1 This is Python version 2.6 alpha 0
2 ==================================
4 Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006 Python Software Foundation.
7 Copyright (c) 2000 BeOpen.com.
10 Copyright (c) 1995-2001 Corporation for National Research Initiatives.
13 Copyright (c) 1991-1995 Stichting Mathematisch Centrum.
20 See the file "LICENSE" for information on the history of this
21 software, terms & conditions for usage, and a DISCLAIMER OF ALL
24 This Python distribution contains no GNU General Public Licensed
25 (GPLed) code so it may be used in proprietary projects just like prior
26 Python distributions. There are interfaces to some GNU code but these
27 are entirely optional.
29 All trademarks referenced herein are property of their respective
33 What's new in this release?
34 ---------------------------
36 See the file "Misc/NEWS".
39 If you don't read instructions
40 ------------------------------
42 Congratulations on getting this far. :-)
44 To start building right away (on UNIX): type "./configure" in the
45 current directory and when it finishes, type "make". This creates an
46 executable "./python"; to install in /usr/local, first do "su root"
47 and then "make install".
49 The section `Build instructions' below is still recommended reading.
52 What is Python anyway?
53 ----------------------
55 Python is an interpreted, interactive object-oriented programming
56 language suitable (amongst other uses) for distributed application
57 development, scripting, numeric computing and system testing. Python
58 is often compared to Tcl, Perl, Java, JavaScript, Visual Basic or
59 Scheme. To find out more about what Python can do for you, point your
60 browser to http://www.python.org/.
63 How do I learn Python?
64 ----------------------
66 The official tutorial is still a good place to start; see
67 http://docs.python.org/ for online and downloadable versions, as well
68 as a list of other introductions, and reference documentation.
70 There's a quickly growing set of books on Python. See
71 http://wiki.python.org/moin/PythonBooks for a list.
77 All documentation is provided online in a variety of formats. In
78 order of importance for new users: Tutorial, Library Reference,
79 Language Reference, Extending & Embedding, and the Python/C API. The
80 Library Reference is especially of immense value since much of
81 Python's power is described there, including the built-in data types
84 All documentation is also available online at the Python web site
85 (http://docs.python.org/, see below). It is available online for
86 occasional reference, or can be downloaded in many formats for faster
87 access. The documentation is available in HTML, PostScript, PDF, and
88 LaTeX formats; the LaTeX version is primarily for documentation
89 authors, translators, and people with special formatting requirements.
91 Unfortunately, new-style classes (new in Python 2.2) have not yet been
92 integrated into Python's standard documentation. A collection of
93 pointers to what has been written is at:
95 http://www.python.org/doc/newstyle.html
101 New Python releases and related technologies are published at
102 http://www.python.org/. Come visit us!
104 There's also a Python community web site at
105 http://starship.python.net/.
108 Newsgroups and Mailing Lists
109 ----------------------------
111 Read comp.lang.python, a high-volume discussion newsgroup about
112 Python, or comp.lang.python.announce, a low-volume moderated newsgroup
113 for Python-related announcements. These are also accessible as
114 mailing lists: see http://www.python.org/community/lists.html for an
115 overview of these and many other Python-related mailing lists.
117 Archives are accessible via the Google Groups Usenet archive; see
118 http://groups.google.com/. The mailing lists are also archived, see
119 http://www.python.org/community/lists.html for details.
125 To report or search for bugs, please use the Python Bug
126 Tracker at http://sourceforge.net/bugs/?group_id=5470.
129 Patches and contributions
130 -------------------------
132 To submit a patch or other contribution, please use the Python Patch
133 Manager at http://sourceforge.net/patch/?group_id=5470. Guidelines
134 for patch submission may be found at http://www.python.org/patches/.
136 If you have a proposal to change Python, it's best to submit a Python
137 Enhancement Proposal (PEP) first. All current PEPs, as well as
138 guidelines for submitting a new PEP, are listed at
139 http://www.python.org/peps/.
145 For help, if you can't find it in the manuals or on the web site, it's
146 best to post to the comp.lang.python or the Python mailing list (see
147 above). If you specifically don't want to involve the newsgroup or
148 mailing list, send questions to help@python.org (a group of volunteers
149 who answer questions as they can). The newsgroup is the most
150 efficient way to ask public questions.
156 Before you can build Python, you must first configure it.
157 Fortunately, the configuration and build process has been automated
158 for Unix and Linux installations, so all you usually have to do is
159 type a few commands and sit back. There are some platforms where
160 things are not quite as smooth; see the platform specific notes below.
161 If you want to build for multiple platforms sharing the same source
162 tree, see the section on VPATH below.
164 Start by running the script "./configure", which determines your
165 system configuration and creates the Makefile. (It takes a minute or
166 two -- please be patient!) You may want to pass options to the
167 configure script -- see the section below on configuration options and
168 variables. When it's done, you are ready to run make.
170 To build Python, you normally type "make" in the toplevel directory.
171 If you have changed the configuration, the Makefile may have to be
172 rebuilt. In this case you may have to run make again to correctly
173 build your desired target. The interpreter executable is built in the
176 Once you have built a Python interpreter, see the subsections below on
177 testing and installation. If you run into trouble, see the next
180 Previous versions of Python used a manual configuration process that
181 involved editing the file Modules/Setup. While this file still exists
182 and manual configuration is still supported, it is rarely needed any
183 more: almost all modules are automatically built as appropriate under
184 guidance of the setup.py script, which is run by Make after the
185 interpreter has been built.
191 See also the platform specific notes in the next section.
193 If you run into other trouble, see the FAQ
194 (http://www.python.org/doc/faq) for hints on what can go wrong, and
197 If you rerun the configure script with different options, remove all
198 object files by running "make clean" before rebuilding. Believe it or
199 not, "make clean" sometimes helps to clean up other inexplicable
200 problems as well. Try it before sending in a bug report!
202 If the configure script fails or doesn't seem to find things that
203 should be there, inspect the config.log file.
