning off optimization.  Consider switching to stable versions(gcc 2.95.2, gcc 3.x, or contact your vendor.)From Python 2.0 onward, all Python C code is ANSI C.  Compiling usingold K&R-C-only compilers is no longer possible.  ANSI C compilers areavailable for all modern systems, either in the form of updatedcompilers from the vendor, or one of the free compilers (gcc).If "make install" fails mysteriously during the "compiling the library"step, make sure that you don't have any of the PYTHONPATH or PYTHONHOMEenvironment variables set, as they may interfere with the newly builtexecutable which is compiling the library.Unsupported systems-------------------A number of features are not supported in Python 2.5 anymore. Somesupport code is still present, but will be removed in Python 2.6. If you still need to use current Python versions on these systems,please send a message to python-dev@python.org indicating that youvolunteer to support this system. For a more detailed discussion regarding no-longer-supported and resupporting platforms, as wellas a list of platforms that became or will be unsupported, see PEP 11.More specifically, the following systems are not supported anylonger:- SunOS 4- DYNIX- dgux- Minix- NeXT- Irix 4 and --with-sgi-dl- Linux 1- Systems defining __d6_pthread_create (configure.in)- Systems defining PY_PTHREAD_D4, PY_PTHREAD_D6,  or PY_PTHREAD_D7 in thread_pthread.h- Systems using --with-dl-dld- Systems using --without-universal-newlines- MacOS 9The following systems are still supported in Python 2.5, butsupport will be dropped in 2.6:- Systems using --with-wctype-functions- Win9x, WinMEWarning on install in Windows 98 and Windows Me-----------------------------------------------Following Microsoft's closing of Extended Support forWindows 98/ME (July 11, 2006), Python 2.6 will stopsupporting these platforms. Python development andmaintainability becomes easier (and more reliable) whenplatform specific code targeting OSes with few usersand no dedicated expert developers is taken out. Thevendor also warns that the OS versions listed above"can expose customers to security risks" and recommendsupgrade.Platform specific notes-----------------------(Some of these may no longer apply.  If you find you can build Pythonon these platforms without the special directions mentioned here,submit a documentation bug report to SourceForge (see Bug Reportsabove) so we can remove them!)Unix platforms: If your vendor still ships (and you still use) Berkeley DB        1.85 you will need to edit Modules/Setup to build the bsddb185        module and add a line to sitecustomize.py which makes it the        default.  In Modules/Setup a line like            bsddb185 bsddbmodule.c        should work.  (You may need to add -I, -L or -l flags to direct the        compiler and linker to your include files and libraries.)XXX I think this next bit is out of date:64-bit platforms: The modules audioop, and imageop don't work.        The setup.py script disables them on 64-bit installations.        Don't try to enable them in the Modules/Setup file.  They        contain code that is quite wordsize sensitive.  (If you have a        fix, let us know!)Solaris: When using Sun's C compiler with threads, at least on Solaris        2.5.1, you need to add the "-mt" compiler option (the simplest        way is probably to specify the compiler with this option as        the "CC" environment variable when running the configure        script).        When using GCC on Solaris, beware of binutils 2.13 or GCC        versions built using it.  This mistakenly enables the        -zcombreloc option which creates broken shared libraries on        Solaris.  binutils 2.12 works, and the binutils maintainers        are aware of the problem.  Binutils 2.13.1 only partially        fixed things.  It appears that 2.13.2 solves the problem        completely.  This problem is known to occur with Solaris 2.7        and 2.8, but may also affect earlier and later versions of the        OS.        When the dynamic loader complains about errors finding shared        libraries, such as        ld.so.1: ./python: fatal: libstdc++.so.5: open failed:        No such file or directory        you need to first make sure that the library is available on        your system. Then, you need to instruct the dynamic loader how        to find it. You can choose any of the following strategies:        1. When compiling Python, set LD_RUN_PATH to the directories           containing missing libraries.        2. When running Python, set LD_LIBRARY_PATH to these directories.        3. Use crle(8) to extend the search path of the loader.        4. Modify the installed GCC specs file, adding -R options into the           *link: section.        The complex object fails to compile on Solaris 10 with gcc 3.4 (at        least up to 3.4.3).  To work around it, define Py_HUGE_VAL as        HUGE_VAL(), e.g.:          make CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()" -I. -I$(srcdir)/Include'          ./python setup.py CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()"'Linux:  A problem with threads and fork() was tracked down to a bug in        the pthreads code in glibc version 2.0.5; glibc version 2.0.7        solves the problem.  This causes the popen2 test to fail;        problem and solution reported by Pablo Bleyer.Red Hat Linux: Red Hat 9 built Python2.2 in UCS-4 mode and hacked        Tcl to support it. To compile Python2.3 with Tkinter, you will        need to pass --enable-unicode=ucs4 flag to ./configure.        There's an executable /usr/bin/python which is Python        1.5.2 on most older Red Hat installations; several key Red Hat tools        require this version.  Python 2.1.x may be installed as        /usr/bin/python2.  The Makefile installs Python as        /usr/local/bin/python, which may or may not take precedence        over /usr/bin/python, depending on how you have set up $PATH.FreeBSD 3.x and probably platforms with NCurses that use libmytinfo or        similar: When using cursesmodule, the linking is not done in        the correct order with the defaults.  