This is Python version 2.3 (pre-alpha)

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

Copyright (c) 2001, 2002 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,

especially the part on customizing Modules/Setup.

What is Python anyway?

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

Python is an interpreted 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://www.python.org/doc/ 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://www.python.org/psa/bookstore/ 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://www.python.org/doc/, 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.

The best documentation for the new (in Python 2.2) type/class

unification features is Guido's tutorial introduction, at

http://www.python.org/2.2/descrintro.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/psa/MailingLists.html for an

overview of the many 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/psa/MailingLists.html for details.

Bug reports

-----------

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

Tracker at http://sourceforge.net/bugs/?group_id=5470.

Patches and contributions

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

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

Manager at http://sourceforge.net/patch/?group_id=5470. Guidelines

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

http://python.sourceforge.net/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 [email protected] (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 section 3 of the FAQ

(http://www.python.org/cgi-bin/faqw.py or

http://www.python.org/doc/FAQ.html) 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. When you fix a

configure problem, be sure to remove config.cache!

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

egcs, and some vendor-supplied compilers, which can sometimes be

worked around by turning off optimization. Consider switching to

stable versions (gcc 2.7.2.3, egcs 1.1.2, 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, egcs).

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!)

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).

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.

Under Linux systems using GNU libc 2 (aka libc6), the crypt

module now needs the -lcrypt option. The setup.py script

takes care of this automatically.

Red Hat Linux: There's an executable /usr/bin/python which is Python

1.5.2 on most 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).

HP-UX: Please read the file Misc/HPUX-NOTES for shared libraries.

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 config.h defines it.

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.

Minix: When using ack, use "CC=cc AR=aal RANLIB=: ./configure"!

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.

SunOS 4.x: When using the SunPro C compiler, you may want to use the

'-Xa' option instead of '-Xc', to enable some needed non-ANSI

Sunisms.

NeXT: Not supported anymore. Start with the MacOSX/Darwin code if you

want to revive it.

QNX: Chris Herborth ([email protected]) 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: Chris Herborth ([email protected]) writes:

See BeOS/README 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: Konrad Hinsen writes:

1) Don't use gcc. It compiles Python/graminit.c into something

that the Cray assembler doesn't like. Cray's cc seems to work

fine.

2) Comment out modules md5 (won't compile) and audioop (will

crash the interpreter during the test suite).

If you run the test suite, two tests will fail (rotate and

binascii), but these are not the modules you'd expect to need

on a Cray.

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.

Mac OS X 10: One of the regular expression tests fails with a segmentation

violation (SIGSEGV) due to the small stack size used by default,

if you give the command "limit stacksize 2048" before "make test"

it should work.

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. Alternatively, do "sudo make install"

which installs everything as superuser.

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). You may also want to check out ./Mac/OSX

for building a Python.app. You may also want to manually

install a symlink in /usr/local/bin/python to the executable

deep down in the framework.

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!

Configuring the bsddb and dbm modules

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

Configuring the bsddb module can sometimes be a bit tricky. This module

provides a Python interface to the Berkeley DB library. As of this writing

several versions of the underlying library are in common use (versions 1.85,

2.x, 3.x, and 4.x). The file formats across the various versions tend to be

incompatible. Some Linux distributions install multiple versions by

default. It is important that compatible versions of header files and

libraries are used when building bsddb. To make matters worse, version 1.85

of Berkeley DB has known bugs in its hash file implementation, but is still

the most widely available version of the library. Many people build bsddb

with version 1.85 but aren't aware of the bugs. This affects people using

the anydbm and dbhash modules because they are both use Berkeley DB's hash

file format as a side effect of calling bsddb.hashopen.

To try and remedy this problem, beginning with Python version 2.3 a number

of changes to the bsddb build process were made. First, and most important,

the bsddb module will not be built with version 1.85 unless the relevant

lines in setup.py are uncommented first and no other higher-numbered

versions are found. Second, matching versions of the library and include

files must be found. Third, searching is performed in order, starting from

version 4 and proceeding to version 2 (or version 1 if it is enabled).