205 If you get a warning for every file about the -Olimit option being no
206 longer supported, you can ignore it. There's no foolproof way to know
207 whether this option is needed; all we can do is test whether it is
208 accepted without error. On some systems, e.g. older SGI compilers, it
209 is essential for performance (specifically when compiling ceval.c,
210 which has more basic blocks than the default limit of 1000). If the
211 warning bothers you, edit the Makefile to remove "-Olimit 1500" from
214 If you get failures in test_long, or sys.maxint gets set to -1, you
215 are probably experiencing compiler bugs, usually related to
216 optimization. This is a common problem with some versions of gcc, and
217 some vendor-supplied compilers, which can sometimes be worked around
218 by turning off optimization. Consider switching to stable versions
219 (gcc 2.95.2, gcc 3.x, or contact your vendor.)
221 From Python 2.0 onward, all Python C code is ANSI C. Compiling using
222 old K&R-C-only compilers is no longer possible. ANSI C compilers are
223 available for all modern systems, either in the form of updated
224 compilers from the vendor, or one of the free compilers (gcc).
226 If "make install" fails mysteriously during the "compiling the library"
227 step, make sure that you don't have any of the PYTHONPATH or PYTHONHOME
228 environment variables set, as they may interfere with the newly built
229 executable which is compiling the library.
234 A number of features are not supported in Python 2.5 anymore. Some
235 support code is still present, but will be removed in Python 2.6.
236 If you still need to use current Python versions on these systems,
237 please send a message to python-dev@python.org indicating that you
238 volunteer to support this system. For a more detailed discussion
239 regarding no-longer-supported and resupporting platforms, as well
240 as a list of platforms that became or will be unsupported, see PEP 11.
242 More specifically, the following systems are not supported any
249 - Irix 4 and --with-sgi-dl
251 - Systems defining __d6_pthread_create (configure.in)
252 - Systems defining PY_PTHREAD_D4, PY_PTHREAD_D6,
253 or PY_PTHREAD_D7 in thread_pthread.h
254 - Systems using --with-dl-dld
255 - Systems using --without-universal-newlines
258 The following systems are still supported in Python 2.5, but
259 support will be dropped in 2.6:
260 - Systems using --with-wctype-functions
263 Warning on install in Windows 98 and Windows Me
264 -----------------------------------------------
266 Following Microsoft's closing of Extended Support for
267 Windows 98/ME (July 11, 2006), Python 2.6 will stop
268 supporting these platforms. Python development and
269 maintainability becomes easier (and more reliable) when
270 platform specific code targeting OSes with few users
271 and no dedicated expert developers is taken out. The
272 vendor also warns that the OS versions listed above
273 "can expose customers to security risks" and recommends
276 Platform specific notes
277 -----------------------
279 (Some of these may no longer apply. If you find you can build Python
280 on these platforms without the special directions mentioned here,
281 submit a documentation bug report to SourceForge (see Bug Reports
282 above) so we can remove them!)
284 Unix platforms: If your vendor still ships (and you still use) Berkeley DB
285 1.85 you will need to edit Modules/Setup to build the bsddb185
286 module and add a line to sitecustomize.py which makes it the
287 default. In Modules/Setup a line like
289 bsddb185 bsddbmodule.c
291 should work. (You may need to add -I, -L or -l flags to direct the
292 compiler and linker to your include files and libraries.)
294 XXX I think this next bit is out of date:
296 64-bit platforms: The modules audioop, imageop and rgbimg don't work.
297 The setup.py script disables them on 64-bit installations.
298 Don't try to enable them in the Modules/Setup file. They
299 contain code that is quite wordsize sensitive. (If you have a
302 Solaris: When using Sun's C compiler with threads, at least on Solaris
303 2.5.1, you need to add the "-mt" compiler option (the simplest
304 way is probably to specify the compiler with this option as
305 the "CC" environment variable when running the configure
308 When using GCC on Solaris, beware of binutils 2.13 or GCC
309 versions built using it. This mistakenly enables the
310 -zcombreloc option which creates broken shared libraries on
311 Solaris. binutils 2.12 works, and the binutils maintainers
312 are aware of the problem. Binutils 2.13.1 only partially
313 fixed things. It appears that 2.13.2 solves the problem
314 completely. This problem is known to occur with Solaris 2.7
315 and 2.8, but may also affect earlier and later versions of the
318 When the dynamic loader complains about errors finding shared
321 ld.so.1: ./python: fatal: libstdc++.so.5: open failed:
322 No such file or directory
324 you need to first make sure that the library is available on
325 your system. Then, you need to instruct the dynamic loader how
326 to find it. You can choose any of the following strategies:
328 1. When compiling Python, set LD_RUN_PATH to the directories
329 containing missing libraries.
330 2. When running Python, set LD_LIBRARY_PATH to these directories.
331 3. Use crle(8) to extend the search path of the loader.
332 4. Modify the installed GCC specs file, adding -R options into the
335 The complex object fails to compile on Solaris 10 with gcc 3.4 (at
336 least up to 3.4.3). To work around it, define Py_HUGE_VAL as
339 make CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()" -I. -I$(srcdir)/Include'
340 ./python setup.py CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()"'
342 Linux: A problem with threads and fork() was tracked down to a bug in
343 the pthreads code in glibc version 2.0.5; glibc version 2.0.7
344 solves the problem. This causes the popen2 test to fail;
345 problem and solution reported by Pablo Bleyer.
347 Red Hat Linux: Red Hat 9 built Python2.2 in UCS-4 mode and hacked
348 Tcl to support it. To compile Python2.3 with Tkinter, you will
349 need to pass --enable-unicode=ucs4 flag to ./configure.
351 There's an executable /usr/bin/python which is Python
352 1.5.2 on most older Red Hat installations; several key Red Hat tools
353 require this version. Python 2.1.x may be installed as
354 /usr/bin/python2. The Makefile installs Python as
355 /usr/local/bin/python, which may or may not take precedence
356 over /usr/bin/python, depending on how you have set up $PATH.