Remove "-ltermcap" from        the readline entry in Setup, and use as curses entry: "curses        cursesmodule.c -lmytinfo -lncurses -ltermcap" - "mytinfo" (so        called on FreeBSD) should be the name of the auxiliary library        required on your platform.  Normally, it would be linked        automatically, but not necessarily in the correct order.BSDI:   BSDI versions before 4.1 have known problems with threads,        which can cause strange errors in a number of modules (for        instance, the 'test_signal' test script will hang forever.)        Turning off threads (with --with-threads=no) or upgrading to        BSDI 4.1 solves this problem.DEC Unix: Run configure with --with-dec-threads, or with        --with-threads=no if no threads are desired (threads are on by        default).  When using GCC, it is possible to get an internal        compiler error if optimization is used.  This was reported for        GCC 2.7.2.3 on selectmodule.c.  Manually compile the affected        file without optimization to solve the problem.DEC Ultrix: compile with GCC to avoid bugs in the native compiler,        and pass SHELL=/bin/sh5 to Make when installing.AIX:    A complete overhaul of the shared library support is now in        place.  See Misc/AIX-NOTES for some notes on how it's done.        (The optimizer bug reported at this place in previous releases        has been worked around by a minimal code change.) If you get        errors about pthread_* functions, during compile or during        testing, try setting CC to a thread-safe (reentrant) compiler,        like "cc_r".  For full C++ module support, set CC="xlC_r" (or        CC="xlC" without thread support).AIX 5.3: To build a 64-bit version with IBM's compiler, I used the        following:        export PATH=/usr/bin:/usr/vacpp/bin        ./configure --with-gcc="xlc_r -q64" --with-cxx="xlC_r -q64" \                    --disable-ipv6 AR="ar -X64"        makeHP-UX:  When using threading, you may have to add -D_REENTRANT to the        OPT variable in the top-level Makefile; reported by Pat Knight,        this seems to make a difference (at least for HP-UX 10.20)        even though pyconfig.h defines it. This seems unnecessary when        using HP/UX 11 and later - threading seems to work "out of the        box".HP-UX ia64: When building on the ia64 (Itanium) platform using HP's        compiler, some experience has shown that the compiler's        optimiser produces a completely broken version of python        (seehttp://www.python.org/sf/814976). To work around this,        edit the Makefile and remove -O from the OPT line.        To build a 64-bit executable on an Itanium 2 system using HP's        compiler, use these environment variables:                CC=cc                CXX=aCC                BASECFLAGS="+DD64"                LDFLAGS="+DD64 -lxnet"        and call configure as:                ./configure --without-gcc        then *unset* the environment variables again before running        make.  (At least one of these flags causes the build to fail        if it remains set.)  You still have to edit the Makefile and        remove -O from the OPT line.HP PA-RISC 2.0: A recent bug report (http://www.python.org/sf/546117)        suggests that the C compiler in this 64-bit system has bugs        in the optimizer that break Python.  Compiling without        optimization solves the problems.SCO:    The following apply to SCO 3 only; Python builds out of the box        on SCO 5 (or so we've heard).        1) Everything works much better if you add -U__STDC__ to the        defs.  This is because all the SCO header files are broken.        Anything that isn't mentioned in the C standard is        conditionally excluded when __STDC__ is defined.        2) Due to the U.S. export restrictions, SCO broke the crypt        stuff out into a separate library, libcrypt_i.a so the LIBS        needed be set to:                LIBS=' -lsocket -lcrypt_i'UnixWare: There are known bugs in the math library of the system, as well as        problems in the handling of threads (calling fork in one        thread may interrupt system calls in others). Therefore, test_math and        tests involving threads will fail until those problems are fixed.QNX:    Chris Herborth (chrish@qnx.com) writes:        configure works best if you use GNU bash; a port is available on        ftp.qnx.com in /usr/free.  I used the following process to build,        test and install Python 1.5.x under QNX:        1) CONFIG_SHELL=/usr/local/bin/bash CC=cc RANLIB=: \            ./configure --verbose --without-gcc --with-libm=""        2) edit Modules/Setup to activate everything that makes sense for           your system... tested here at QNX with the following modules:                array, audioop, binascii, cPickle, cStringIO, cmath,                crypt, curses, errno, fcntl, gdbm, grp, imageop,                _locale, math, md5, new, operator, parser, pcre,                posix, pwd, readline, regex, reop,                select, signal, socket, soundex, strop, struct,                syslog, termios, time, timing, zlib, audioop, imageop        3) make SHELL=/usr/local/bin/bash           or, if you feel the need for speed:           make SHELL=/usr/local/bin/bash OPT="-5 -Oil+nrt"        4) make SHELL=/usr/local/bin/bash test           Using GNU readline 2.2 seems to behave strangely, but I           think that's a problem with my readline 2.2 port.  :-\        5) make SHELL=/usr/local/bin/bash install        If you get SIGSEGVs while running Python (I haven't yet, but        I've only run small programs and the test cases), you're        probably running out of stack; the default 32k could be a        little tight.  To increase the stack size, edit the Makefile        to read: LDFLAGS = -N 48kBeOS:   See Misc/BeOS-NOTES for notes about compiling/installing        Python on BeOS R3 or later.  