1 This is Python version 2.6 alpha 0
2 ==================================
4 Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007
5 Python Software Foundation.
8 Copyright (c) 2000 BeOpen.com.
11 Copyright (c) 1995-2001 Corporation for National Research Initiatives.
14 Copyright (c) 1991-1995 Stichting Mathematisch Centrum.
21 See the file "LICENSE" for information on the history of this
22 software, terms & conditions for usage, and a DISCLAIMER OF ALL
25 This Python distribution contains no GNU General Public Licensed
26 (GPLed) code so it may be used in proprietary projects just like prior
27 Python distributions. There are interfaces to some GNU code but these
28 are entirely optional.
30 All trademarks referenced herein are property of their respective
34 What's new in this release?
35 ---------------------------
37 See the file "Misc/NEWS".
40 If you don't read instructions
41 ------------------------------
43 Congratulations on getting this far. :-)
45 To start building right away (on UNIX): type "./configure" in the
46 current directory and when it finishes, type "make". This creates an
47 executable "./python"; to install in /usr/local, first do "su root"
48 and then "make install".
50 The section `Build instructions' below is still recommended reading.
53 What is Python anyway?
54 ----------------------
56 Python is an interpreted, interactive object-oriented programming
57 language suitable (amongst other uses) for distributed application
58 development, scripting, numeric computing and system testing. Python
59 is often compared to Tcl, Perl, Java, JavaScript, Visual Basic or
60 Scheme. To find out more about what Python can do for you, point your
61 browser to http://www.python.org/.
64 How do I learn Python?
65 ----------------------
67 The official tutorial is still a good place to start; see
68 http://docs.python.org/ for online and downloadable versions, as well
69 as a list of other introductions, and reference documentation.
71 There's a quickly growing set of books on Python. See
72 http://wiki.python.org/moin/PythonBooks for a list.
78 All documentation is provided online in a variety of formats. In
79 order of importance for new users: Tutorial, Library Reference,
80 Language Reference, Extending & Embedding, and the Python/C API. The
81 Library Reference is especially of immense value since much of
82 Python's power is described there, including the built-in data types
85 All documentation is also available online at the Python web site
86 (http://docs.python.org/, see below). It is available online for
87 occasional reference, or can be downloaded in many formats for faster
88 access. The documentation is available in HTML, PostScript, PDF, and
89 LaTeX formats; the LaTeX version is primarily for documentation
90 authors, translators, and people with special formatting requirements.
92 Unfortunately, new-style classes (new in Python 2.2) have not yet been
93 integrated into Python's standard documentation. A collection of
94 pointers to what has been written is at:
96 http://www.python.org/doc/newstyle.html
102 New Python releases and related technologies are published at
103 http://www.python.org/. Come visit us!
105 There's also a Python community web site at
106 http://starship.python.net/.
109 Newsgroups and Mailing Lists
110 ----------------------------
112 Read comp.lang.python, a high-volume discussion newsgroup about
113 Python, or comp.lang.python.announce, a low-volume moderated newsgroup
114 for Python-related announcements. These are also accessible as
115 mailing lists: see http://www.python.org/community/lists.html for an
116 overview of these and many other Python-related mailing lists.
118 Archives are accessible via the Google Groups Usenet archive; see
119 http://groups.google.com/. The mailing lists are also archived, see
120 http://www.python.org/community/lists.html for details.
126 To report or search for bugs, please use the Python Bug
127 Tracker at http://sourceforge.net/bugs/?group_id=5470.
130 Patches and contributions
131 -------------------------
133 To submit a patch or other contribution, please use the Python Patch
134 Manager at http://sourceforge.net/patch/?group_id=5470. Guidelines
135 for patch submission may be found at http://www.python.org/patches/.
137 If you have a proposal to change Python, it's best to submit a Python
138 Enhancement Proposal (PEP) first. All current PEPs, as well as
139 guidelines for submitting a new PEP, are listed at
140 http://www.python.org/peps/.
146 For help, if you can't find it in the manuals or on the web site, it's
147 best to post to the comp.lang.python or the Python mailing list (see
148 above). If you specifically don't want to involve the newsgroup or
149 mailing list, send questions to help@python.org (a group of volunteers
150 who answer questions as they can). The newsgroup is the most
151 efficient way to ask public questions.
157 Before you can build Python, you must first configure it.
158 Fortunately, the configuration and build process has been automated
159 for Unix and Linux installations, so all you usually have to do is
160 type a few commands and sit back. There are some platforms where
161 things are not quite as smooth; see the platform specific notes below.
162 If you want to build for multiple platforms sharing the same source
163 tree, see the section on VPATH below.
165 Start by running the script "./configure", which determines your
166 system configuration and creates the Makefile. (It takes a minute or
167 two -- please be patient!) You may want to pass options to the
168 configure script -- see the section below on configuration options and
169 variables. When it's done, you are ready to run make.
171 To build Python, you normally type "make" in the toplevel directory.
172 If you have changed the configuration, the Makefile may have to be
173 rebuilt. In this case you may have to run make again to correctly
174 build your desired target. The interpreter executable is built in the
177 Once you have built a Python interpreter, see the subsections below on
178 testing and installation. If you run into trouble, see the next
181 Previous versions of Python used a manual configuration process that
182 involved editing the file Modules/Setup. While this file still exists
183 and manual configuration is still supported, it is rarely needed any
184 more: almost all modules are automatically built as appropriate under
185 guidance of the setup.py script, which is run by Make after the
186 interpreter has been built.
192 See also the platform specific notes in the next section.
194 If you run into other trouble, see the FAQ
195 (http://www.python.org/doc/faq) for hints on what can go wrong, and
198 If you rerun the configure script with different options, remove all
199 object files by running "make clean" before rebuilding. Believe it or
200 not, "make clean" sometimes helps to clean up other inexplicable
201 problems as well. Try it before sending in a bug report!
203 If the configure script fails or doesn't seem to find things that
204 should be there, inspect the config.log file.