358 FreeBSD 3.x and probably platforms with NCurses that use libmytinfo or
359 similar: When using cursesmodule, the linking is not done in
360 the correct order with the defaults. Remove "-ltermcap" from
361 the readline entry in Setup, and use as curses entry: "curses
362 cursesmodule.c -lmytinfo -lncurses -ltermcap" - "mytinfo" (so
363 called on FreeBSD) should be the name of the auxiliary library
364 required on your platform. Normally, it would be linked
365 automatically, but not necessarily in the correct order.
367 BSDI: BSDI versions before 4.1 have known problems with threads,
368 which can cause strange errors in a number of modules (for
369 instance, the 'test_signal' test script will hang forever.)
370 Turning off threads (with --with-threads=no) or upgrading to
371 BSDI 4.1 solves this problem.
373 DEC Unix: Run configure with --with-dec-threads, or with
374 --with-threads=no if no threads are desired (threads are on by
375 default). When using GCC, it is possible to get an internal
376 compiler error if optimization is used. This was reported for
377 GCC 2.7.2.3 on selectmodule.c. Manually compile the affected
378 file without optimization to solve the problem.
380 DEC Ultrix: compile with GCC to avoid bugs in the native compiler,
381 and pass SHELL=/bin/sh5 to Make when installing.
383 AIX: A complete overhaul of the shared library support is now in
384 place. See Misc/AIX-NOTES for some notes on how it's done.
385 (The optimizer bug reported at this place in previous releases
386 has been worked around by a minimal code change.) If you get
387 errors about pthread_* functions, during compile or during
388 testing, try setting CC to a thread-safe (reentrant) compiler,
389 like "cc_r". For full C++ module support, set CC="xlC_r" (or
390 CC="xlC" without thread support).
392 AIX 5.3: To build a 64-bit version with IBM's compiler, I used the
395 export PATH=/usr/bin:/usr/vacpp/bin
396 ./configure --with-gcc="xlc_r -q64" --with-cxx="xlC_r -q64" \
397 --disable-ipv6 AR="ar -X64"
400 HP-UX: When using threading, you may have to add -D_REENTRANT to the
401 OPT variable in the top-level Makefile; reported by Pat Knight,
402 this seems to make a difference (at least for HP-UX 10.20)
403 even though pyconfig.h defines it. This seems unnecessary when
404 using HP/UX 11 and later - threading seems to work "out of the
407 HP-UX ia64: When building on the ia64 (Itanium) platform using HP's
408 compiler, some experience has shown that the compiler's
409 optimiser produces a completely broken version of python
410 (see http://www.python.org/sf/814976). To work around this,
411 edit the Makefile and remove -O from the OPT line.
413 To build a 64-bit executable on an Itanium 2 system using HP's
414 compiler, use these environment variables:
419 LDFLAGS="+DD64 -lxnet"
421 and call configure as:
423 ./configure --without-gcc
425 then *unset* the environment variables again before running
426 make. (At least one of these flags causes the build to fail
427 if it remains set.) You still have to edit the Makefile and
428 remove -O from the OPT line.
430 HP PA-RISC 2.0: A recent bug report (http://www.python.org/sf/546117)
431 suggests that the C compiler in this 64-bit system has bugs
432 in the optimizer that break Python. Compiling without
433 optimization solves the problems.
435 SCO: The following apply to SCO 3 only; Python builds out of the box
436 on SCO 5 (or so we've heard).
438 1) Everything works much better if you add -U__STDC__ to the
439 defs. This is because all the SCO header files are broken.
440 Anything that isn't mentioned in the C standard is
441 conditionally excluded when __STDC__ is defined.
443 2) Due to the U.S. export restrictions, SCO broke the crypt
444 stuff out into a separate library, libcrypt_i.a so the LIBS
447 LIBS=' -lsocket -lcrypt_i'
449 UnixWare: There are known bugs in the math library of the system, as well as
450 problems in the handling of threads (calling fork in one
451 thread may interrupt system calls in others). Therefore, test_math and
452 tests involving threads will fail until those problems are fixed.
454 QNX: Chris Herborth (chrish@qnx.com) writes:
455 configure works best if you use GNU bash; a port is available on
456 ftp.qnx.com in /usr/free. I used the following process to build,
457 test and install Python 1.5.x under QNX:
459 1) CONFIG_SHELL=/usr/local/bin/bash CC=cc RANLIB=: \
460 ./configure --verbose --without-gcc --with-libm=""
462 2) edit Modules/Setup to activate everything that makes sense for
463 your system... tested here at QNX with the following modules:
465 array, audioop, binascii, cPickle, cStringIO, cmath,
466 crypt, curses, errno, fcntl, gdbm, grp, imageop,
467 _locale, math, md5, new, operator, parser, pcre,
468 posix, pwd, readline, regex, reop, rgbimg, rotor,
469 select, signal, socket, soundex, strop, struct,
470 syslog, termios, time, timing, zlib, audioop, imageop, rgbimg
472 3) make SHELL=/usr/local/bin/bash
474 or, if you feel the need for speed:
476 make SHELL=/usr/local/bin/bash OPT="-5 -Oil+nrt"
478 4) make SHELL=/usr/local/bin/bash test
480 Using GNU readline 2.2 seems to behave strangely, but I
481 think that's a problem with my readline 2.2 port. :-\
483 5) make SHELL=/usr/local/bin/bash install
485 If you get SIGSEGVs while running Python (I haven't yet, but
486 I've only run small programs and the test cases), you're
487 probably running out of stack; the default 32k could be a
488 little tight. To increase the stack size, edit the Makefile
489 to read: LDFLAGS = -N 48k
491 BeOS: See Misc/BeOS-NOTES for notes about compiling/installing
492 Python on BeOS R3 or later. Note that only the PowerPC
493 platform is supported for R3; both PowerPC and x86 are
496 Cray T3E: Mark Hadfield (m.hadfield@niwa.co.nz) writes:
497 Python can be built satisfactorily on a Cray T3E but based on
498 my experience with the NIWA T3E (2002-05-22, version 2.2.1)
499 there are a few bugs and gotchas. For more information see a
500 thread on comp.lang.python in May 2002 entitled "Building
503 1) Use Cray's cc and not gcc. The latter was reported not to
504 work by Konrad Hinsen. It may work now, but it may not.