Note that only the PowerPC        platform is supported for R3; both PowerPC and x86 are        supported for R4.Cray T3E: Mark Hadfield (m.hadfield@niwa.co.nz) writes:        Python can be built satisfactorily on a Cray T3E but based on        my experience with the NIWA T3E (2002-05-22, version 2.2.1)        there are a few bugs and gotchas. For more information see a        thread on comp.lang.python in May 2002 entitled "Building        Python on Cray T3E".        1) Use Cray's cc and not gcc. The latter was reported not to           work by Konrad Hinsen. It may work now, but it may not.        2) To set sys.platform to something sensible, pass the           following environment variable to the configure script:             MACHDEP=unicosmk        2) Run configure with option "--enable-unicode=ucs4".        3) The Cray T3E does not support dynamic linking, so extension           modules have to be built by adding (or uncommenting) lines           in Modules/Setup. The minimum set of modules is             posix, new, _sre, unicodedata           On NIWA's vanilla T3E system the following have also been           included successfully:             _codecs, _locale, _socket, _symtable, _testcapi, _weakref             array, binascii, cmath, cPickle, crypt, cStringIO, dbm             errno, fcntl, grp, math, md5, operator, parser, pcre, pwd             regex, rotor, select, struct, strop, syslog, termios             time, timing, xreadlines        4) Once the python executable and library have been built, make           will execute setup.py, which will attempt to build remaining           extensions and link them dynamically. Each of these attempts           will fail but should not halt the make process. This is           normal.        5) Running "make test" uses a lot of resources and causes           problems on our system. You might want to try running tests           singly or in small groups.SGI:    SGI's standard "make" utility (/bin/make or /usr/bin/make)        does not check whether a command actually changed the file it        is supposed to build.  This means that whenever you say "make"        it will redo the link step.  The remedy is to use SGI's much        smarter "smake" utility (/usr/sbin/smake), or GNU make.  If        you set the first line of the Makefile to #!/usr/sbin/smake        smake will be invoked by make (likewise for GNU make).        WARNING: There are bugs in the optimizer of some versions of        SGI's compilers that can cause bus errors or other strange        behavior, especially on numerical operations.  To avoid this,        try building with "make OPT=".OS/2:   If you are running Warp3 or Warp4 and have IBM's VisualAge C/C++        compiler installed, just change into the pc\os2vacpp directory        and type NMAKE.  Threading and sockets are supported by default        in the resulting binaries of PYTHON15.DLL and PYTHON.EXE.Monterey (64-bit AIX): The current Monterey C compiler (Visual Age)        uses the OBJECT_MODE={32|64} environment variable to set the        compilation mode to either 32-bit or 64-bit (32-bit mode is        the default).  Presumably you want 64-bit compilation mode for        this 64-bit OS.  As a result you must first set OBJECT_MODE=64        in your environment before configuring (./configure) or        building (make) Python on Monterey.Reliant UNIX: The thread support does not compile on Reliant UNIX, and        there is a (minor) problem in the configure script for that        platform as well.  This should be resolved in time for a        future release.MacOSX: The tests will crash on both 10.1 and 10.2 with SEGV in        test_re and test_sre due to the small default stack size.  If        you set the stack size to 2048 before doing a "make test" the        failure can be avoided.  If you're using the tcsh or csh shells,        use "limit stacksize 2048" and for the bash shell (the default        as of OSX 10.3), use "ulimit -s 2048".        On naked Darwin you may want to add the configure option        "--disable-toolbox-glue" to disable the glue code for the Carbon        interface modules. The modules themselves are currently only built        if you add the --enable-framework option, see below.        On a clean OSX /usr/local does not exist. Do a        "sudo mkdir -m 775 /usr/local"        before you do a make install. It is probably not a good idea to        do "sudo make install" which installs everything as superuser,        as this may later cause problems when installing distutils-based        additions.        Some people have reported problems building Python after using "fink"        to install additional unix software. Disabling fink (remove all         references to /sw from your .profile or .login) should solve this.        You may want to try the configure option "--enable-framework"        which installs Python as a framework. The location can be set        as argument to the --enable-framework option (default        /Library/Frameworks). A framework install is probably needed if you        want to use any Aqua-based GUI toolkit (whether Tkinter, wxPython,        Carbon, Cocoa or anything else).        You may also want to try the configure option "--enable-universalsdk"        which builds Python as a universal binary with support for the         i386 and PPC architetures. This requires Xcode 2.1 or later to build.        See Mac/README for more information on framework and         universal builds.Cygwin: With recent (relative to the time of writing, 2001-12-19)        Cygwin installations, there are problems with the interaction        of dynamic linking and fork().  This manifests itself in build        failures during the execution of setup.py.        There are two workarounds that both enable Python (albeit        without threading support) to build and pass all tests on        NT/2000 (and most likely XP as well, though reports of testing        on XP would be appreciated).        