Version-independent libraries and header files (e.g. /usr/lib/libdb.a and

/usr/include/db.h) are never considered. They must be in version-specific

directories or have version-specific filenames (e.g. /usr/lib/libdb-3.2.so

and /usr/include/db3/db_185.h).

Since the bsddb module is programmed using the Berkeley DB version 1 API,

the underlying library must be configured with the --enable-compat185 flag.

Most vendor-provided distributions are so-configured. This is generally

only an issue if you build Berkeley DB from source.

All this affects the dbm module as well. There are several dbm-compliant

APIs provided by different libraries, including ndbm, gdbm and Berkeley DB.

The build process for dbm would previously use the version 1.85 library,

thus extending the potential hash file corruption to the dbm module as well.

The dbm module will use the library and include files found for the bsddb

module if neither ndbm nor gdbm libraries are found.

Configuring threads

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

As of Python 2.0, threads are enabled by default. If you wish to

compile without threads, or if your thread support is broken, pass the

--with-threads=no switch to configure. Unfortunately, on some

platforms, additional compiler and/or linker options are required for

threads to work properly. Below is a table of those options,

collected by Bill Janssen. We would love to automate this process

more, but the information below is not enough to write a patch for the

configure.in file, so manual intervention is required. If you patch

the configure.in file and are confident that the patch works, please

send in the patch. (Don't bother patching the configure script itself

-- it is regenerated each the configure.in file changes.)

Compiler switches for threads

.............................

The definition of _REENTRANT should be configured automatically, if

that does not work on your system, or if _REENTRANT is defined

incorrectly, 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

([email protected])

Digital UNIX 4.x/cc/DCE -threads

([email protected])

Digital UNIX 4.x/cc/POSIX -pthread

([email protected])

AIX 4.1.4/cc_r/d7 (nothing)

([email protected])

AIX 4.1.4/cc_r4/DCE (nothing)

([email protected])

IRIX 6.2/cc/POSIX (nothing)

([email protected])

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

([email protected])

Digital UNIX 4.x/DCE -lpthreads -lpthread -lmach -lexc -lc

([email protected])

Digital UNIX 4.x/POSIX -lpthread -lmach -lexc -lc

([email protected])

AIX 4.1.4/{draft7,DCE} (nothing)

([email protected])

IRIX 6.2/POSIX -lpthread

([email protected])

Building a shared libpython

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

Starting with Python 2.3, the majority of the interpreter can be built

into a shared library, which can then be used by the interpreter

executable, and by applications embedding Python. To enable this feature,

configure with --enable-shared.

Configuring additional built-in modules

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

Starting with Python 2.1, the setup.py script at the top of the source

distribution attempts to detect which modules can be built and

automatically compiles them. Autodetection doesn't always work, so

you can still customize the configuration by editing the Modules/Setup

file; but this should be considered a last resort. The rest of this

section only applies if you decide to edit the Modules/Setup file.

You also need this to enable static linking of certain modules (which

is 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.dist

yourself (configure will never overwrite it). Never edit Setup.dist

-- always edit Setup or Setup.local (see below). Read the comments in

the file for information on what kind of edits are allowed. When you

have edited Setup in the Modules directory, the interpreter will

automatically be rebuilt the next time you run make (in the toplevel

directory).

Many useful modules can be built on any Unix system, but some optional

modules can't be reliably autodetected. Often the quickest way to

determine whether a particular module works or not is to see if it

will build: enable it in Setup, then if you get compilation or link

errors, disable it -- you're either missing support or need to adjust

the compilation and linking parameters for that module.

On SGI IRIX, there are modules that interface to many SGI specific

system libraries, e.g. the GL library and the audio hardware. These

modules 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 more

convenient to edit Setup.local and leave Setup alone. Then, when

installing a new Python version, you can copy your old Setup.local

file.