506 2) To set sys.platform to something sensible, pass the
507 following environment variable to the configure script:
511 2) Run configure with option "--enable-unicode=ucs4".
513 3) The Cray T3E does not support dynamic linking, so extension
514 modules have to be built by adding (or uncommenting) lines
515 in Modules/Setup. The minimum set of modules is
517 posix, new, _sre, unicodedata
519 On NIWA's vanilla T3E system the following have also been
520 included successfully:
522 _codecs, _locale, _socket, _symtable, _testcapi, _weakref
523 array, binascii, cmath, cPickle, crypt, cStringIO, dbm
524 errno, fcntl, grp, math, md5, operator, parser, pcre, pwd
525 regex, rotor, select, struct, strop, syslog, termios
526 time, timing, xreadlines
528 4) Once the python executable and library have been built, make
529 will execute setup.py, which will attempt to build remaining
530 extensions and link them dynamically. Each of these attempts
531 will fail but should not halt the make process. This is
534 5) Running "make test" uses a lot of resources and causes
535 problems on our system. You might want to try running tests
536 singly or in small groups.
538 SGI: SGI's standard "make" utility (/bin/make or /usr/bin/make)
539 does not check whether a command actually changed the file it
540 is supposed to build. This means that whenever you say "make"
541 it will redo the link step. The remedy is to use SGI's much
542 smarter "smake" utility (/usr/sbin/smake), or GNU make. If
543 you set the first line of the Makefile to #!/usr/sbin/smake
544 smake will be invoked by make (likewise for GNU make).
546 WARNING: There are bugs in the optimizer of some versions of
547 SGI's compilers that can cause bus errors or other strange
548 behavior, especially on numerical operations. To avoid this,
549 try building with "make OPT=".
551 OS/2: If you are running Warp3 or Warp4 and have IBM's VisualAge C/C++
552 compiler installed, just change into the pc\os2vacpp directory
553 and type NMAKE. Threading and sockets are supported by default
554 in the resulting binaries of PYTHON15.DLL and PYTHON.EXE.
556 Monterey (64-bit AIX): The current Monterey C compiler (Visual Age)
557 uses the OBJECT_MODE={32|64} environment variable to set the
558 compilation mode to either 32-bit or 64-bit (32-bit mode is
559 the default). Presumably you want 64-bit compilation mode for
560 this 64-bit OS. As a result you must first set OBJECT_MODE=64
561 in your environment before configuring (./configure) or
562 building (make) Python on Monterey.
564 Reliant UNIX: The thread support does not compile on Reliant UNIX, and
565 there is a (minor) problem in the configure script for that
566 platform as well. This should be resolved in time for a
569 MacOSX: The tests will crash on both 10.1 and 10.2 with SEGV in
570 test_re and test_sre due to the small default stack size. If
571 you set the stack size to 2048 before doing a "make test" the
572 failure can be avoided. If you're using the tcsh (the default
573 on OSX), or csh shells use "limit stacksize 2048" and for the
574 bash shell, use "ulimit -s 2048".
576 On naked Darwin you may want to add the configure option
577 "--disable-toolbox-glue" to disable the glue code for the Carbon
578 interface modules. The modules themselves are currently only built
579 if you add the --enable-framework option, see below.
581 On a clean OSX /usr/local does not exist. Do a
582 "sudo mkdir -m 775 /usr/local"
583 before you do a make install. It is probably not a good idea to
584 do "sudo make install" which installs everything as superuser,
585 as this may later cause problems when installing distutils-based
588 Some people have reported problems building Python after using "fink"
589 to install additional unix software. Disabling fink (remove all
590 references to /sw from your .profile or .login) should solve this.
592 You may want to try the configure option "--enable-framework"
593 which installs Python as a framework. The location can be set
594 as argument to the --enable-framework option (default
595 /Library/Frameworks). A framework install is probably needed if you
596 want to use any Aqua-based GUI toolkit (whether Tkinter, wxPython,
597 Carbon, Cocoa or anything else).
599 You may also want to try the configure option "--enable-universalsdk"
600 which builds Python as a universal binary with support for the
601 i386 and PPC architetures. This requires Xcode 2.1 or later to build.
603 See Mac/OSX/README for more information on framework and
606 Cygwin: With recent (relative to the time of writing, 2001-12-19)
607 Cygwin installations, there are problems with the interaction
608 of dynamic linking and fork(). This manifests itself in build
609 failures during the execution of setup.py.
611 There are two workarounds that both enable Python (albeit
612 without threading support) to build and pass all tests on
613 NT/2000 (and most likely XP as well, though reports of testing
614 on XP would be appreciated).
618 (a) the band-aid fix is to link the _socket module statically
619 rather than dynamically (which is the default).
621 To do this, run "./configure --with-threads=no" including any
622 other options you need (--prefix, etc.). Then in Modules/Setup
626 #_socket socketmodule.c \
627 # -DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \
628 # -L$(SSL)/lib -lssl -lcrypto
630 and remove "local/" from the SSL variable. Finally, just run
633 (b) The "proper" fix is to rebase the Cygwin DLLs to prevent
634 base address conflicts. Details on how to do this can be
635 found in the following mail:
637 http://sources.redhat.com/ml/cygwin/2001-12/msg00894.html
639 It is hoped that a version of this solution will be
640 incorporated into the Cygwin distribution fairly soon.
642 Two additional problems:
644 (1) Threading support should still be disabled due to a known
645 bug in Cygwin pthreads that causes test_threadedtempfile to
648 (2) The _curses module does not build. This is a known
649 Cygwin ncurses problem that should be resolved the next time
650 that this package is released.
652 On older versions of Cygwin, test_poll may hang and test_strftime
655 The situation on 9X/Me is not accurately known at present.
656 Some time ago, there were reports that the following
657 regression tests failed:
663 Due to the test_select hang on 9X/Me, one should run the
664 regression test using the following:
666 make TESTOPTS='-l -x test_select' test
668 News regarding these platforms with more recent Cygwin
669 versions would be appreciated!