206 If you get a warning for every file about the -Olimit option being no
207 longer supported, you can ignore it. There's no foolproof way to know
208 whether this option is needed; all we can do is test whether it is
209 accepted without error. On some systems, e.g. older SGI compilers, it
210 is essential for performance (specifically when compiling ceval.c,
211 which has more basic blocks than the default limit of 1000). If the
212 warning bothers you, edit the Makefile to remove "-Olimit 1500" from
215 If you get failures in test_long, or sys.maxint gets set to -1, you
216 are probably experiencing compiler bugs, usually related to
217 optimization. This is a common problem with some versions of gcc, and
218 some vendor-supplied compilers, which can sometimes be worked around
219 by turning off optimization. Consider switching to stable versions
220 (gcc 2.95.2, gcc 3.x, or contact your vendor.)
222 From Python 2.0 onward, all Python C code is ANSI C. Compiling using
223 old K&R-C-only compilers is no longer possible. ANSI C compilers are
224 available for all modern systems, either in the form of updated
225 compilers from the vendor, or one of the free compilers (gcc).
227 If "make install" fails mysteriously during the "compiling the library"
228 step, make sure that you don't have any of the PYTHONPATH or PYTHONHOME
229 environment variables set, as they may interfere with the newly built
230 executable which is compiling the library.
235 A number of features are not supported in Python 2.5 anymore. Some
236 support code is still present, but will be removed in Python 2.6.
237 If you still need to use current Python versions on these systems,
238 please send a message to python-dev@python.org indicating that you
239 volunteer to support this system. For a more detailed discussion
240 regarding no-longer-supported and resupporting platforms, as well
241 as a list of platforms that became or will be unsupported, see PEP 11.
243 More specifically, the following systems are not supported any
250 - Irix 4 and --with-sgi-dl
252 - Systems defining __d6_pthread_create (configure.in)
253 - Systems defining PY_PTHREAD_D4, PY_PTHREAD_D6,
254 or PY_PTHREAD_D7 in thread_pthread.h
255 - Systems using --with-dl-dld
256 - Systems using --without-universal-newlines
259 The following systems are still supported in Python 2.5, but
260 support will be dropped in 2.6:
261 - Systems using --with-wctype-functions
264 Warning on install in Windows 98 and Windows Me
265 -----------------------------------------------
267 Following Microsoft's closing of Extended Support for
268 Windows 98/ME (July 11, 2006), Python 2.6 will stop
269 supporting these platforms. Python development and
270 maintainability becomes easier (and more reliable) when
271 platform specific code targeting OSes with few users
272 and no dedicated expert developers is taken out. The
273 vendor also warns that the OS versions listed above
274 "can expose customers to security risks" and recommends
277 Platform specific notes
278 -----------------------
280 (Some of these may no longer apply. If you find you can build Python
281 on these platforms without the special directions mentioned here,
282 submit a documentation bug report to SourceForge (see Bug Reports
283 above) so we can remove them!)
285 Unix platforms: If your vendor still ships (and you still use) Berkeley DB
286 1.85 you will need to edit Modules/Setup to build the bsddb185
287 module and add a line to sitecustomize.py which makes it the
288 default. In Modules/Setup a line like
290 bsddb185 bsddbmodule.c
292 should work. (You may need to add -I, -L or -l flags to direct the
293 compiler and linker to your include files and libraries.)
295 XXX I think this next bit is out of date:
297 64-bit platforms: The modules audioop, imageop and rgbimg don't work.
298 The setup.py script disables them on 64-bit installations.
299 Don't try to enable them in the Modules/Setup file. They
300 contain code that is quite wordsize sensitive. (If you have a
303 Solaris: When using Sun's C compiler with threads, at least on Solaris
304 2.5.1, you need to add the "-mt" compiler option (the simplest
305 way is probably to specify the compiler with this option as
306 the "CC" environment variable when running the configure
309 When using GCC on Solaris, beware of binutils 2.13 or GCC
310 versions built using it. This mistakenly enables the
311 -zcombreloc option which creates broken shared libraries on
312 Solaris. binutils 2.12 works, and the binutils maintainers
313 are aware of the problem. Binutils 2.13.1 only partially
314 fixed things. It appears that 2.13.2 solves the problem
315 completely. This problem is known to occur with Solaris 2.7
316 and 2.8, but may also affect earlier and later versions of the
319 When the dynamic loader complains about errors finding shared
322 ld.so.1: ./python: fatal: libstdc++.so.5: open failed:
323 No such file or directory
325 you need to first make sure that the library is available on
326 your system. Then, you need to instruct the dynamic loader how
327 to find it. You can choose any of the following strategies:
329 1. When compiling Python, set LD_RUN_PATH to the directories
330 containing missing libraries.
331 2. When running Python, set LD_LIBRARY_PATH to these directories.
332 3. Use crle(8) to extend the search path of the loader.
333 4. Modify the installed GCC specs file, adding -R options into the
336 The complex object fails to compile on Solaris 10 with gcc 3.4 (at
337 least up to 3.4.3). To work around it, define Py_HUGE_VAL as
340 make CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()" -I. -I$(srcdir)/Include'
341 ./python setup.py CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()"'
343 Linux: A problem with threads and fork() was tracked down to a bug in
344 the pthreads code in glibc version 2.0.5; glibc version 2.0.7
345 solves the problem. This causes the popen2 test to fail;
346 problem and solution reported by Pablo Bleyer.
348 Red Hat Linux: Red Hat 9 built Python2.2 in UCS-4 mode and hacked
349 Tcl to support it. To compile Python2.3 with Tkinter, you will
350 need to pass --enable-unicode=ucs4 flag to ./configure.
352 There's an executable /usr/bin/python which is Python
353 1.5.2 on most older Red Hat installations; several key Red Hat tools
354 require this version. Python 2.1.x may be installed as
355 /usr/bin/python2. The Makefile installs Python as
356 /usr/local/bin/python, which may or may not take precedence
357 over /usr/bin/python, depending on how you have set up $PATH.
