1 This is Python version 2.5
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!)
285 GCC 4.2: There is a known incompatibility between Python and GCC,
286 where GCC 4.1 and later uses an interpretation of C
287 different to earlier GCC releases in an area where the C
288 specification has undefined behaviour (namely, integer arithmetic
289 involving -sys.maxint-1).
291 As a consequence, compiling Python with GCC 4.1/4.2 is not
292 recommended. It is likely that this problem will be resolved
293 in future Python releases. As a work-around, it seems that
294 adding -fwrapv to the compiler options restores the earlier
297 Unix platforms: If your vendor still ships (and you still use) Berkeley DB
298 1.85 you will need to edit Modules/Setup to build the bsddb185
299 module and add a line to sitecustomize.py which makes it the
300 default. In Modules/Setup a line like
302 bsddb185 bsddbmodule.c
304 should work. (You may need to add -I, -L or -l flags to direct the
305 compiler and linker to your include files and libraries.)
307 XXX I think this next bit is out of date:
309 64-bit platforms: The modules audioop, imageop and rgbimg don't work.
310 The setup.py script disables them on 64-bit installations.
311 Don't try to enable them in the Modules/Setup file. They
312 contain code that is quite wordsize sensitive. (If you have a
315 Solaris: When using Sun's C compiler with threads, at least on Solaris
316 2.5.1, you need to add the "-mt" compiler option (the simplest
317 way is probably to specify the compiler with this option as
318 the "CC" environment variable when running the configure
321 When using GCC on Solaris, beware of binutils 2.13 or GCC
322 versions built using it. This mistakenly enables the
323 -zcombreloc option which creates broken shared libraries on
324 Solaris. binutils 2.12 works, and the binutils maintainers
325 are aware of the problem. Binutils 2.13.1 only partially
326 fixed things. It appears that 2.13.2 solves the problem
327 completely. This problem is known to occur with Solaris 2.7
328 and 2.8, but may also affect earlier and later versions of the
331 When the dynamic loader complains about errors finding shared
334 ld.so.1: ./python: fatal: libstdc++.so.5: open failed:
335 No such file or directory
337 you need to first make sure that the library is available on
338 your system. Then, you need to instruct the dynamic loader how
339 to find it. You can choose any of the following strategies:
341 1. When compiling Python, set LD_RUN_PATH to the directories
342 containing missing libraries.
343 2. When running Python, set LD_LIBRARY_PATH to these directories.
344 3. Use crle(8) to extend the search path of the loader.
345 4. Modify the installed GCC specs file, adding -R options into the
348 The complex object fails to compile on Solaris 10 with gcc 3.4 (at
349 least up to 3.4.3). To work around it, define Py_HUGE_VAL as
352 make CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()" -I. -I$(srcdir)/Include'
353 ./python setup.py CPPFLAGS='-D"Py_HUGE_VAL=HUGE_VAL()"'
355 Linux: A problem with threads and fork() was tracked down to a bug in
356 the pthreads code in glibc version 2.0.5; glibc version 2.0.7
357 solves the problem. This causes the popen2 test to fail;
358 problem and solution reported by Pablo Bleyer.
360 Red Hat Linux: Red Hat 9 built Python2.2 in UCS-4 mode and hacked
361 Tcl to support it. To compile Python2.3 with Tkinter, you will
362 need to pass --enable-unicode=ucs4 flag to ./configure.
364 There's an executable /usr/bin/python which is Python
365 1.5.2 on most older Red Hat installations; several key Red Hat tools
366 require this version. Python 2.1.x may be installed as
367 /usr/bin/python2. The Makefile installs Python as
368 /usr/local/bin/python, which may or may not take precedence
369 over /usr/bin/python, depending on how you have set up $PATH.
371 FreeBSD 3.x and probably platforms with NCurses that use libmytinfo or
372 similar: When using cursesmodule, the linking is not done in
373 the correct order with the defaults. Remove "-ltermcap" from
374 the readline entry in Setup, and use as curses entry: "curses
375 cursesmodule.c -lmytinfo -lncurses -ltermcap" - "mytinfo" (so
376 called on FreeBSD) should be the name of the auxiliary library
377 required on your platform. Normally, it would be linked
378 automatically, but not necessarily in the correct order.