Setting the optimization/debugging options

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

If you want or need to change the optimization/debugging options for

the C compiler, assign to the OPT variable on the toplevel make

command; e.g. "make OPT=-g" will build a debugging version of Python

on most platforms. The default is OPT=-O; a value for OPT in the

environment when the configure script is run overrides this default

(likewise for CC; and the initial value for LIBS is used as the base

set of libraries to link with).

When compiling with GCC, the default value of OPT will also include

the -Wall and -Wstrict-prototypes options.

Additional debugging code to help debug memory management problems can

be enabled by using the --with-pydebug option to the configure script.

Profiling

---------

If you want C profiling turned on, the easiest way is to run configure

with the CC environment variable to the necessary compiler

invocation. For example, on Linux, this works for profiling using

gprof(1):

CC="gcc -pg" ./configure

Note that on Linux, gprof apparently does not work for shared

libraries. The Makefile/Setup mechanism can be used to compile and

link most extension module 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 with

the compiled files left by the previous test run). The test set

produces some output. You can generally ignore the messages about

skipped tests due to optional features which can't be imported.

If a message is printed about a failed test or a traceback or core

dump is produced, something is wrong. On some Linux systems (those

that are not yet using glibc 6), test_strftime fails due to a

non-standard implementation of strftime() in the C library. Please

ignore 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 the

failing test manually, as follows:

./python ./Lib/test/test_whatever.py

(substituting the top of the source tree for '.' if you built in a

different 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 install

This will install all platform-independent files in subdirectories of

the directory given with the --prefix option to configure or to the

`prefix' Make variable (default /usr/local). All binary and other

platform-specific files will be installed in subdirectories if the

directory given by --exec-prefix or the `exec_prefix' Make variable

(defaults to the --prefix directory) is given.

All subdirectories created will have Python's version number in their

name, 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 is

installed as "python<version>" and a hard link named "python" is

created. The only file not installed with a version number in its

name is the manual page, installed as "/usr/local/man/man1/python.1"

by default.

If you have a previous installation of Python that you don't

want to replace yet, use

make altinstall

This installs the same set of files as "make install" except it

doesn't create the hard link to "python<version>" named "python" and

it doesn't install the manual page at all.

Alpha/beta revision levels are stripped from the executable and

library filenames during installation. For example, Python2.1a2 will

install as python2.1, overwriting the previous python2.1. To avoid

this, you could set the Makefile VERSION variable manually

(e.g. VERSION=2.1a2) before running "make install" or "make altinstall".

The only thing you may have to install manually is the Python mode for

Emacs found in Misc/python-mode.el. (But then again, more recent

versions of Emacs may already have it.) Follow the instructions that

came with Emacs for installation of site-specific files.

On Mac OS X, if you have configured Python with --enable-framework, you

should use "make frameworkinstall" to do the installation. Note that this

installs the Python executable in a place that is not normally on your

PATH, you may want to set up a symlink in /usr/local/bin.

Configuration options and variables

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

Some special cases are handled by passing options to the configure

script.

WARNING: if you rerun the configure script with different options, you

must run "make clean" before rebuilding. Exceptions to this rule:

after changing --prefix or --exec-prefix, all you need to do is remove

Modules/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.) Support for this feature is deprecated.

--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.) Support for this feature is

deprecated.

--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=<compiler>: Some C++ compilers require that main() is

compiled with the C++ if there is any C++ code in the application.

Specifically, g++ on a.out systems may require that to support

construction of global objects. With this option, the main() function

of Python will be compiled with <compiler>; use that only if you

plan to use C++ extension modules, and if your compiler requires

compilation of main() as a C++ program.

--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.

Building for multiple architectures (using the VPATH feature)

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

If your file system is shared between multiple architectures, it

usually is not necessary to make copies of the sources for each

architecture you want to support. If the make program supports the

VPATH feature, you can create an empty build directory for each

architecture, and in each directory run the configure script (on the

appropriate machine with the appropriate options). This creates the

necessary subdirectories and the Makefiles therein. The Makefiles

contain a line VPATH=... which points to a directory containing the

actual sources. (On SGI systems, use "smake -J1" instead of "make" if

you use VPATH -- don't try gnumake.)