359 FreeBSD 3.x and probably platforms with NCurses that use libmytinfo or
360 similar: When using cursesmodule, the linking is not done in
361 the correct order with the defaults. Remove "-ltermcap" from
362 the readline entry in Setup, and use as curses entry: "curses
363 cursesmodule.c -lmytinfo -lncurses -ltermcap" - "mytinfo" (so
364 called on FreeBSD) should be the name of the auxiliary library
365 required on your platform. Normally, it would be linked
366 automatically, but not necessarily in the correct order.
368 BSDI: BSDI versions before 4.1 have known problems with threads,
369 which can cause strange errors in a number of modules (for
370 instance, the 'test_signal' test script will hang forever.)
371 Turning off threads (with --with-threads=no) or upgrading to
372 BSDI 4.1 solves this problem.
374 DEC Unix: Run configure with --with-dec-threads, or with
375 --with-threads=no if no threads are desired (threads are on by
376 default). When using GCC, it is possible to get an internal
377 compiler error if optimization is used. This was reported for
378 GCC 2.7.2.3 on selectmodule.c. Manually compile the affected
379 file without optimization to solve the problem.
381 DEC Ultrix: compile with GCC to avoid bugs in the native compiler,
382 and pass SHELL=/bin/sh5 to Make when installing.
384 AIX: A complete overhaul of the shared library support is now in
385 place. See Misc/AIX-NOTES for some notes on how it's done.
386 (The optimizer bug reported at this place in previous releases
387 has been worked around by a minimal code change.) If you get
388 errors about pthread_* functions, during compile or during
389 testing, try setting CC to a thread-safe (reentrant) compiler,
390 like "cc_r". For full C++ module support, set CC="xlC_r" (or
391 CC="xlC" without thread support).
393 AIX 5.3: To build a 64-bit version with IBM's compiler, I used the
396 export PATH=/usr/bin:/usr/vacpp/bin
397 ./configure --with-gcc="xlc_r -q64" --with-cxx="xlC_r -q64" \
398 --disable-ipv6 AR="ar -X64"
401 HP-UX: When using threading, you may have to add -D_REENTRANT to the
402 OPT variable in the top-level Makefile; reported by Pat Knight,
403 this seems to make a difference (at least for HP-UX 10.20)
404 even though pyconfig.h defines it. This seems unnecessary when
405 using HP/UX 11 and later - threading seems to work "out of the
408 HP-UX ia64: When building on the ia64 (Itanium) platform using HP's
409 compiler, some experience has shown that the compiler's
410 optimiser produces a completely broken version of python
411 (see http://www.python.org/sf/814976). To work around this,
412 edit the Makefile and remove -O from the OPT line.
414 To build a 64-bit executable on an Itanium 2 system using HP's
415 compiler, use these environment variables:
420 LDFLAGS="+DD64 -lxnet"
422 and call configure as:
424 ./configure --without-gcc
426 then *unset* the environment variables again before running
427 make. (At least one of these flags causes the build to fail
428 if it remains set.) You still have to edit the Makefile and
429 remove -O from the OPT line.
431 HP PA-RISC 2.0: A recent bug report (http://www.python.org/sf/546117)
432 suggests that the C compiler in this 64-bit system has bugs
433 in the optimizer that break Python. Compiling without
434 optimization solves the problems.
436 SCO: The following apply to SCO 3 only; Python builds out of the box
437 on SCO 5 (or so we've heard).
439 1) Everything works much better if you add -U__STDC__ to the
440 defs. This is because all the SCO header files are broken.
441 Anything that isn't mentioned in the C standard is
442 conditionally excluded when __STDC__ is defined.
444 2) Due to the U.S. export restrictions, SCO broke the crypt
445 stuff out into a separate library, libcrypt_i.a so the LIBS
448 LIBS=' -lsocket -lcrypt_i'
450 UnixWare: There are known bugs in the math library of the system, as well as
451 problems in the handling of threads (calling fork in one
452 thread may interrupt system calls in others). Therefore, test_math and
453 tests involving threads will fail until those problems are fixed.
455 QNX: Chris Herborth (chrish@qnx.com) writes:
456 configure works best if you use GNU bash; a port is available on
457 ftp.qnx.com in /usr/free. I used the following process to build,
458 test and install Python 1.5.x under QNX:
460 1) CONFIG_SHELL=/usr/local/bin/bash CC=cc RANLIB=: \
461 ./configure --verbose --without-gcc --with-libm=""
463 2) edit Modules/Setup to activate everything that makes sense for
464 your system... tested here at QNX with the following modules:
466 array, audioop, binascii, cPickle, cStringIO, cmath,
467 crypt, curses, errno, fcntl, gdbm, grp, imageop,
468 _locale, math, md5, new, operator, parser, pcre,
469 posix, pwd, readline, regex, reop, rgbimg, rotor,
470 select, signal, socket, soundex, strop, struct,
471 syslog, termios, time, timing, zlib, audioop, imageop, rgbimg
473 3) make SHELL=/usr/local/bin/bash
475 or, if you feel the need for speed:
477 make SHELL=/usr/local/bin/bash OPT="-5 -Oil+nrt"
479 4) make SHELL=/usr/local/bin/bash test
481 Using GNU readline 2.2 seems to behave strangely, but I
482 think that's a problem with my readline 2.2 port. :-\
484 5) make SHELL=/usr/local/bin/bash install
486 If you get SIGSEGVs while running Python (I haven't yet, but
487 I've only run small programs and the test cases), you're
488 probably running out of stack; the default 32k could be a
489 little tight. To increase the stack size, edit the Makefile
490 to read: LDFLAGS = -N 48k
492 BeOS: See Misc/BeOS-NOTES for notes about compiling/installing
493 Python on BeOS R3 or later. Note that only the PowerPC
494 platform is supported for R3; both PowerPC and x86 are
497 Cray T3E: Mark Hadfield (m.hadfield@niwa.co.nz) writes:
498 Python can be built satisfactorily on a Cray T3E but based on
499 my experience with the NIWA T3E (2002-05-22, version 2.2.1)
500 there are a few bugs and gotchas. For more information see a
501 thread on comp.lang.python in May 2002 entitled "Building
504 1) Use Cray's cc and not gcc. The latter was reported not to
505 work by Konrad Hinsen. It may work now, but it may not.