380 BSDI: BSDI versions before 4.1 have known problems with threads,
381 which can cause strange errors in a number of modules (for
382 instance, the 'test_signal' test script will hang forever.)
383 Turning off threads (with --with-threads=no) or upgrading to
384 BSDI 4.1 solves this problem.
386 DEC Unix: Run configure with --with-dec-threads, or with
387 --with-threads=no if no threads are desired (threads are on by
388 default). When using GCC, it is possible to get an internal
389 compiler error if optimization is used. This was reported for
390 GCC 2.7.2.3 on selectmodule.c. Manually compile the affected
391 file without optimization to solve the problem.
393 DEC Ultrix: compile with GCC to avoid bugs in the native compiler,
394 and pass SHELL=/bin/sh5 to Make when installing.
396 AIX: A complete overhaul of the shared library support is now in
397 place. See Misc/AIX-NOTES for some notes on how it's done.
398 (The optimizer bug reported at this place in previous releases
399 has been worked around by a minimal code change.) If you get
400 errors about pthread_* functions, during compile or during
401 testing, try setting CC to a thread-safe (reentrant) compiler,
402 like "cc_r". For full C++ module support, set CC="xlC_r" (or
403 CC="xlC" without thread support).
405 AIX 5.3: To build a 64-bit version with IBM's compiler, I used the
408 export PATH=/usr/bin:/usr/vacpp/bin
409 ./configure --with-gcc="xlc_r -q64" --with-cxx="xlC_r -q64" \
410 --disable-ipv6 AR="ar -X64"
413 HP-UX: When using threading, you may have to add -D_REENTRANT to the
414 OPT variable in the top-level Makefile; reported by Pat Knight,
415 this seems to make a difference (at least for HP-UX 10.20)
416 even though pyconfig.h defines it. This seems unnecessary when
417 using HP/UX 11 and later - threading seems to work "out of the
420 HP-UX ia64: When building on the ia64 (Itanium) platform using HP's
421 compiler, some experience has shown that the compiler's
422 optimiser produces a completely broken version of python
423 (see http://www.python.org/sf/814976). To work around this,
424 edit the Makefile and remove -O from the OPT line.
426 To build a 64-bit executable on an Itanium 2 system using HP's
427 compiler, use these environment variables:
432 LDFLAGS="+DD64 -lxnet"
434 and call configure as:
436 ./configure --without-gcc
438 then *unset* the environment variables again before running
439 make. (At least one of these flags causes the build to fail
440 if it remains set.) You still have to edit the Makefile and
441 remove -O from the OPT line.
443 HP PA-RISC 2.0: A recent bug report (http://www.python.org/sf/546117)
444 suggests that the C compiler in this 64-bit system has bugs
445 in the optimizer that break Python. Compiling without
446 optimization solves the problems.
448 SCO: The following apply to SCO 3 only; Python builds out of the box
449 on SCO 5 (or so we've heard).
451 1) Everything works much better if you add -U__STDC__ to the
452 defs. This is because all the SCO header files are broken.
453 Anything that isn't mentioned in the C standard is
454 conditionally excluded when __STDC__ is defined.
456 2) Due to the U.S. export restrictions, SCO broke the crypt
457 stuff out into a separate library, libcrypt_i.a so the LIBS
460 LIBS=' -lsocket -lcrypt_i'
462 UnixWare: There are known bugs in the math library of the system, as well as
463 problems in the handling of threads (calling fork in one
464 thread may interrupt system calls in others). Therefore, test_math and
465 tests involving threads will fail until those problems are fixed.