671 AtheOS: From Octavian Cerna <tavy at ylabs.com>:
675 Make sure you have shared versions of the libraries you
676 want to use with Python. You will have to compile them
677 yourself, or download precompiled packages.
679 Recommended libraries:
687 $ ./configure --prefix=/usr/python
690 Python is always built as a shared library, otherwise
691 dynamic loading would not work.
700 # pkgmanager -a /usr/python
705 - large file support: due to a stdio bug in glibc/libio,
706 access to large files may not work correctly. fseeko()
707 tries to seek to a negative offset. ftello() returns a
708 negative offset, it looks like a 32->64bit
709 sign-extension issue. The lowlevel functions (open,
711 - sockets: AF_UNIX is defined in the C library and in
712 Python, but not implemented in the system.
713 - select: poll is available in the C library, but does not
714 work (It does not return POLLNVAL for bad fds and
716 - posix: statvfs and fstatvfs always return ENOSYS.
718 - mmap: not yet implemented in AtheOS
719 - nis: broken (on an unconfigured system
720 yp_get_default_domain() returns junk instead of
722 - dl: dynamic loading doesn't work via dlopen()
723 - resource: getrimit and setrlimit are not yet
726 - if you are getting segmentation faults, you probably are
727 low on memory. AtheOS doesn't handle very well an
728 out-of-memory condition and simply SEGVs the process.
738 Configuring the bsddb and dbm modules
739 -------------------------------------
741 Beginning with Python version 2.3, the PyBsddb package
742 <http://pybsddb.sf.net/> was adopted into Python as the bsddb package,
743 exposing a set of package-level functions which provide
744 backwards-compatible behavior. Only versions 3.3 through 4.4 of
745 Sleepycat's libraries provide the necessary API, so older versions
746 aren't supported through this interface. The old bsddb module has
747 been retained as bsddb185, though it is not built by default. Users
748 wishing to use it will have to tweak Modules/Setup to build it. The
749 dbm module will still be built against the Sleepycat libraries if
750 other preferred alternatives (ndbm, gdbm) are not found.
752 Building the sqlite3 module
753 ---------------------------
755 To build the sqlite3 module, you'll need the sqlite3 or libsqlite3
756 packages installed, including the header files. Many modern operating
757 systems distribute the headers in a separate package to the library -
758 often it will be the same name as the main package, but with a -dev or
761 The version of pysqlite2 that's including in Python needs sqlite3 3.0.8
762 or later. setup.py attempts to check that it can find a correct version.
767 As of Python 2.0, threads are enabled by default. If you wish to
768 compile without threads, or if your thread support is broken, pass the
769 --with-threads=no switch to configure. Unfortunately, on some
770 platforms, additional compiler and/or linker options are required for
771 threads to work properly. Below is a table of those options,
772 collected by Bill Janssen. We would love to automate this process
773 more, but the information below is not enough to write a patch for the
774 configure.in file, so manual intervention is required. If you patch
775 the configure.in file and are confident that the patch works, please
776 send in the patch. (Don't bother patching the configure script itself
777 -- it is regenerated each time the configure.in file changes.)
779 Compiler switches for threads
780 .............................
782 The definition of _REENTRANT should be configured automatically, if
783 that does not work on your system, or if _REENTRANT is defined
784 incorrectly, please report that as a bug.
786 OS/Compiler/threads Switches for use with threads
787 (POSIX is draft 10, DCE is draft 4) compile & link
789 SunOS 5.{1-5}/{gcc,SunPro cc}/solaris -mt
790 SunOS 5.5/{gcc,SunPro cc}/POSIX (nothing)
791 DEC OSF/1 3.x/cc/DCE -threads
792 (butenhof@zko.dec.com)
793 Digital UNIX 4.x/cc/DCE -threads
794 (butenhof@zko.dec.com)
795 Digital UNIX 4.x/cc/POSIX -pthread
796 (butenhof@zko.dec.com)
797 AIX 4.1.4/cc_r/d7 (nothing)
799 AIX 4.1.4/cc_r4/DCE (nothing)
801 IRIX 6.2/cc/POSIX (nothing)
805 Linker (ld) libraries and flags for threads
806 ...........................................
808 OS/threads Libraries/switches for use with threads
810 SunOS 5.{1-5}/solaris -lthread
811 SunOS 5.5/POSIX -lpthread
812 DEC OSF/1 3.x/DCE -lpthreads -lmach -lc_r -lc
813 (butenhof@zko.dec.com)
814 Digital UNIX 4.x/DCE -lpthreads -lpthread -lmach -lexc -lc
815 (butenhof@zko.dec.com)
816 Digital UNIX 4.x/POSIX -lpthread -lmach -lexc -lc
817 (butenhof@zko.dec.com)
818 AIX 4.1.4/{draft7,DCE} (nothing)
820 IRIX 6.2/POSIX -lpthread
821 (jph@emilia.engr.sgi.com)
824 Building a shared libpython
825 ---------------------------
827 Starting with Python 2.3, the majority of the interpreter can be built
828 into a shared library, which can then be used by the interpreter
829 executable, and by applications embedding Python. To enable this feature,
830 configure with --enable-shared.
832 If you enable this feature, the same object files will be used to create
833 a static library. In particular, the static library will contain object
834 files using position-independent code (PIC) on platforms where PIC flags
835 are needed for the shared library.
838 Configuring additional built-in modules
839 ---------------------------------------
841 Starting with Python 2.1, the setup.py script at the top of the source
842 distribution attempts to detect which modules can be built and
843 automatically compiles them. Autodetection doesn't always work, so
844 you can still customize the configuration by editing the Modules/Setup
845 file; but this should be considered a last resort. The rest of this
846 section only applies if you decide to edit the Modules/Setup file.
847 You also need this to enable static linking of certain modules (which
848 is needed to enable profiling on some systems).