For example, the following is all you need to build a minimal Python

in /usr/tmp/python (assuming ~guido/src/python is the toplevel

directory 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 build

directory if it finds no Setup file there. This means that you can

edit the Setup file for each architecture independently. For this

reason, subsequent changes to the original Setup file are not tracked

automatically, as they might overwrite local changes. To force a copy

of a changed original Setup file, delete the target Setup file. (The

makesetup script supports multiple input files, so if you want to be

fancy you can change the rules to create an empty Setup.local if it

doesn't exist and run it with arguments $(srcdir)/Setup Setup.local;

however this assumes that you only need to add modules.)

Building on non-UNIX systems

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

For Windows (2000/NT/ME/98/95), assuming you have MS VC++ 6.0, the

project files are in PCbuild, the workspace is pcbuild.dsw. See

PCbuild\readme.txt for detailed instructions.

For other non-Unix Windows compilers, in particular Windows 3.1 and

for 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 Mac

development, join the PythonMac Special Interest Group

(http://www.python.org/sigs/pythonmac-sig/, or send email to

[email protected]).

Of course, there are also binary distributions available for these

platforms -- see http://www.python.org/.

To port Python to a new non-UNIX system, you will have to fake the

effect of running the configure script manually (for Mac and PC, this

has already been done for you). A good start is to copy the file

pyconfig.h.in to pyconfig.h and edit the latter to reflect the actual

configuration of your system. Most symbols must simply be defined as

1 only if the corresponding feature is present and can be left alone

otherwise; however the *_t type symbols must be defined as some

variant of int if they need to be defined at all.

For all platforms, it's important that the build arrange to define the

preprocessor symbol NDEBUG on the compiler command line in a release

build of Python (else assert() calls remain in the code, hurting

release-build performance). The Unix, Windows and Mac builds already

do this.

Miscellaneous issues

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

Emacs mode

----------

There's an excellent Emacs editing mode for Python code; see the file

Misc/python-mode.el. Originally written by the famous Tim Peters, it

is now maintained by the equally famous Barry Warsaw (it's no

coincidence that they now both work on the same team). The latest

version, along with various other contributed Python-related Emacs

goodies, is online at http://www.python.org/emacs/python-mode. And

if you are planning to edit the Python C code, please pick up the

latest version of CC Mode http://www.python.org/emacs/cc-mode; it

contains a "python" style used throughout most of the Python C source

files. (Newer versions of Emacs or XEmacs may already come with the

latest version of python-mode.)

Tkinter

-------

The setup.py script automatically configures this when it detects a

usable Tcl/Tk installation. This requires Tcl/Tk version 8.0 or

higher.

For more Tkinter information, see the Tkinter Resource page:

http://www.python.org/topics/tkinter/

There are demos in the Demo/tkinter directory, in the subdirectories

guido, matt and www (the matt and guido subdirectories have been

overhauled to use more recent Tkinter coding conventions).

Note that there's a Python module called "Tkinter" (capital T) which

lives in Lib/lib-tk/Tkinter.py, and a C module called "_tkinter"

(lower case t and leading underscore) which lives in

Modules/_tkinter.c. Demos and normal Tk applications import only the

Python Tkinter module -- only the latter imports the C _tkinter

module. In order to find the C _tkinter module, it must be compiled

and linked into the Python interpreter -- the setup.py script does

this. In order to find the Python Tkinter module, sys.path must be

set correctly -- normal installation takes care of this.

Distribution structure

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

Most subdirectories have their own README files. Most files have

comments.

.cvsignore Additional filename matching patterns for CVS to ignore

BeOS/ Files specific to the BeOS port

Demo/ Demonstration scripts, modules and programs

Doc/ Documentation sources (LaTeX)

Grammar/ Input for the parser generator

Include/ Public header files

LICENSE Licensing information

Lib/ Python library modules

Mac/ Macintosh specific resources