The workarounds:        (a) the band-aid fix is to link the _socket module statically        rather than dynamically (which is the default).        To do this, run "./configure --with-threads=no" including any        other options you need (--prefix, etc.).  Then in Modules/Setup        uncomment the lines:        #SSL=/usr/local/ssl        #_socket socketmodule.c \        #       -DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \        #       -L$(SSL)/lib -lssl -lcrypto        and remove "local/" from the SSL variable.  Finally, just run        "make"!        (b) The "proper" fix is to rebase the Cygwin DLLs to prevent        base address conflicts.  Details on how to do this can be        found in the following mail:http://sources.redhat.com/ml/cygwin/2001-12/msg00894.html        It is hoped that a version of this solution will be        incorporated into the Cygwin distribution fairly soon.        Two additional problems:        (1) Threading support should still be disabled due to a known        bug in Cygwin pthreads that causes test_threadedtempfile to        hang.        (2) The _curses module does not build.  This is a known        Cygwin ncurses problem that should be resolved the next time        that this package is released.        On older versions of Cygwin, test_poll may hang and test_strftime        may fail.        The situation on 9X/Me is not accurately known at present.        Some time ago, there were reports that the following        regression tests failed:            test_pwd            test_select (hang)            test_socket        Due to the test_select hang on 9X/Me, one should run the        regression test using the following:            make TESTOPTS='-l -x test_select' test        News regarding these platforms with more recent Cygwin        versions would be appreciated!AtheOS: Official support has been stopped as of Python 2.6.  All code will be        removed in Python 2.7 unless a maintainer steps forward for this        platform.        From Octavian Cerna <tavy at ylabs.com>:        Before building:            Make sure you have shared versions of the libraries you            want to use with Python. You will have to compile them            yourself, or download precompiled packages.            Recommended libraries:                ncurses-4.2                readline-4.2a                zlib-1.1.4        Build:            $ ./configure --prefix=/usr/python            $ make            Python is always built as a shared library, otherwise            dynamic loading would not work.        Testing:            $ make test        Install:            # make install            # pkgmanager -a /usr/python        AtheOS issues:            - large file support: due to a stdio bug in glibc/libio,              access to large files may not work correctly.  fseeko()              tries to seek to a negative offset.  ftello() returns a              negative offset, it looks like a 32->64bit              sign-extension issue.  The lowlevel functions (open,              lseek, etc) are OK.            - sockets: AF_UNIX is defined in the C library and in              Python, but not implemented in the system.            - select: poll is available in the C library, but does not              work (It does not return POLLNVAL for bad fds and              hangs).            - posix: statvfs and fstatvfs always return ENOSYS.            - disabled modules:                - mmap: not yet implemented in AtheOS                - nis: broken (on an unconfigured system                  yp_get_default_domain() returns junk instead of                  error)                - dl: dynamic loading doesn't work via dlopen()                - resource: getrimit and setrlimit are not yet                  implemented            - if you are getting segmentation faults, you probably are              low on memory.  AtheOS doesn't handle very well an              out-of-memory condition and simply SEGVs the process.        Tested on:            AtheOS-0.3.7            gcc-2.95            binutils-2.10            make-3.78Configuring the bsddb and dbm modules-------------------------------------Beginning with Python version 2.3, the PyBsddb package<http://pybsddb.sf.net/> was adopted into Python as the bsddb package,exposing a set of package-level functions which providebackwards-compatible behavior.  Only versions 3.3 through 4.4 ofSleepycat's libraries provide the necessary API, so older versionsaren't supported through this interface.  The old bsddb module hasbeen retained as bsddb185, though it is not built by default.  Userswishing to use it will have to tweak Modules/Setup to build it.  Thedbm module will still be built against the Sleepycat libraries ifother preferred alternatives (ndbm, gdbm) are not found.Building the sqlite3 module---------------------------To build the sqlite3 module, you'll need the sqlite3 or libsqlite3packages installed, including the header files. Many modern operatingsystems distribute the headers in a separate package to the library -often it will be the same name as the main package, but with a -dev or-devel suffix. The version of pysqlite2 that's including in Python needs sqlite3 3.0.8or later. setup.py attempts to check that it can find a correct version.Configuring threads-------------------As of Python 2.0, threads are enabled by default.  If you wish tocompile without threads, or if your thread support is broken, pass the--with-threads=no switch to configure.  Unfortunately, on someplatforms, additional compiler and/or linker options are required forthreads to work properly.  Below is a table of those options,collected by Bill Janssen.  We would love to automate this processmore, but the information below is not enough to write a patch for theconfigure.in file, so manual intervention is required.  If you patchthe configure.in file and are confident that the patch works, pleasesend in the patch.  (Don't bother patching the configure script itself-- it is regenerated each time the configure.in file changes.)Compiler switches for threads.............................The definition of _REENTRANT should be configured automatically, ifthat does not work on your system, or if _REENTRANT is definedincorrectly, please report that as a bug.    OS/Compiler/threads                     Switches for use with threads    (POSIX is draft 10, DCE is draft 4)     compile & link    SunOS 5.{1-5}/{gcc,SunPro cc}/solaris   -mt    SunOS 5.5/{gcc,SunPro cc}/POSIX         (nothing)    DEC OSF/1 3.x/cc/DCE                    -threads            (butenhof@zko.dec.com)    Digital UNIX 4.x/cc/DCE                 -threads            (butenhof@zko.dec.com)    Digital UNIX 4.x/cc/POSIX               -pthread            (butenhof@zko.dec.com)    AIX 4.1.4/cc_r/d7                       (nothing)            (buhrt@iquest.net)    AIX 4.1.4/cc_r4/DCE                     (nothing)            (buhrt@iquest.net)    IRIX 6.2/cc/POSIX                       (nothing)            (robertl@cwi.nl)Linker (ld) libraries and flags for threads...........................................    OS/threads                          Libraries/switches for use with threads    SunOS 5.{1-5}/solaris               -lthread    SunOS 5.5/POSIX                     -lpthread    DEC OSF/1 3.x/DCE                   -lpthreads -lmach -lc_r -lc            (butenhof@zko.dec.com)    Digital UNIX 4.x/DCE                -lpthreads -lpthread -lmach -lexc -lc            (butenhof@zko.dec.com)    Digital UNIX 4.x/POSIX              -lpthread -lmach -lexc -lc            (butenhof@zko.dec.com)    AIX 4.1.4/{draft7,DCE}              (nothing)            (buhrt@iquest.net)    IRIX 6.2/POSIX                      -lpthread            (jph@emilia.engr.sgi.com)Building a shared libpython---------------------------Starting with Python 2.3, the majority of the interpreter can be builtinto a shared library, which can then be used by the interpreterexecutable, and by applications embedding Python. To enable this feature,configure with --enable-shared.If you enable this feature, the same object files will be used to createa static library.  In particular, the static library will contain objectfiles using position-independent code (PIC) on platforms where PIC flagsare needed for the shared library.Configuring additional built-in modules---------------------------------------Starting with Python 2.1, the setup.py script at the top of the sourcedistribution attempts to detect which modules can be built andautomatically compiles them.  Autodetection doesn't always work, soyou can still customize the configuration by editing the Modules/Setupfile; but this should be considered a last resort.  The rest of thissection only applies if you decide to edit the Modules/Setup file.You also need this to enable static linking of certain modules (whichis needed to enable profiling on some systems).This file is initially copied from Setup.dist by the configure script;if it does not exist yet, create it by copying Modules/Setup.distyourself (configure will never overwrite it).  Never edit Setup.dist-- always edit Setup or Setup.local (see below).  Read the comments inthe file for information on what kind of edits are allowed.  When youhave edited Setup in the Modules directory, the interpreter willautomatically be rebuilt the next time you run make (in the topleveldirectory).Many useful modules can be built on any Unix system, but some optionalmodules can't be reliably autodetected.  Often the quickest way todetermine whether a particular module works or not is to see if itwill build: enable it in Setup, then if you get compilation or linkerrors, disable it -- you're either missing support or need to adjustthe compilation and linking parameters for that module.On SGI IRIX, there are modules that interface to many SGI specificsystem libraries, e.g. the GL library and the audio hardware.  Thesemodules will not be built by the setup.py script.In addition to the file Setup, you can also edit the file Setup.local.(the makesetup script processes both).  You may find it moreconvenient to edit Setup.local and leave Setup alone.  Then, wheninstalling a new Python version, you can copy your old Setup.localfile.Setting the optimization/debugging options------------------------------------------If you want or need to change the optimization/debugging options forthe C compiler, assign to the OPT variable on the toplevel makecommand; e.g. "make OPT=-g" will build a debugging version of Pythonon most platforms.  The default is OPT=-O; a value for OPT in theenvironment when the configure script is run overrides this default(likewise for CC; and the initial value for LIBS is used as the baseset of libraries to link with).When compiling with GCC, the default value of OPT will also includethe -Wall and -Wstrict-prototypes options.Additional debugging code to help debug memory management problems canbe enabled by using the --with-pydebug option to the configure script.For flags that change binary compatibility, use the EXTRA_CFLAGSvariable.Profiling---------If you want C profiling turned on, the easiest way is to run configurewith the CC environment variable to the necessary compilerinvocation.  For example, on Linux, this works for profiling usinggprof(1):    CC="gcc -pg" ./configureNote that on Linux, gprof apparently does not work for sharedlibraries.  The Makefile/Setup mechanism can be used to compile andlink most extension modules statically.Coverage checking-----------------For C coverage checking using gcov, run "make coverage".  This willbuild a Python binary with profiling activated, and a ".gcno" and".gcda" file for every source file compiled with that option.  