850 This file is initially copied from Setup.dist by the configure script;
851 if it does not exist yet, create it by copying Modules/Setup.dist
852 yourself (configure will never overwrite it). Never edit Setup.dist
853 -- always edit Setup or Setup.local (see below). Read the comments in
854 the file for information on what kind of edits are allowed. When you
855 have edited Setup in the Modules directory, the interpreter will
856 automatically be rebuilt the next time you run make (in the toplevel
859 Many useful modules can be built on any Unix system, but some optional
860 modules can't be reliably autodetected. Often the quickest way to
861 determine whether a particular module works or not is to see if it
862 will build: enable it in Setup, then if you get compilation or link
863 errors, disable it -- you're either missing support or need to adjust
864 the compilation and linking parameters for that module.
866 On SGI IRIX, there are modules that interface to many SGI specific
867 system libraries, e.g. the GL library and the audio hardware. These
868 modules will not be built by the setup.py script.
870 In addition to the file Setup, you can also edit the file Setup.local.
871 (the makesetup script processes both). You may find it more
872 convenient to edit Setup.local and leave Setup alone. Then, when
873 installing a new Python version, you can copy your old Setup.local
877 Setting the optimization/debugging options
878 ------------------------------------------
880 If you want or need to change the optimization/debugging options for
881 the C compiler, assign to the OPT variable on the toplevel make
882 command; e.g. "make OPT=-g" will build a debugging version of Python
883 on most platforms. The default is OPT=-O; a value for OPT in the
884 environment when the configure script is run overrides this default
885 (likewise for CC; and the initial value for LIBS is used as the base
886 set of libraries to link with).
888 When compiling with GCC, the default value of OPT will also include
889 the -Wall and -Wstrict-prototypes options.
891 Additional debugging code to help debug memory management problems can
892 be enabled by using the --with-pydebug option to the configure script.
894 For flags that change binary compatibility, use the EXTRA_CFLAGS
901 If you want C profiling turned on, the easiest way is to run configure
902 with the CC environment variable to the necessary compiler
903 invocation. For example, on Linux, this works for profiling using
906 CC="gcc -pg" ./configure
908 Note that on Linux, gprof apparently does not work for shared
909 libraries. The Makefile/Setup mechanism can be used to compile and
910 link most extension modules statically.
916 To test the interpreter, type "make test" in the top-level directory.
917 This runs the test set twice (once with no compiled files, once with
918 the compiled files left by the previous test run). The test set
919 produces some output. You can generally ignore the messages about
920 skipped tests due to optional features which can't be imported.
921 If a message is printed about a failed test or a traceback or core
922 dump is produced, something is wrong. On some Linux systems (those
923 that are not yet using glibc 6), test_strftime fails due to a
924 non-standard implementation of strftime() in the C library. Please
925 ignore this, or upgrade to glibc version 6.
927 IMPORTANT: If the tests fail and you decide to mail a bug report,
928 *don't* include the output of "make test". It is useless. Run the
929 failing test manually, as follows:
931 ./python ./Lib/test/test_whatever.py
933 (substituting the top of the source tree for '.' if you built in a
934 different directory). This runs the test in verbose mode.
940 To install the Python binary, library modules, shared library modules
941 (see below), include files, configuration files, and the manual page,
946 This will install all platform-independent files in subdirectories of
947 the directory given with the --prefix option to configure or to the
948 `prefix' Make variable (default /usr/local). All binary and other
949 platform-specific files will be installed in subdirectories if the
950 directory given by --exec-prefix or the `exec_prefix' Make variable
951 (defaults to the --prefix directory) is given.
953 If DESTDIR is set, it will be taken as the root directory of the
954 installation, and files will be installed into $(DESTDIR)$(prefix),
955 $(DESTDIR)$(exec_prefix), etc.
957 All subdirectories created will have Python's version number in their
958 name, e.g. the library modules are installed in
959 "/usr/local/lib/python<version>/" by default, where <version> is the
960 <major>.<minor> release number (e.g. "2.1"). The Python binary is
961 installed as "python<version>" and a hard link named "python" is
962 created. The only file not installed with a version number in its
963 name is the manual page, installed as "/usr/local/man/man1/python.1"
966 If you have a previous installation of Python that you don't
967 want to replace yet, use
971 This installs the same set of files as "make install" except it
972 doesn't create the hard link to "python<version>" named "python" and
973 it doesn't install the manual page at all.
975 The only thing you may have to install manually is the Python mode for
976 Emacs found in Misc/python-mode.el. (But then again, more recent
977 versions of Emacs may already have it.) Follow the instructions that
978 came with Emacs for installation of site-specific files.
980 On Mac OS X, if you have configured Python with --enable-framework, you
981 should use "make frameworkinstall" to do the installation. Note that this
982 installs the Python executable in a place that is not normally on your
983 PATH, you may want to set up a symlink in /usr/local/bin.
986 Configuration options and variables
987 -----------------------------------
989 Some special cases are handled by passing options to the configure
992 WARNING: if you rerun the configure script with different options, you
993 must run "make clean" before rebuilding. Exceptions to this rule:
994 after changing --prefix or --exec-prefix, all you need to do is remove
997 --with(out)-gcc: The configure script uses gcc (the GNU C compiler) if
998 it finds it. If you don't want this, or if this compiler is
999 installed but broken on your platform, pass the option
1000 --without-gcc. You can also pass "CC=cc" (or whatever the
1001 name of the proper C compiler is) in the environment, but the
1002 advantage of using --without-gcc is that this option is
1003 remembered by the config.status script for its --recheck
1006 --prefix, --exec-prefix: If you want to install the binaries and the
1007 Python library somewhere else than in /usr/local/{bin,lib},
1008 you can pass the option --prefix=DIRECTORY; the interpreter
1009 binary will be installed as DIRECTORY/bin/python and the
1010 library files as DIRECTORY/lib/python/*. If you pass
1011 --exec-prefix=DIRECTORY (as well) this overrides the
1012 installation prefix for architecture-dependent files (like the
1013 interpreter binary). Note that --prefix=DIRECTORY also
1014 affects the default module search path (sys.path), when
1015 Modules/config.c is compiled. Passing make the option
1016 prefix=DIRECTORY (and/or exec_prefix=DIRECTORY) overrides the
1017 prefix set at configuration time; this may be more convenient
1018 than re-running the configure script if you change your mind
1019 about the install prefix.