467 QNX: Chris Herborth (chrish@qnx.com) writes:
468 configure works best if you use GNU bash; a port is available on
469 ftp.qnx.com in /usr/free. I used the following process to build,
470 test and install Python 1.5.x under QNX:
472 1) CONFIG_SHELL=/usr/local/bin/bash CC=cc RANLIB=: \
473 ./configure --verbose --without-gcc --with-libm=""
475 2) edit Modules/Setup to activate everything that makes sense for
476 your system... tested here at QNX with the following modules:
478 array, audioop, binascii, cPickle, cStringIO, cmath,
479 crypt, curses, errno, fcntl, gdbm, grp, imageop,
480 _locale, math, md5, new, operator, parser, pcre,
481 posix, pwd, readline, regex, reop, rgbimg, rotor,
482 select, signal, socket, soundex, strop, struct,
483 syslog, termios, time, timing, zlib, audioop, imageop, rgbimg
485 3) make SHELL=/usr/local/bin/bash
487 or, if you feel the need for speed:
489 make SHELL=/usr/local/bin/bash OPT="-5 -Oil+nrt"
491 4) make SHELL=/usr/local/bin/bash test
493 Using GNU readline 2.2 seems to behave strangely, but I
494 think that's a problem with my readline 2.2 port. :-\
496 5) make SHELL=/usr/local/bin/bash install
498 If you get SIGSEGVs while running Python (I haven't yet, but
499 I've only run small programs and the test cases), you're
500 probably running out of stack; the default 32k could be a
501 little tight. To increase the stack size, edit the Makefile
502 to read: LDFLAGS = -N 48k
504 BeOS: See Misc/BeOS-NOTES for notes about compiling/installing
505 Python on BeOS R3 or later. Note that only the PowerPC
506 platform is supported for R3; both PowerPC and x86 are
509 Cray T3E: Mark Hadfield (m.hadfield@niwa.co.nz) writes:
510 Python can be built satisfactorily on a Cray T3E but based on
511 my experience with the NIWA T3E (2002-05-22, version 2.2.1)
512 there are a few bugs and gotchas. For more information see a
513 thread on comp.lang.python in May 2002 entitled "Building
516 1) Use Cray's cc and not gcc. The latter was reported not to
517 work by Konrad Hinsen. It may work now, but it may not.
519 2) To set sys.platform to something sensible, pass the
520 following environment variable to the configure script:
524 2) Run configure with option "--enable-unicode=ucs4".
526 3) The Cray T3E does not support dynamic linking, so extension
527 modules have to be built by adding (or uncommenting) lines
528 in Modules/Setup. The minimum set of modules is
530 posix, new, _sre, unicodedata
532 On NIWA's vanilla T3E system the following have also been
533 included successfully:
535 _codecs, _locale, _socket, _symtable, _testcapi, _weakref
536 array, binascii, cmath, cPickle, crypt, cStringIO, dbm
537 errno, fcntl, grp, math, md5, operator, parser, pcre, pwd
538 regex, rotor, select, struct, strop, syslog, termios
539 time, timing, xreadlines
541 4) Once the python executable and library have been built, make
542 will execute setup.py, which will attempt to build remaining
543 extensions and link them dynamically. Each of these attempts
544 will fail but should not halt the make process. This is
547 5) Running "make test" uses a lot of resources and causes
548 problems on our system. You might want to try running tests
549 singly or in small groups.
551 SGI: SGI's standard "make" utility (/bin/make or /usr/bin/make)
552 does not check whether a command actually changed the file it
553 is supposed to build. This means that whenever you say "make"
554 it will redo the link step. The remedy is to use SGI's much
555 smarter "smake" utility (/usr/sbin/smake), or GNU make. If
556 you set the first line of the Makefile to #!/usr/sbin/smake
557 smake will be invoked by make (likewise for GNU make).
559 WARNING: There are bugs in the optimizer of some versions of
560 SGI's compilers that can cause bus errors or other strange
561 behavior, especially on numerical operations. To avoid this,
562 try building with "make OPT=".
564 OS/2: If you are running Warp3 or Warp4 and have IBM's VisualAge C/C++
565 compiler installed, just change into the pc\os2vacpp directory
566 and type NMAKE. Threading and sockets are supported by default
567 in the resulting binaries of PYTHON15.DLL and PYTHON.EXE.
569 Monterey (64-bit AIX): The current Monterey C compiler (Visual Age)
570 uses the OBJECT_MODE={32|64} environment variable to set the
571 compilation mode to either 32-bit or 64-bit (32-bit mode is
572 the default). Presumably you want 64-bit compilation mode for
573 this 64-bit OS. As a result you must first set OBJECT_MODE=64
574 in your environment before configuring (./configure) or
575 building (make) Python on Monterey.
577 Reliant UNIX: The thread support does not compile on Reliant UNIX, and
578 there is a (minor) problem in the configure script for that
579 platform as well. This should be resolved in time for a
582 MacOSX: The tests will crash on both 10.1 and 10.2 with SEGV in
583 test_re and test_sre due to the small default stack size. If
584 you set the stack size to 2048 before doing a "make test" the
585 failure can be avoided. If you're using the tcsh (the default
586 on OSX), or csh shells use "limit stacksize 2048" and for the
587 bash shell, use "ulimit -s 2048".