507 2) To set sys.platform to something sensible, pass the
508 following environment variable to the configure script:
512 2) Run configure with option "--enable-unicode=ucs4".
514 3) The Cray T3E does not support dynamic linking, so extension
515 modules have to be built by adding (or uncommenting) lines
516 in Modules/Setup. The minimum set of modules is
518 posix, new, _sre, unicodedata
520 On NIWA's vanilla T3E system the following have also been
521 included successfully:
523 _codecs, _locale, _socket, _symtable, _testcapi, _weakref
524 array, binascii, cmath, cPickle, crypt, cStringIO, dbm
525 errno, fcntl, grp, math, md5, operator, parser, pcre, pwd
526 regex, rotor, select, struct, strop, syslog, termios
527 time, timing, xreadlines
529 4) Once the python executable and library have been built, make
530 will execute setup.py, which will attempt to build remaining
531 extensions and link them dynamically. Each of these attempts
532 will fail but should not halt the make process. This is
535 5) Running "make test" uses a lot of resources and causes
536 problems on our system. You might want to try running tests
537 singly or in small groups.
539 SGI: SGI's standard "make" utility (/bin/make or /usr/bin/make)
540 does not check whether a command actually changed the file it
541 is supposed to build. This means that whenever you say "make"
542 it will redo the link step. The remedy is to use SGI's much
543 smarter "smake" utility (/usr/sbin/smake), or GNU make. If
544 you set the first line of the Makefile to #!/usr/sbin/smake
545 smake will be invoked by make (likewise for GNU make).
547 WARNING: There are bugs in the optimizer of some versions of
548 SGI's compilers that can cause bus errors or other strange
549 behavior, especially on numerical operations. To avoid this,
550 try building with "make OPT=".
552 OS/2: If you are running Warp3 or Warp4 and have IBM's VisualAge C/C++
553 compiler installed, just change into the pc\os2vacpp directory
554 and type NMAKE. Threading and sockets are supported by default
555 in the resulting binaries of PYTHON15.DLL and PYTHON.EXE.
557 Monterey (64-bit AIX): The current Monterey C compiler (Visual Age)
558 uses the OBJECT_MODE={32|64} environment variable to set the
559 compilation mode to either 32-bit or 64-bit (32-bit mode is
560 the default). Presumably you want 64-bit compilation mode for
561 this 64-bit OS. As a result you must first set OBJECT_MODE=64
562 in your environment before configuring (./configure) or
563 building (make) Python on Monterey.
565 Reliant UNIX: The thread support does not compile on Reliant UNIX, and
566 there is a (minor) problem in the configure script for that
567 platform as well. This should be resolved in time for a
570 MacOSX: The tests will crash on both 10.1 and 10.2 with SEGV in
571 test_re and test_sre due to the small default stack size. If
572 you set the stack size to 2048 before doing a "make test" the
573 failure can be avoided. If you're using the tcsh (the default
574 on OSX), or csh shells use "limit stacksize 2048" and for the
575 bash shell, use "ulimit -s 2048".
577 On naked Darwin you may want to add the configure option
578 "--disable-toolbox-glue" to disable the glue code for the Carbon
579 interface modules. The modules themselves are currently only built
580 if you add the --enable-framework option, see below.
582 On a clean OSX /usr/local does not exist. Do a
583 "sudo mkdir -m 775 /usr/local"
584 before you do a make install. It is probably not a good idea to
585 do "sudo make install" which installs everything as superuser,
586 as this may later cause problems when installing distutils-based
589 Some people have reported problems building Python after using "fink"
590 to install additional unix software. Disabling fink (remove all
591 references to /sw from your .profile or .login) should solve this.
593 You may want to try the configure option "--enable-framework"
594 which installs Python as a framework. The location can be set
595 as argument to the --enable-framework option (default
596 /Library/Frameworks). A framework install is probably needed if you
597 want to use any Aqua-based GUI toolkit (whether Tkinter, wxPython,
598 Carbon, Cocoa or anything else).
600 You may also want to try the configure option "--enable-universalsdk"
601 which builds Python as a universal binary with support for the
602 i386 and PPC architetures. This requires Xcode 2.1 or later to build.
604 See Mac/OSX/README for more information on framework and
607 Cygwin: With recent (relative to the time of writing, 2001-12-19)
608 Cygwin installations, there are problems with the interaction
609 of dynamic linking and fork(). This manifests itself in build
610 failures during the execution of setup.py.
612 There are two workarounds that both enable Python (albeit
613 without threading support) to build and pass all tests on
614 NT/2000 (and most likely XP as well, though reports of testing
615 on XP would be appreciated).
619 (a) the band-aid fix is to link the _socket module statically
620 rather than dynamically (which is the default).
622 To do this, run "./configure --with-threads=no" including any
623 other options you need (--prefix, etc.). Then in Modules/Setup
627 #_socket socketmodule.c \
628 # -DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \
629 # -L$(SSL)/lib -lssl -lcrypto
631 and remove "local/" from the SSL variable. Finally, just run
634 (b) The "proper" fix is to rebase the Cygwin DLLs to prevent
635 base address conflicts. Details on how to do this can be
636 found in the following mail:
638 http://sources.redhat.com/ml/cygwin/2001-12/msg00894.html
640 It is hoped that a version of this solution will be
641 incorporated into the Cygwin distribution fairly soon.
643 Two additional problems:
645 (1) Threading support should still be disabled due to a known
646 bug in Cygwin pthreads that causes test_threadedtempfile to
649 (2) The _curses module does not build. This is a known
650 Cygwin ncurses problem that should be resolved the next time
651 that this package is released.
653 On older versions of Cygwin, test_poll may hang and test_strftime
656 The situation on 9X/Me is not accurately known at present.
657 Some time ago, there were reports that the following
658 regression tests failed:
664 Due to the test_select hang on 9X/Me, one should run the
665 regression test using the following:
667 make TESTOPTS='-l -x test_select' test
669 News regarding these platforms with more recent Cygwin
670 versions would be appreciated!