1021 --with-readline: This option is no longer supported. GNU
1022 readline is automatically enabled by setup.py when present.
1024 --with-threads: On most Unix systems, you can now use multiple
1025 threads, and support for this is enabled by default. To
1026 disable this, pass --with-threads=no. If the library required
1027 for threads lives in a peculiar place, you can use
1028 --with-thread=DIRECTORY. IMPORTANT: run "make clean" after
1029 changing (either enabling or disabling) this option, or you
1030 will get link errors! Note: for DEC Unix use
1031 --with-dec-threads instead.
1033 --with-sgi-dl: On SGI IRIX 4, dynamic loading of extension modules is
1034 supported by the "dl" library by Jack Jansen, which is
1035 ftp'able from ftp://ftp.cwi.nl/pub/dynload/dl-1.6.tar.Z.
1036 This is enabled (after you've ftp'ed and compiled the dl
1037 library) by passing --with-sgi-dl=DIRECTORY where DIRECTORY
1038 is the absolute pathname of the dl library. (Don't bother on
1039 IRIX 5, it already has dynamic linking using SunOS style
1040 shared libraries.) THIS OPTION IS UNSUPPORTED.
1042 --with-dl-dld: Dynamic loading of modules is rumored to be supported
1043 on some other systems: VAX (Ultrix), Sun3 (SunOS 3.4), Sequent
1044 Symmetry (Dynix), and Atari ST. This is done using a
1045 combination of the GNU dynamic loading package
1046 (ftp://ftp.cwi.nl/pub/dynload/dl-dld-1.1.tar.Z) and an
1047 emulation of the SGI dl library mentioned above (the emulation
1049 ftp://ftp.cwi.nl/pub/dynload/dld-3.2.3.tar.Z). To
1050 enable this, ftp and compile both libraries, then call
1051 configure, passing it the option
1052 --with-dl-dld=DL_DIRECTORY,DLD_DIRECTORY where DL_DIRECTORY is
1053 the absolute pathname of the dl emulation library and
1054 DLD_DIRECTORY is the absolute pathname of the GNU dld library.
1055 (Don't bother on SunOS 4 or 5, they already have dynamic
1056 linking using shared libraries.) THIS OPTION IS UNSUPPORTED.
1058 --with-libm, --with-libc: It is possible to specify alternative
1059 versions for the Math library (default -lm) and the C library
1060 (default the empty string) using the options
1061 --with-libm=STRING and --with-libc=STRING, respectively. For
1062 example, if your system requires that you pass -lc_s to the C
1063 compiler to use the shared C library, you can pass
1064 --with-libc=-lc_s. These libraries are passed after all other
1065 libraries, the C library last.
1067 --with-libs='libs': Add 'libs' to the LIBS that the python interpreter
1070 --with-cxx-main=<compiler>: If you plan to use C++ extension modules,
1071 then -- on some platforms -- you need to compile python's main()
1072 function with the C++ compiler. With this option, make will use
1073 <compiler> to compile main() *and* to link the python executable.
1074 It is likely that the resulting executable depends on the C++
1075 runtime library of <compiler>. (The default is --without-cxx-main.)
1077 There are platforms that do not require you to build Python
1078 with a C++ compiler in order to use C++ extension modules.
1079 E.g., x86 Linux with ELF shared binaries and GCC 3.x, 4.x is such
1080 a platform. We recommend that you configure Python
1081 --without-cxx-main on those platforms because a mismatch
1082 between the C++ compiler version used to build Python and to
1083 build a C++ extension module is likely to cause a crash at
1086 The Python installation also stores the variable CXX that
1087 determines, e.g., the C++ compiler distutils calls by default
1088 to build C++ extensions. If you set CXX on the configure command
1089 line to any string of non-zero length, then configure won't
1090 change CXX. If you do not preset CXX but pass
1091 --with-cxx-main=<compiler>, then configure sets CXX=<compiler>.
1092 In all other cases, configure looks for a C++ compiler by
1093 some common names (c++, g++, gcc, CC, cxx, cc++, cl) and sets
1094 CXX to the first compiler it finds. If it does not find any
1095 C++ compiler, then it sets CXX="".
1097 Similarly, if you want to change the command used to link the
1098 python executable, then set LINKCC on the configure command line.
1101 --with-pydebug: Enable additional debugging code to help track down
1102 memory management problems. This allows printing a list of all
1103 live objects when the interpreter terminates.
1105 --with(out)-universal-newlines: enable reading of text files with
1106 foreign newline convention (default: enabled). In other words,
1107 any of \r, \n or \r\n is acceptable as end-of-line character.
1108 If enabled import and execfile will automatically accept any newline
1109 in files. Python code can open a file with open(file, 'U') to
1110 read it in universal newline mode. THIS OPTION IS UNSUPPORTED.
1112 --with-tsc: Profile using the Pentium timestamping counter (TSC).
1114 --with-system-ffi: Build the _ctypes extension module using an ffi
1115 library installed on the system.
1118 Building for multiple architectures (using the VPATH feature)
1119 -------------------------------------------------------------
1121 If your file system is shared between multiple architectures, it
1122 usually is not necessary to make copies of the sources for each
1123 architecture you want to support. If the make program supports the
1124 VPATH feature, you can create an empty build directory for each
1125 architecture, and in each directory run the configure script (on the
1126 appropriate machine with the appropriate options). This creates the
1127 necessary subdirectories and the Makefiles therein. The Makefiles
1128 contain a line VPATH=... which points to a directory containing the
1129 actual sources. (On SGI systems, use "smake -J1" instead of "make" if
1130 you use VPATH -- don't try gnumake.)