589 On naked Darwin you may want to add the configure option
590 "--disable-toolbox-glue" to disable the glue code for the Carbon
591 interface modules. The modules themselves are currently only built
592 if you add the --enable-framework option, see below.
594 On a clean OSX /usr/local does not exist. Do a
595 "sudo mkdir -m 775 /usr/local"
596 before you do a make install. It is probably not a good idea to
597 do "sudo make install" which installs everything as superuser,
598 as this may later cause problems when installing distutils-based
601 Some people have reported problems building Python after using "fink"
602 to install additional unix software. Disabling fink (remove all
603 references to /sw from your .profile or .login) should solve this.
605 You may want to try the configure option "--enable-framework"
606 which installs Python as a framework. The location can be set
607 as argument to the --enable-framework option (default
608 /Library/Frameworks). A framework install is probably needed if you
609 want to use any Aqua-based GUI toolkit (whether Tkinter, wxPython,
610 Carbon, Cocoa or anything else).
612 You may also want to try the configure option "--enable-universalsdk"
613 which builds Python as a universal binary with support for the
614 i386 and PPC architectures. This requires Xcode 2.1 or later to build.
616 See Mac/OSX/README for more information on framework and
619 Cygwin: With recent (relative to the time of writing, 2001-12-19)
620 Cygwin installations, there are problems with the interaction
621 of dynamic linking and fork(). This manifests itself in build
622 failures during the execution of setup.py.
624 There are two workarounds that both enable Python (albeit
625 without threading support) to build and pass all tests on
626 NT/2000 (and most likely XP as well, though reports of testing
627 on XP would be appreciated).
631 (a) the band-aid fix is to link the _socket module statically
632 rather than dynamically (which is the default).
634 To do this, run "./configure --with-threads=no" including any
635 other options you need (--prefix, etc.). Then in Modules/Setup
639 #_socket socketmodule.c \
640 # -DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \
641 # -L$(SSL)/lib -lssl -lcrypto
643 and remove "local/" from the SSL variable. Finally, just run
646 (b) The "proper" fix is to rebase the Cygwin DLLs to prevent
647 base address conflicts. Details on how to do this can be
648 found in the following mail:
650 http://sources.redhat.com/ml/cygwin/2001-12/msg00894.html
652 It is hoped that a version of this solution will be
653 incorporated into the Cygwin distribution fairly soon.
655 Two additional problems:
657 (1) Threading support should still be disabled due to a known
658 bug in Cygwin pthreads that causes test_threadedtempfile to
661 (2) The _curses module does not build. This is a known
662 Cygwin ncurses problem that should be resolved the next time
663 that this package is released.
665 On older versions of Cygwin, test_poll may hang and test_strftime
668 The situation on 9X/Me is not accurately known at present.
669 Some time ago, there were reports that the following
670 regression tests failed:
676 Due to the test_select hang on 9X/Me, one should run the
677 regression test using the following:
679 make TESTOPTS='-l -x test_select' test
681 News regarding these platforms with more recent Cygwin
682 versions would be appreciated!
684 AtheOS: From Octavian Cerna <tavy at ylabs.com>:
688 Make sure you have shared versions of the libraries you
689 want to use with Python. You will have to compile them
690 yourself, or download precompiled packages.
692 Recommended libraries:
700 $ ./configure --prefix=/usr/python
703 Python is always built as a shared library, otherwise
704 dynamic loading would not work.
713 # pkgmanager -a /usr/python
718 - large file support: due to a stdio bug in glibc/libio,
719 access to large files may not work correctly. fseeko()
720 tries to seek to a negative offset. ftello() returns a
721 negative offset, it looks like a 32->64bit
722 sign-extension issue. The lowlevel functions (open,
724 - sockets: AF_UNIX is defined in the C library and in
725 Python, but not implemented in the system.
726 - select: poll is available in the C library, but does not
727 work (It does not return POLLNVAL for bad fds and
729 - posix: statvfs and fstatvfs always return ENOSYS.