672 AtheOS: From Octavian Cerna <tavy at ylabs.com>:
676 Make sure you have shared versions of the libraries you
677 want to use with Python. You will have to compile them
678 yourself, or download precompiled packages.
680 Recommended libraries:
688 $ ./configure --prefix=/usr/python
691 Python is always built as a shared library, otherwise
692 dynamic loading would not work.
701 # pkgmanager -a /usr/python
706 - large file support: due to a stdio bug in glibc/libio,
707 access to large files may not work correctly. fseeko()
708 tries to seek to a negative offset. ftello() returns a
709 negative offset, it looks like a 32->64bit
710 sign-extension issue. The lowlevel functions (open,
712 - sockets: AF_UNIX is defined in the C library and in
713 Python, but not implemented in the system.
714 - select: poll is available in the C library, but does not
715 work (It does not return POLLNVAL for bad fds and
717 - posix: statvfs and fstatvfs always return ENOSYS.
719 - mmap: not yet implemented in AtheOS
720 - nis: broken (on an unconfigured system
721 yp_get_default_domain() returns junk instead of
723 - dl: dynamic loading doesn't work via dlopen()
724 - resource: getrimit and setrlimit are not yet
727 - if you are getting segmentation faults, you probably are
728 low on memory. AtheOS doesn't handle very well an
729 out-of-memory condition and simply SEGVs the process.
739 Configuring the bsddb and dbm modules
740 -------------------------------------
742 Beginning with Python version 2.3, the PyBsddb package
743 <http://pybsddb.sf.net/> was adopted into Python as the bsddb package,
744 exposing a set of package-level functions which provide
745 backwards-compatible behavior. Only versions 3.3 through 4.4 of
746 Sleepycat's libraries provide the necessary API, so older versions
747 aren't supported through this interface. The old bsddb module has
748 been retained as bsddb185, though it is not built by default. Users
749 wishing to use it will have to tweak Modules/Setup to build it. The
750 dbm module will still be built against the Sleepycat libraries if
751 other preferred alternatives (ndbm, gdbm) are not found.
753 Building the sqlite3 module
754 ---------------------------
756 To build the sqlite3 module, you'll need the sqlite3 or libsqlite3
757 packages installed, including the header files. Many modern operating
758 systems distribute the headers in a separate package to the library -
759 often it will be the same name as the main package, but with a -dev or
762 The version of pysqlite2 that's including in Python needs sqlite3 3.0.8
763 or later. setup.py attempts to check that it can find a correct version.
768 As of Python 2.0, threads are enabled by default. If you wish to
769 compile without threads, or if your thread support is broken, pass the
770 --with-threads=no switch to configure. Unfortunately, on some
771 platforms, additional compiler and/or linker options are required for
772 threads to work properly. Below is a table of those options,
773 collected by Bill Janssen. We would love to automate this process
774 more, but the information below is not enough to write a patch for the
775 configure.in file, so manual intervention is required. If you patch
776 the configure.in file and are confident that the patch works, please
777 send in the patch. (Don't bother patching the configure script itself
778 -- it is regenerated each time the configure.in file changes.)
780 Compiler switches for threads
781 .............................
783 The definition of _REENTRANT should be configured automatically, if
784 that does not work on your system, or if _REENTRANT is defined
785 incorrectly, please report that as a bug.
787 OS/Compiler/threads Switches for use with threads
788 (POSIX is draft 10, DCE is draft 4) compile & link
790 SunOS 5.{1-5}/{gcc,SunPro cc}/solaris -mt
791 SunOS 5.5/{gcc,SunPro cc}/POSIX (nothing)
792 DEC OSF/1 3.x/cc/DCE -threads
793 (butenhof@zko.dec.com)
794 Digital UNIX 4.x/cc/DCE -threads
795 (butenhof@zko.dec.com)
796 Digital UNIX 4.x/cc/POSIX -pthread
797 (butenhof@zko.dec.com)
798 AIX 4.1.4/cc_r/d7 (nothing)
800 AIX 4.1.4/cc_r4/DCE (nothing)
802 IRIX 6.2/cc/POSIX (nothing)
806 Linker (ld) libraries and flags for threads
807 ...........................................
809 OS/threads Libraries/switches for use with threads
811 SunOS 5.{1-5}/solaris -lthread
812 SunOS 5.5/POSIX -lpthread
813 DEC OSF/1 3.x/DCE -lpthreads -lmach -lc_r -lc
814 (butenhof@zko.dec.com)
815 Digital UNIX 4.x/DCE -lpthreads -lpthread -lmach -lexc -lc
816 (butenhof@zko.dec.com)
817 Digital UNIX 4.x/POSIX -lpthread -lmach -lexc -lc
818 (butenhof@zko.dec.com)
819 AIX 4.1.4/{draft7,DCE} (nothing)
821 IRIX 6.2/POSIX -lpthread
822 (jph@emilia.engr.sgi.com)
825 Building a shared libpython
826 ---------------------------
828 Starting with Python 2.3, the majority of the interpreter can be built
829 into a shared library, which can then be used by the interpreter
830 executable, and by applications embedding Python. To enable this feature,
831 configure with --enable-shared.
833 If you enable this feature, the same object files will be used to create
834 a static library. In particular, the static library will contain object
835 files using position-independent code (PIC) on platforms where PIC flags
836 are needed for the shared library.
839 Configuring additional built-in modules
840 ---------------------------------------
842 Starting with Python 2.1, the setup.py script at the top of the source
843 distribution attempts to detect which modules can be built and
844 automatically compiles them. Autodetection doesn't always work, so
845 you can still customize the configuration by editing the Modules/Setup
846 file; but this should be considered a last resort. The rest of this
847 section only applies if you decide to edit the Modules/Setup file.
848 You also need this to enable static linking of certain modules (which
849 is needed to enable profiling on some systems).