1132 For example, the following is all you need to build a minimal Python
1133 in /usr/tmp/python (assuming ~guido/src/python is the toplevel
1134 directory and you want to build in /usr/tmp/python):
1136 $ mkdir /usr/tmp/python
1137 $ cd /usr/tmp/python
1138 $ ~guido/src/python/configure
1144 Note that configure copies the original Setup file to the build
1145 directory if it finds no Setup file there. This means that you can
1146 edit the Setup file for each architecture independently. For this
1147 reason, subsequent changes to the original Setup file are not tracked
1148 automatically, as they might overwrite local changes. To force a copy
1149 of a changed original Setup file, delete the target Setup file. (The
1150 makesetup script supports multiple input files, so if you want to be
1151 fancy you can change the rules to create an empty Setup.local if it
1152 doesn't exist and run it with arguments $(srcdir)/Setup Setup.local;
1153 however this assumes that you only need to add modules.)
1156 Building on non-UNIX systems
1157 ----------------------------
1159 For Windows (2000/NT/ME/98/95), assuming you have MS VC++ 7.1, the
1160 project files are in PCbuild, the workspace is pcbuild.dsw. See
1161 PCbuild\readme.txt for detailed instructions.
1163 For other non-Unix Windows compilers, in particular MS VC++ 6.0 and
1164 for OS/2, enter the directory "PC" and read the file "readme.txt".
1166 For the Mac, a separate source distribution will be made available,
1167 for use with the CodeWarrior compiler. If you are interested in Mac
1168 development, join the PythonMac Special Interest Group
1169 (http://www.python.org/sigs/pythonmac-sig/, or send email to
1170 pythonmac-sig-request@python.org).
1172 Of course, there are also binary distributions available for these
1173 platforms -- see http://www.python.org/.
1175 To port Python to a new non-UNIX system, you will have to fake the
1176 effect of running the configure script manually (for Mac and PC, this
1177 has already been done for you). A good start is to copy the file
1178 pyconfig.h.in to pyconfig.h and edit the latter to reflect the actual
1179 configuration of your system. Most symbols must simply be defined as
1180 1 only if the corresponding feature is present and can be left alone
1181 otherwise; however the *_t type symbols must be defined as some
1182 variant of int if they need to be defined at all.
1184 For all platforms, it's important that the build arrange to define the
1185 preprocessor symbol NDEBUG on the compiler command line in a release
1186 build of Python (else assert() calls remain in the code, hurting
1187 release-build performance). The Unix, Windows and Mac builds already
1191 Miscellaneous issues
1192 ====================
1197 There's an excellent Emacs editing mode for Python code; see the file
1198 Misc/python-mode.el. Originally written by the famous Tim Peters, it
1199 is now maintained by the equally famous Barry Warsaw (it's no
1200 coincidence that they now both work on the same team). The latest
1201 version, along with various other contributed Python-related Emacs
1202 goodies, is online at http://www.python.org/emacs/python-mode. And
1203 if you are planning to edit the Python C code, please pick up the
1204 latest version of CC Mode http://www.python.org/emacs/cc-mode; it
1205 contains a "python" style used throughout most of the Python C source
1206 files. (Newer versions of Emacs or XEmacs may already come with the
1207 latest version of python-mode.)
1213 The setup.py script automatically configures this when it detects a
1214 usable Tcl/Tk installation. This requires Tcl/Tk version 8.0 or
1217 For more Tkinter information, see the Tkinter Resource page:
1218 http://www.python.org/topics/tkinter/
1220 There are demos in the Demo/tkinter directory.
1222 Note that there's a Python module called "Tkinter" (capital T) which
1223 lives in Lib/lib-tk/Tkinter.py, and a C module called "_tkinter"
1224 (lower case t and leading underscore) which lives in
1225 Modules/_tkinter.c. Demos and normal Tk applications import only the
1226 Python Tkinter module -- only the latter imports the C _tkinter
1227 module. In order to find the C _tkinter module, it must be compiled
1228 and linked into the Python interpreter -- the setup.py script does
1229 this. In order to find the Python Tkinter module, sys.path must be
1230 set correctly -- normal installation takes care of this.
1233 Distribution structure
1234 ----------------------
1236 Most subdirectories have their own README files. Most files have
1239 BeOS/ Files specific to the BeOS port
1240 Demo/ Demonstration scripts, modules and programs
1241 Doc/ Documentation sources (LaTeX)
1242 Grammar/ Input for the parser generator
1243 Include/ Public header files
1244 LICENSE Licensing information
1245 Lib/ Python library modules
1246 Mac/ Macintosh specific resources
1247 Makefile.pre.in Source from which config.status creates the Makefile.pre
1248 Misc/ Miscellaneous useful files
1249 Modules/ Implementation of most built-in modules
1250 Objects/ Implementation of most built-in object types
1251 PC/ Files specific to PC ports (DOS, Windows, OS/2)
1252 PCbuild/ Build directory for Microsoft Visual C++
1253 Parser/ The parser and tokenizer and their input handling
1254 Python/ The byte-compiler and interpreter
1255 README The file you're reading now
1256 Tools/ Some useful programs written in Python
1257 pyconfig.h.in Source from which pyconfig.h is created (GNU autoheader output)
1258 configure Configuration shell script (GNU autoconf output)
1259 configure.in Configuration specification (input for GNU autoconf)
1260 install-sh Shell script used to install files
1261 setup.py Python script used to build extension modules
1263 The following files will (may) be created in the toplevel directory by
1264 the configuration and build processes:
1266 Makefile Build rules
1267 Makefile.pre Build rules before running Modules/makesetup
1268 buildno Keeps track of the build number
1269 config.cache Cache of configuration variables
1270 pyconfig.h Configuration header
1271 config.log Log from last configure run
1272 config.status Status from last run of the configure script
1273 getbuildinfo.o Object file from Modules/getbuildinfo.c
1274 libpython<version>.a The library archive
1275 python The executable interpreter
1276 tags, TAGS Tags files for vi and Emacs
1283 --Guido van Rossum (home page: http://www.python.org/~guido/)