Withthe built binary, now run the code whose coverage you want to check.Then, you can see coverage statistics for each individual source fileby running gcov, e.g.    gcov -o Modules zlibmoduleThis will create a "zlibmodule.c.gcov" file in the current directorycontaining coverage info for that source file.This works only for source files statically compiled into theexecutable; use the Makefile/Setup mechanism to compile and linkextension modules you want to coverage-check statically.Testing-------To test the interpreter, type "make test" in the top-level directory.This runs the test set twice (once with no compiled files, once withthe compiled files left by the previous test run).  The test setproduces some output.  You can generally ignore the messages aboutskipped tests due to optional features which can't be imported.If a message is printed about a failed test or a traceback or coredump is produced, something is wrong.  On some Linux systems (thosethat are not yet using glibc 6), test_strftime fails due to anon-standard implementation of strftime() in the C library. Pleaseignore this, or upgrade to glibc version 6.IMPORTANT: If the tests fail and you decide to mail a bug report,*don't* include the output of "make test".  It is useless.  Run thefailing test manually, as follows:        ./python ./Lib/test/test_whatever.py(substituting the top of the source tree for '.' if you built in adifferent directory).  This runs the test in verbose mode.Installing----------To install the Python binary, library modules, shared library modules(see below), include files, configuration files, and the manual page,just type        make installThis will install all platform-independent files in subdirectories ofthe directory given with the --prefix option to configure or to the`prefix' Make variable (default /usr/local).  All binary and otherplatform-specific files will be installed in subdirectories if thedirectory given by --exec-prefix or the `exec_prefix' Make variable(defaults to the --prefix directory) is given.If DESTDIR is set, it will be taken as the root directory of theinstallation, and files will be installed into $(DESTDIR)$(prefix),$(DESTDIR)$(exec_prefix), etc.All subdirectories created will have Python's version number in theirname, e.g. the library modules are installed in"/usr/local/lib/python<version>/" by default, where <version> is the<major>.<minor> release number (e.g. "2.1").  The Python binary isinstalled as "python<version>" and a hard link named "python" iscreated.  The only file not installed with a version number in itsname is the manual page, installed as "/usr/local/man/man1/python.1"by default.If you want to install multiple versions of Python see the section belowentitled "Installing multiple versions".The only thing you may have to install manually is the Python mode forEmacs found in Misc/python-mode.el.  (But then again, more recentversions of Emacs may already have it.)  Follow the instructions thatcame with Emacs for installation of site-specific files.On Mac OS X, if you have configured Python with --enable-framework, youshould use "make frameworkinstall" to do the installation. Note that thisinstalls the Python executable in a place that is not normally on yourPATH, you may want to set up a symlink in /usr/local/bin.Installing multiple versions----------------------------On Unix and Mac systems if you intend to install multiple versions of Pythonusing the same installation prefix (--prefix argument to the configurescript) you must take care that your primary python executable is notoverwritten by the installation of a different versio.  All files anddirectories installed using "make altinstall" contain the major and minorversion and can thus live side-by-side.  "make install" also creates${prefix}/bin/python which refers to ${prefix}/bin/pythonX.Y.  If you intendto install multiple versions using the same prefix you must decide whichversion (if any) is your "primary" version.  Install that version using"make install".  Install all other versions using "make altinstall".For example, if you want to install Python 2.5, 2.6 and 3.0 with 2.6 beingthe primary version, you would execute "make install" in your 2.6 builddirectory and "make altinstall" in the others.Configuration options and variables-----------------------------------Some special cases are handled by passing options to the configurescript.WARNING: if you rerun the configure script with different options, youmust run "make clean" before rebuilding.  Exceptions to this rule:after changing --prefix or --exec-prefix, all you need to do is removeModules/getpath.o.--with(out)-gcc: The configure script uses gcc (the GNU C compiler) if        it finds it.  If you don't want this, or if this compiler is        installed but broken on your platform, pass the option        --without-gcc.  You can also pass "CC=cc" (or whatever the        name of the proper C compiler is) in the environment, but the        advantage of using --without-gcc is that this option is        remembered by the config.status script for its --recheck        option.--prefix, --exec-prefix: If you want to install the binaries and the        Python library somewhere else than in /usr/local/{bin,lib},        you can pass the option --prefix=DIRECTORY; the interpreter        binary will be installed as DIRECTORY/bin/python and the        library files as DIRECTORY/lib/python/*.  If you pass        --exec-prefix=DIRECTORY (as well) this overrides the        installation prefix for architecture-dependent files (like the        interpreter binary).  Note that --prefix=DIRECTORY also        affects the default module search path (sys.path), when        Modules/config.c is compiled.  Passing make the option        prefix=DIRECTORY (and/or exec_prefix=DIRECTORY) overrides the        prefix set at configuration time; this may be more convenient        than re-running the configure script if you change your mind        about the install prefix.--with-readline: This option is no longer supported.  GNU        readline is automatically enabled by setup.py when present.--with-threads: On most Unix systems, you can now use multiple        threads, and support for this is enabled by default.  