851 This file is initially copied from Setup.dist by the configure script;
852 if it does not exist yet, create it by copying Modules/Setup.dist
853 yourself (configure will never overwrite it). Never edit Setup.dist
854 -- always edit Setup or Setup.local (see below). Read the comments in
855 the file for information on what kind of edits are allowed. When you
856 have edited Setup in the Modules directory, the interpreter will
857 automatically be rebuilt the next time you run make (in the toplevel
860 Many useful modules can be built on any Unix system, but some optional
861 modules can't be reliably autodetected. Often the quickest way to
862 determine whether a particular module works or not is to see if it
863 will build: enable it in Setup, then if you get compilation or link
864 errors, disable it -- you're either missing support or need to adjust
865 the compilation and linking parameters for that module.
867 On SGI IRIX, there are modules that interface to many SGI specific
868 system libraries, e.g. the GL library and the audio hardware. These
869 modules will not be built by the setup.py script.
871 In addition to the file Setup, you can also edit the file Setup.local.
872 (the makesetup script processes both). You may find it more
873 convenient to edit Setup.local and leave Setup alone. Then, when
874 installing a new Python version, you can copy your old Setup.local
878 Setting the optimization/debugging options
879 ------------------------------------------
881 If you want or need to change the optimization/debugging options for
882 the C compiler, assign to the OPT variable on the toplevel make
883 command; e.g. "make OPT=-g" will build a debugging version of Python
884 on most platforms. The default is OPT=-O; a value for OPT in the
885 environment when the configure script is run overrides this default
886 (likewise for CC; and the initial value for LIBS is used as the base
887 set of libraries to link with).
889 When compiling with GCC, the default value of OPT will also include
890 the -Wall and -Wstrict-prototypes options.
892 Additional debugging code to help debug memory management problems can
893 be enabled by using the --with-pydebug option to the configure script.
895 For flags that change binary compatibility, use the EXTRA_CFLAGS
902 If you want C profiling turned on, the easiest way is to run configure
903 with the CC environment variable to the necessary compiler
904 invocation. For example, on Linux, this works for profiling using
907 CC="gcc -pg" ./configure
909 Note that on Linux, gprof apparently does not work for shared
910 libraries. The Makefile/Setup mechanism can be used to compile and
911 link most extension modules statically.
917 To test the interpreter, type "make test" in the top-level directory.
918 This runs the test set twice (once with no compiled files, once with
919 the compiled files left by the previous test run). The test set
920 produces some output. You can generally ignore the messages about
921 skipped tests due to optional features which can't be imported.
922 If a message is printed about a failed test or a traceback or core
923 dump is produced, something is wrong. On some Linux systems (those
924 that are not yet using glibc 6), test_strftime fails due to a
925 non-standard implementation of strftime() in the C library. Please
926 ignore this, or upgrade to glibc version 6.
928 IMPORTANT: If the tests fail and you decide to mail a bug report,
929 *don't* include the output of "make test". It is useless. Run the
930 failing test manually, as follows:
932 ./python ./Lib/test/test_whatever.py
934 (substituting the top of the source tree for '.' if you built in a
935 different directory). This runs the test in verbose mode.
941 To install the Python binary, library modules, shared library modules
942 (see below), include files, configuration files, and the manual page,
947 This will install all platform-independent files in subdirectories of
948 the directory given with the --prefix option to configure or to the
949 `prefix' Make variable (default /usr/local). All binary and other
950 platform-specific files will be installed in subdirectories if the
951 directory given by --exec-prefix or the `exec_prefix' Make variable
952 (defaults to the --prefix directory) is given.
954 If DESTDIR is set, it will be taken as the root directory of the
955 installation, and files will be installed into $(DESTDIR)$(prefix),
956 $(DESTDIR)$(exec_prefix), etc.
958 All subdirectories created will have Python's version number in their
959 name, e.g. the library modules are installed in
960 "/usr/local/lib/python<version>/" by default, where <version> is the
961 <major>.<minor> release number (e.g. "2.1"). The Python binary is
962 installed as "python<version>" and a hard link named "python" is
963 created. The only file not installed with a version number in its
964 name is the manual page, installed as "/usr/local/man/man1/python.1"
967 If you have a previous installation of Python that you don't
968 want to replace yet, use
972 This installs the same set of files as "make install" except it
973 doesn't create the hard link to "python<version>" named "python" and
974 it doesn't install the manual page at all.
976 The only thing you may have to install manually is the Python mode for
977 Emacs found in Misc/python-mode.el. (But then again, more recent
978 versions of Emacs may already have it.) Follow the instructions that
979 came with Emacs for installation of site-specific files.
981 On Mac OS X, if you have configured Python with --enable-framework, you
982 should use "make frameworkinstall" to do the installation. Note that this
983 installs the Python executable in a place that is not normally on your
984 PATH, you may want to set up a symlink in /usr/local/bin.
987 Configuration options and variables
988 -----------------------------------
990 Some special cases are handled by passing options to the configure
993 WARNING: if you rerun the configure script with different options, you
994 must run "make clean" before rebuilding. Exceptions to this rule:
995 after changing --prefix or --exec-prefix, all you need to do is remove
998 --with(out)-gcc: The configure script uses gcc (the GNU C compiler) if
999 it finds it. If you don't want this, or if this compiler is
1000 installed but broken on your platform, pass the option
1001 --without-gcc. You can also pass "CC=cc" (or whatever the
1002 name of the proper C compiler is) in the environment, but the
1003 advantage of using --without-gcc is that this option is
1004 remembered by the config.status script for its --recheck
1007 --prefix, --exec-prefix: If you want to install the binaries and the
1008 Python library somewhere else than in /usr/local/{bin,lib},
1009 you can pass the option --prefix=DIRECTORY; the interpreter
1010 binary will be installed as DIRECTORY/bin/python and the
1011 library files as DIRECTORY/lib/python/*. If you pass
1012 --exec-prefix=DIRECTORY (as well) this overrides the
1013 installation prefix for architecture-dependent files (like the
1014 interpreter binary). Note that --prefix=DIRECTORY also
1015 affects the default module search path (sys.path), when
1016 Modules/config.c is compiled. Passing make the option
1017 prefix=DIRECTORY (and/or exec_prefix=DIRECTORY) overrides the
1018 prefix set at configuration time; this may be more convenient
1019 than re-running the configure script if you change your mind
1020 about the install prefix.
