This is Python version 2.5.2

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

Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Python 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 this

software, terms & conditions for usage, and a DISCLAIMER OF ALL

WARRANTIES.

This Python distribution contains no GNU General Public Licensed

(GPLed) code so it may be used in proprietary projects just like prior

Python distributions.  There are interfaces to some GNU code but these

are entirely optional.

All trademarks referenced herein are property of their respective

holders.

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 the

current directory and when it finishes, type "make".  This creates an

executable "./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 programming

language suitable (amongst other uses) for distributed application

development, scripting, numeric computing and system testing.  Python

is often compared to Tcl, Perl, Java, JavaScript, Visual Basic or

Scheme.  To find out more about what Python can do for you, point your

browser to http://www.python.org/.

How do I learn Python?

----------------------

The official tutorial is still a good place to start; see

http://docs.python.org/ for online and downloadable versions, as well

as a list of other introductions, and reference documentation.

There's a quickly growing set of books on Python.  See

http://wiki.python.org/moin/PythonBooks for a list.

Documentation

-------------

All documentation is provided online in a variety of formats.  In

order of importance for new users: Tutorial, Library Reference,

Language Reference, Extending & Embedding, and the Python/C API.  The

Library Reference is especially of immense value since much of

Python's power is described there, including the built-in data types

and functions!

All documentation is also available online at the Python web site

(http://docs.python.org/, see below).  It is available online for

occasional reference, or can be downloaded in many formats for faster

access.  The documentation is available in HTML, PostScript, PDF, and

LaTeX formats; the LaTeX version is primarily for documentation

authors, translators, and people with special formatting requirements.

Unfortunately, new-style classes (new in Python 2.2) have not yet been

integrated into Python's standard documentation.  A collection of

pointers to what has been written is at:

    http://www.python.org/doc/newstyle.html

Web sites

---------

New Python releases and related technologies are published at

http://www.python.org/.  Come visit us!

There's also a Python community web site at

http://starship.python.net/.

Newsgroups and Mailing Lists

----------------------------

Read comp.lang.python, a high-volume discussion newsgroup about

Python, or comp.lang.python.announce, a low-volume moderated newsgroup

for Python-related announcements.  These are also accessible as

mailing lists: see http://www.python.org/community/lists.html for an

overview of these and many other Python-related mailing lists.

Archives are accessible via the Google Groups Usenet archive; see

http://groups.google.com/.  The mailing lists are also archived, see

http://www.python.org/community/lists.html for details.

Bug reports

-----------

To report or search for bugs, please use the Python Bug

Tracker at http://bugs.python.org.

Patches and contributions

-------------------------

To submit a patch or other contribution, please use the Python Patch

Manager at http://bugs.python.org.  Guidelines

for patch submission may be found at http://www.python.org/dev/patches/.

If you have a proposal to change Python, it's best to submit a Python

Enhancement Proposal (PEP) first.  All current PEPs, as well as

guidelines for submitting a new PEP, are listed at

http://www.python.org/dev/peps/.

Questions

---------

For help, if you can't find it in the manuals or on the web site, it's

best to post to the comp.lang.python or the Python mailing list (see

above).  If you specifically don't want to involve the newsgroup or

mailing list, send questions to help@python.org (a group of volunteers

who answer questions as they can).  The newsgroup is the most

efficient 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 automated

for Unix and Linux installations, so all you usually have to do is

type a few commands and sit back.  There are some platforms where

things are not quite as smooth; see the platform specific notes below.

If you want to build for multiple platforms sharing the same source

tree, see the section on VPATH below.

Start by running the script "./configure", which determines your

system configuration and creates the Makefile.  (It takes a minute or

two -- please be patient!)  You may want to pass options to the

configure script -- see the section below on configuration options and

variables.  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 be

rebuilt.  In this case you may have to run make again to correctly

build your desired target.  The interpreter executable is built in the

top level directory.

Once you have built a Python interpreter, see the subsections below on

testing and installation.  If you run into trouble, see the next

section.

Previous versions of Python used a manual configuration process that

involved editing the file Modules/Setup.  While this file still exists

and manual configuration is still supported, it is rarely needed any

more: almost all modules are automatically built as appropriate under

guidance of the setup.py script, which is run by Make after the

interpreter 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, and

how to fix it.

If you rerun the configure script with different options, remove all

object files by running "make clean" before rebuilding.  Believe it or

not, "make clean" sometimes helps to clean up other inexplicable

problems as well.  Try it before sending in a bug report!

If the configure script fails or doesn't seem to find things that

should be there, inspect the config.log file.

If you get a warning for every file about the -Olimit option being no

longer supported, you can ignore it.  There's no foolproof way to know

whether this option is needed; all we can do is test whether it is

accepted without error.  On some systems, e.g. older SGI compilers, it

is essential for performance (specifically when compiling ceval.c,

which has more basic blocks than the default limit of 1000).  If the

warning bothers you, edit the Makefile to remove "-Olimit 1500" from

the OPT variable.

If you get failures in test_long, or sys.maxint gets set to -1, you

are probably experiencing compiler bugs, usually related to

optimization.  This is a common problem with some versions of gcc, and

some vendor-supplied compilers, which can sometimes be worked around

by 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 using

old K&R-C-only compilers is no longer possible.  ANSI C compilers are

available for all modern systems, either in the form of updated

compilers 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 PYTHONHOME

environment variables set, as they may interfere with the newly built

executable which is compiling the library.

Unsupported systems

-------------------

A number of features are not supported in Python 2.5 anymore. Some

support 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 you

volunteer to support this system. For a more detailed discussion 

regarding no-longer-supported and resupporting platforms, as well

as a list of platforms that became or will be unsupported, see PEP 11.

More specifically, the following systems are not supported any

longer:

- 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 9

The following systems are still supported in Python 2.5, but

support will be dropped in 2.6:

- Systems using --with-wctype-functions

- Win9x, WinME

Warning on install in Windows 98 and Windows Me

-----------------------------------------------

Following Microsoft's closing of Extended Support for

Windows 98/ME (July 11, 2006), Python 2.6 will stop

supporting these platforms. Python development and

maintainability becomes easier (and more reliable) when

platform specific code targeting OSes with few users

and no dedicated expert developers is taken out. The

vendor also warns that the OS versions listed above

"can expose customers to security risks" and recommends

upgrade.

Platform specific notes

-----------------------

(Some of these may no longer apply.  If you find you can build Python

on these platforms without the special directions mentioned here,

submit a documentation bug report to SourceForge (see Bug Reports

above) 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, imageop and rgbimg 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"

        make

HP-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

        (see http://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, rgbimg, rotor,

                select, signal, socket, soundex, strop, struct,

                syslog, termios, time, timing, zlib, audioop, imageop, rgbimg

        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 48k

BeOS:   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