To        disable this, pass --with-threads=no.  If the library required        for threads lives in a peculiar place, you can use        --with-thread=DIRECTORY.  IMPORTANT: run "make clean" after        changing (either enabling or disabling) this option, or you        will get link errors!  Note: for DEC Unix use        --with-dec-threads instead.--with-sgi-dl: On SGI IRIX 4, dynamic loading of extension modules is        supported by the "dl" library by Jack Jansen, which is        ftp'able from ftp://ftp.cwi.nl/pub/dynload/dl-1.6.tar.Z.        This is enabled (after you've ftp'ed and compiled the dl        library) by passing --with-sgi-dl=DIRECTORY where DIRECTORY        is the absolute pathname of the dl library.  (Don't bother on        IRIX 5, it already has dynamic linking using SunOS style        shared libraries.)  THIS OPTION IS UNSUPPORTED.--with-dl-dld: Dynamic loading of modules is rumored to be supported        on some other systems: VAX (Ultrix), Sun3 (SunOS 3.4), Sequent        Symmetry (Dynix), and Atari ST.  This is done using a        combination of the GNU dynamic loading package        (ftp://ftp.cwi.nl/pub/dynload/dl-dld-1.1.tar.Z) and an        emulation of the SGI dl library mentioned above (the emulation        can be found at        ftp://ftp.cwi.nl/pub/dynload/dld-3.2.3.tar.Z).  To        enable this, ftp and compile both libraries, then call        configure, passing it the option        --with-dl-dld=DL_DIRECTORY,DLD_DIRECTORY where DL_DIRECTORY is        the absolute pathname of the dl emulation library and        DLD_DIRECTORY is the absolute pathname of the GNU dld library.        (Don't bother on SunOS 4 or 5, they already have dynamic        linking using shared libraries.)  THIS OPTION IS UNSUPPORTED.--with-libm, --with-libc: It is possible to specify alternative        versions for the Math library (default -lm) and the C library        (default the empty string) using the options        --with-libm=STRING and --with-libc=STRING, respectively.  For        example, if your system requires that you pass -lc_s to the C        compiler to use the shared C library, you can pass        --with-libc=-lc_s. These libraries are passed after all other        libraries, the C library last.--with-libs='libs': Add 'libs' to the LIBS that the python interpreter        is linked against.--with-cxx-main=<compiler>: If you plan to use C++ extension modules,        then -- on some platforms -- you need to compile python's main()        function with the C++ compiler. With this option, make will use        <compiler> to compile main() *and* to link the python executable.        It is likely that the resulting executable depends on the C++        runtime library of <compiler>. (The default is --without-cxx-main.)        There are platforms that do not require you to build Python        with a C++ compiler in order to use C++ extension modules.        E.g., x86 Linux with ELF shared binaries and GCC 3.x, 4.x is such        a platform. We recommend that you configure Python        --without-cxx-main on those platforms because a mismatch        between the C++ compiler version used to build Python and to        build a C++ extension module is likely to cause a crash at        runtime.        The Python installation also stores the variable CXX that        determines, e.g., the C++ compiler distutils calls by default        to build C++ extensions. If you set CXX on the configure command        line to any string of non-zero length, then configure won't        change CXX. If you do not preset CXX but pass        --with-cxx-main=<compiler>, then configure sets CXX=<compiler>.        In all other cases, configure looks for a C++ compiler by        some common names (c++, g++, gcc, CC, cxx, cc++, cl) and sets        CXX to the first compiler it finds. If it does not find any        C++ compiler, then it sets CXX="".        Similarly, if you want to change the command used to link the        python executable, then set LINKCC on the configure command line.--with-pydebug:  Enable additional debugging code to help track down        memory management problems.  This allows printing a list of all        live objects when the interpreter terminates.--with(out)-universal-newlines: enable reading of text files with        foreign newline convention (default: enabled). In other words,        any of \r, \n or \r\n is acceptable as end-of-line character.        If enabled import and execfile will automatically accept any newline        in files. Python code can open a file with open(file, 'U') to        read it in universal newline mode. THIS OPTION IS UNSUPPORTED.--with-tsc: Profile using the Pentium timestamping counter (TSC).--with-system-ffi:  Build the _ctypes extension module using an ffi        library installed on the system.Building for multiple architectures (using the VPATH feature)-------------------------------------------------------------If your file system is shared between multiple architectures, itusually is not necessary to make copies of the sources for eacharchitecture you want to support.  If the make program supports theVPATH feature, you can create an empty build directory for eacharchitecture, and in each directory run the configure script (on theappropriate machine with the appropriate options).  This creates thenecessary subdirectories and the Makefiles therein.  The Makefilescontain a line VPATH=... which points to a directory containing theactual sources.  (On SGI systems, use "smake -J1" instead of "make" ifyou use VPATH -- don't try gnumake.)For example, the following is all you need to build a minimal Pythonin /usr/tmp/python (assuming ~guido/src/python is the topleveldirectory and you want to build in /usr/tmp/python):        $ mkdir /usr/tmp/python        $ cd /usr/tmp/python        $ ~guido/src/python/configure        [...]        $ make        [...]        $Note that configure copies the original Setup file to the builddirectory if it finds no Setup file there.  