1022 --with-readline: This option is no longer supported. GNU
1023 readline is automatically enabled by setup.py when present.
1025 --with-threads: On most Unix systems, you can now use multiple
1026 threads, and support for this is enabled by default. To
1027 disable this, pass --with-threads=no. If the library required
1028 for threads lives in a peculiar place, you can use
1029 --with-thread=DIRECTORY. IMPORTANT: run "make clean" after
1030 changing (either enabling or disabling) this option, or you
1031 will get link errors! Note: for DEC Unix use
1032 --with-dec-threads instead.
1034 --with-sgi-dl: On SGI IRIX 4, dynamic loading of extension modules is
1035 supported by the "dl" library by Jack Jansen, which is
1036 ftp'able from ftp://ftp.cwi.nl/pub/dynload/dl-1.6.tar.Z.
1037 This is enabled (after you've ftp'ed and compiled the dl
1038 library) by passing --with-sgi-dl=DIRECTORY where DIRECTORY
1039 is the absolute pathname of the dl library. (Don't bother on
1040 IRIX 5, it already has dynamic linking using SunOS style
1041 shared libraries.) THIS OPTION IS UNSUPPORTED.
1043 --with-dl-dld: Dynamic loading of modules is rumored to be supported
1044 on some other systems: VAX (Ultrix), Sun3 (SunOS 3.4), Sequent
1045 Symmetry (Dynix), and Atari ST. This is done using a
1046 combination of the GNU dynamic loading package
1047 (ftp://ftp.cwi.nl/pub/dynload/dl-dld-1.1.tar.Z) and an
1048 emulation of the SGI dl library mentioned above (the emulation
1050 ftp://ftp.cwi.nl/pub/dynload/dld-3.2.3.tar.Z). To
1051 enable this, ftp and compile both libraries, then call
1052 configure, passing it the option
1053 --with-dl-dld=DL_DIRECTORY,DLD_DIRECTORY where DL_DIRECTORY is
1054 the absolute pathname of the dl emulation library and
1055 DLD_DIRECTORY is the absolute pathname of the GNU dld library.
1056 (Don't bother on SunOS 4 or 5, they already have dynamic
1057 linking using shared libraries.) THIS OPTION IS UNSUPPORTED.
1059 --with-libm, --with-libc: It is possible to specify alternative
1060 versions for the Math library (default -lm) and the C library
1061 (default the empty string) using the options
1062 --with-libm=STRING and --with-libc=STRING, respectively. For
1063 example, if your system requires that you pass -lc_s to the C
1064 compiler to use the shared C library, you can pass
1065 --with-libc=-lc_s. These libraries are passed after all other
1066 libraries, the C library last.
1068 --with-libs='libs': Add 'libs' to the LIBS that the python interpreter
1071 --with-cxx-main=<compiler>: If you plan to use C++ extension modules,
1072 then -- on some platforms -- you need to compile python's main()
1073 function with the C++ compiler. With this option, make will use
1074 <compiler> to compile main() *and* to link the python executable.
1075 It is likely that the resulting executable depends on the C++
1076 runtime library of <compiler>. (The default is --without-cxx-main.)
1078 There are platforms that do not require you to build Python
1079 with a C++ compiler in order to use C++ extension modules.
1080 E.g., x86 Linux with ELF shared binaries and GCC 3.x, 4.x is such
1081 a platform. We recommend that you configure Python
1082 --without-cxx-main on those platforms because a mismatch
1083 between the C++ compiler version used to build Python and to
1084 build a C++ extension module is likely to cause a crash at
1087 The Python installation also stores the variable CXX that
1088 determines, e.g., the C++ compiler distutils calls by default
1089 to build C++ extensions. If you set CXX on the configure command
1090 line to any string of non-zero length, then configure won't
1091 change CXX. If you do not preset CXX but pass
1092 --with-cxx-main=<compiler>, then configure sets CXX=<compiler>.
1093 In all other cases, configure looks for a C++ compiler by
1094 some common names (c++, g++, gcc, CC, cxx, cc++, cl) and sets
1095 CXX to the first compiler it finds. If it does not find any
1096 C++ compiler, then it sets CXX="".
1098 Similarly, if you want to change the command used to link the
1099 python executable, then set LINKCC on the configure command line.
1102 --with-pydebug: Enable additional debugging code to help track down
1103 memory management problems. This allows printing a list of all
1104 live objects when the interpreter terminates.
1106 --with(out)-universal-newlines: enable reading of text files with
1107 foreign newline convention (default: enabled). In other words,
1108 any of \r, \n or \r\n is acceptable as end-of-line character.
1109 If enabled import and execfile will automatically accept any newline
1110 in files. Python code can open a file with open(file, 'U') to
1111 read it in universal newline mode. THIS OPTION IS UNSUPPORTED.
1113 --with-tsc: Profile using the Pentium timestamping counter (TSC).
1115 --with-system-ffi: Build the _ctypes extension module using an ffi
1116 library installed on the system.
1119 Building for multiple architectures (using the VPATH feature)
1120 -------------------------------------------------------------
1122 If your file system is shared between multiple architectures, it
1123 usually is not necessary to make copies of the sources for each
1124 architecture you want to support. If the make program supports the
1125 VPATH feature, you can create an empty build directory for each
1126 architecture, and in each directory run the configure script (on the
1127 appropriate machine with the appropriate options). This creates the
1128 necessary subdirectories and the Makefiles therein. The Makefiles
1129 contain a line VPATH=... which points to a directory containing the
1130 actual sources. (On SGI systems, use "smake -J1" instead of "make" if
1131 you use VPATH -- don't try gnumake.)
1133 For example, the following is all you need to build a minimal Python
1134 in /usr/tmp/python (assuming ~guido/src/python is the toplevel
1135 directory and you want to build in /usr/tmp/python):
1137 $ mkdir /usr/tmp/python
1138 $ cd /usr/tmp/python
1139 $ ~guido/src/python/configure
1145 Note that configure copies the original Setup file to the build
1146 directory if it finds no Setup file there. This means that you can
1147 edit the Setup file for each architecture independently. For this
1148 reason, subsequent changes to the original Setup file are not tracked
1149 automatically, as they might overwrite local changes. To force a copy
1150 of a changed original Setup file, delete the target Setup file. (The
1151 makesetup script supports multiple input files, so if you want to be
1152 fancy you can change the rules to create an empty Setup.local if it
1153 doesn't exist and run it with arguments $(srcdir)/Setup Setup.local;
1154 however this assumes that you only need to add modules.)
1157 Building on non-UNIX systems
1158 ----------------------------
1160 For Windows (2000/NT/ME/98/95), assuming you have MS VC++ 7.1, the
1161 project files are in PCbuild, the workspace is pcbuild.dsw. See
1162 PCbuild\readme.txt for detailed instructions.
1164 For other non-Unix Windows compilers, in particular MS VC++ 6.0 and
1165 for OS/2, enter the directory "PC" and read the file "readme.txt".
1167 For the Mac, a separate source distribution will be made available,
1168 for use with the CodeWarrior compiler. If you are interested in Mac
1169 development, join the PythonMac Special Interest Group
1170 (http://www.python.org/sigs/pythonmac-sig/, or send email to
1171 pythonmac-sig-request@python.org).
1173 Of course, there are also binary distributions available for these
1174 platforms -- see http://www.python.org/.
1176 To port Python to a new non-UNIX system, you will have to fake the
1177 effect of running the configure script manually (for Mac and PC, this
1178 has already been done for you). A good start is to copy the file
1179 pyconfig.h.in to pyconfig.h and edit the latter to reflect the actual
1180 configuration of your system. Most symbols must simply be defined as
1181 1 only if the corresponding feature is present and can be left alone
1182 otherwise; however the *_t type symbols must be defined as some
1183 variant of int if they need to be defined at all.
1185 For all platforms, it's important that the build arrange to define the
1186 preprocessor symbol NDEBUG on the compiler command line in a release
1187 build of Python (else assert() calls remain in the code, hurting
1188 release-build performance). The Unix, Windows and Mac builds already
1192 Miscellaneous issues
1193 ====================
1198 There's an excellent Emacs editing mode for Python code; see the file
1199 Misc/python-mode.el. Originally written by the famous Tim Peters, it
1200 is now maintained by the equally famous Barry Warsaw (it's no
1201 coincidence that they now both work on the same team). The latest
1202 version, along with various other contributed Python-related Emacs
1203 goodies, is online at http://www.python.org/emacs/python-mode. And
1204 if you are planning to edit the Python C code, please pick up the
1205 latest version of CC Mode http://www.python.org/emacs/cc-mode; it
1206 contains a "python" style used throughout most of the Python C source
1207 files. (Newer versions of Emacs or XEmacs may already come with the
1208 latest version of python-mode.)
1214 The setup.py script automatically configures this when it detects a
1215 usable Tcl/Tk installation. This requires Tcl/Tk version 8.0 or
1218 For more Tkinter information, see the Tkinter Resource page:
1219 http://www.python.org/topics/tkinter/
1221 There are demos in the Demo/tkinter directory.
1223 Note that there's a Python module called "Tkinter" (capital T) which
1224 lives in Lib/lib-tk/Tkinter.py, and a C module called "_tkinter"
1225 (lower case t and leading underscore) which lives in
1226 Modules/_tkinter.c. Demos and normal Tk applications import only the
1227 Python Tkinter module -- only the latter imports the C _tkinter
1228 module. In order to find the C _tkinter module, it must be compiled
1229 and linked into the Python interpreter -- the setup.py script does
1230 this. In order to find the Python Tkinter module, sys.path must be
1231 set correctly -- normal installation takes care of this.
1234 Distribution structure
1235 ----------------------
1237 Most subdirectories have their own README files. Most files have
1240 BeOS/ Files specific to the BeOS port
1241 Demo/ Demonstration scripts, modules and programs
1242 Doc/ Documentation sources (LaTeX)
1243 Grammar/ Input for the parser generator
1244 Include/ Public header files
1245 LICENSE Licensing information
1246 Lib/ Python library modules
1247 Mac/ Macintosh specific resources
1248 Makefile.pre.in Source from which config.status creates the Makefile.pre
1249 Misc/ Miscellaneous useful files
1250 Modules/ Implementation of most built-in modules
1251 Objects/ Implementation of most built-in object types
1252 PC/ Files specific to PC ports (DOS, Windows, OS/2)
1253 PCbuild/ Build directory for Microsoft Visual C++
1254 Parser/ The parser and tokenizer and their input handling
1255 Python/ The byte-compiler and interpreter
1256 README The file you're reading now
1257 Tools/ Some useful programs written in Python
1258 pyconfig.h.in Source from which pyconfig.h is created (GNU autoheader output)
1259 configure Configuration shell script (GNU autoconf output)
1260 configure.in Configuration specification (input for GNU autoconf)
1261 install-sh Shell script used to install files
1262 setup.py Python script used to build extension modules
1264 The following files will (may) be created in the toplevel directory by
1265 the configuration and build processes:
1267 Makefile Build rules
1268 Makefile.pre Build rules before running Modules/makesetup
1269 buildno Keeps track of the build number
1270 config.cache Cache of configuration variables
1271 pyconfig.h Configuration header
1272 config.log Log from last configure run
1273 config.status Status from last run of the configure script
1274 getbuildinfo.o Object file from Modules/getbuildinfo.c
1275 libpython<version>.a The library archive
1276 python The executable interpreter
1277 tags, TAGS Tags files for vi and Emacs
1284 --Guido van Rossum (home page: http://www.python.org/~guido/)