This means that you canedit the Setup file for each architecture independently.  For thisreason, subsequent changes to the original Setup file are not trackedautomatically, as they might overwrite local changes.  To force a copyof a changed original Setup file, delete the target Setup file.  (Themakesetup script supports multiple input files, so if you want to befancy you can change the rules to create an empty Setup.local if itdoesn't exist and run it with arguments $(srcdir)/Setup Setup.local;however this assumes that you only need to add modules.)Also note that you can't use a workspace for VPATH and non VPATH builds. Theobject files left behind by one version confuses the other.Building on non-UNIX systems----------------------------For Windows (2000/NT/ME/98/95), assuming you have MS VC++ 7.1, theproject files are in PCbuild, the workspace is pcbuild.dsw.  SeePCbuild\readme.txt for detailed instructions.For other non-Unix Windows compilers, in particular MS VC++ 6.0 andfor OS/2, enter the directory "PC" and read the file "readme.txt".For the Mac, a separate source distribution will be made available,for use with the CodeWarrior compiler.  If you are interested in Macdevelopment, join the PythonMac Special Interest Group(http://www.python.org/sigs/pythonmac-sig/, or send email topythonmac-sig-request@python.org).Of course, there are also binary distributions available for theseplatforms -- seehttp://www.python.org/.To port Python to a new non-UNIX system, you will have to fake theeffect of running the configure script manually (for Mac and PC, thishas already been done for you).  A good start is to copy the filepyconfig.h.in to pyconfig.h and edit the latter to reflect the actualconfiguration of your system.  Most symbols must simply be defined as1 only if the corresponding feature is present and can be left aloneotherwise; however the *_t type symbols must be defined as somevariant of int if they need to be defined at all.For all platforms, it's important that the build arrange to define thepreprocessor symbol NDEBUG on the compiler command line in a releasebuild of Python (else assert() calls remain in the code, hurtingrelease-build performance).  The Unix, Windows and Mac builds alreadydo this.Miscellaneous issues====================Emacs mode----------There's an excellent Emacs editing mode for Python code; see the fileMisc/python-mode.el.  Originally written by the famous Tim Peters, itis now maintained by the equally famous Barry Warsaw (it's nocoincidence that they now both work on the same team).  The latestversion, along with various other contributed Python-related Emacsgoodies, is online athttp://www.python.org/emacs/python-mode.  Andif you are planning to edit the Python C code, please pick up thelatest version of CC Modehttp://www.python.org/emacs/cc-mode; itcontains a "python" style used throughout most of the Python C sourcefiles.  (Newer versions of Emacs or XEmacs may already come with thelatest version of python-mode.)Tkinter-------The setup.py script automatically configures this when it detects ausable Tcl/Tk installation.  This requires Tcl/Tk version 8.0 orhigher.For more Tkinter information, see the Tkinter Resource page:http://www.python.org/topics/tkinter/There are demos in the Demo/tkinter directory.Note that there's a Python module called "Tkinter" (capital T) whichlives in Lib/lib-tk/Tkinter.py, and a C module called "_tkinter"(lower case t and leading underscore) which lives inModules/_tkinter.c.  Demos and normal Tk applications import only thePython Tkinter module -- only the latter imports the C _tkintermodule.  In order to find the C _tkinter module, it must be compiledand linked into the Python interpreter -- the setup.py script doesthis.  In order to find the Python Tkinter module, sys.path must beset correctly -- normal installation takes care of this.Distribution structure----------------------Most subdirectories have their own README files.  Most files havecomments.Demo/           Demonstration scripts, modules and programsDoc/            Documentation sources (reStructuredText)Grammar/        Input for the parser generatorInclude/        Public header filesLICENSE         Licensing informationLib/            Python library modulesMac/            Macintosh specific resourcesMakefile.pre.in Source from which config.status creates the Makefile.preMisc/           Miscellaneous useful filesModules/        Implementation of most built-in modulesObjects/        Implementation of most built-in object typesPC/             Files specific to PC ports (DOS, Windows, OS/2)PCbuild/        Build directory for Microsoft Visual C++Parser/         The parser and tokenizer and their input handlingPython/         The byte-compiler and interpreterREADME          The file you're reading nowRISCOS/         Files specific to RISC OS portTools/          Some useful programs written in Pythonpyconfig.h.in   Source from which pyconfig.h is created (GNU autoheader output)configure       Configuration shell script (GNU autoconf output)configure.in    Configuration specification (input for GNU autoconf)install-sh      Shell script used to install filessetup.py        Python script used to build extension modulesThe following files will (may) be created in the toplevel directory bythe configuration and build processes:Makefile        Build rulesMakefile.pre    Build rules before running Modules/makesetupbuildno         Keeps track of the build numberconfig.cache    Cache of configuration variablespyconfig.h      Configuration headerconfig.log      Log from last configure runconfig.status   Status from last run of the configure scriptgetbuildinfo.o  Object file from Modules/getbuildinfo.clibpython<version>.a    The library archivepython          The executable interpreterreflog.txt      Output from running the regression suite with the -R flag tags, TAGS      Tags files for vi and EmacsThat's all, folks!--------------------Guido van Rossum (home page:http://www.python.org/~guido/)