731 - mmap: not yet implemented in AtheOS
732 - nis: broken (on an unconfigured system
733 yp_get_default_domain() returns junk instead of
735 - dl: dynamic loading doesn't work via dlopen()
736 - resource: getrimit and setrlimit are not yet
739 - if you are getting segmentation faults, you probably are
740 low on memory. AtheOS doesn't handle very well an
741 out-of-memory condition and simply SEGVs the process.
751 Configuring the bsddb and dbm modules
752 -------------------------------------
754 Beginning with Python version 2.3, the PyBsddb package
755 <http://pybsddb.sf.net/> was adopted into Python as the bsddb package,
756 exposing a set of package-level functions which provide
757 backwards-compatible behavior. Only versions 3.3 through 4.4 of
758 Sleepycat's libraries provide the necessary API, so older versions
759 aren't supported through this interface. The old bsddb module has
760 been retained as bsddb185, though it is not built by default. Users
761 wishing to use it will have to tweak Modules/Setup to build it. The
762 dbm module will still be built against the Sleepycat libraries if
763 other preferred alternatives (ndbm, gdbm) are not found.
765 Building the sqlite3 module
766 ---------------------------
768 To build the sqlite3 module, you'll need the sqlite3 or libsqlite3
769 packages installed, including the header files. Many modern operating
770 systems distribute the headers in a separate package to the library -
771 often it will be the same name as the main package, but with a -dev or
774 The version of pysqlite2 that's including in Python needs sqlite3 3.0.8
775 or later. setup.py attempts to check that it can find a correct version.
780 As of Python 2.0, threads are enabled by default. If you wish to
781 compile without threads, or if your thread support is broken, pass the
782 --with-threads=no switch to configure. Unfortunately, on some
783 platforms, additional compiler and/or linker options are required for
784 threads to work properly. Below is a table of those options,
785 collected by Bill Janssen. We would love to automate this process
786 more, but the information below is not enough to write a patch for the
787 configure.in file, so manual intervention is required. If you patch
788 the configure.in file and are confident that the patch works, please
789 send in the patch. (Don't bother patching the configure script itself
790 -- it is regenerated each time the configure.in file changes.)
792 Compiler switches for threads
793 .............................
795 The definition of _REENTRANT should be configured automatically, if
796 that does not work on your system, or if _REENTRANT is defined
797 incorrectly, please report that as a bug.
799 OS/Compiler/threads Switches for use with threads
800 (POSIX is draft 10, DCE is draft 4) compile & link
802 SunOS 5.{1-5}/{gcc,SunPro cc}/solaris -mt
803 SunOS 5.5/{gcc,SunPro cc}/POSIX (nothing)
804 DEC OSF/1 3.x/cc/DCE -threads
805 (butenhof@zko.dec.com)
806 Digital UNIX 4.x/cc/DCE -threads
807 (butenhof@zko.dec.com)
808 Digital UNIX 4.x/cc/POSIX -pthread
809 (butenhof@zko.dec.com)
810 AIX 4.1.4/cc_r/d7 (nothing)
812 AIX 4.1.4/cc_r4/DCE (nothing)
814 IRIX 6.2/cc/POSIX (nothing)
818 Linker (ld) libraries and flags for threads
819 ...........................................
821 OS/threads Libraries/switches for use with threads
823 SunOS 5.{1-5}/solaris -lthread
824 SunOS 5.5/POSIX -lpthread
825 DEC OSF/1 3.x/DCE -lpthreads -lmach -lc_r -lc
826 (butenhof@zko.dec.com)
827 Digital UNIX 4.x/DCE -lpthreads -lpthread -lmach -lexc -lc
828 (butenhof@zko.dec.com)
829 Digital UNIX 4.x/POSIX -lpthread -lmach -lexc -lc
830 (butenhof@zko.dec.com)
831 AIX 4.1.4/{draft7,DCE} (nothing)
833 IRIX 6.2/POSIX -lpthread
834 (jph@emilia.engr.sgi.com)
837 Building a shared libpython
838 ---------------------------
840 Starting with Python 2.3, the majority of the interpreter can be built
841 into a shared library, which can then be used by the interpreter
842 executable, and by applications embedding Python. To enable this feature,
843 configure with --enable-shared.
845 If you enable this feature, the same object files will be used to create
846 a static library. In particular, the static library will contain object
847 files using position-independent code (PIC) on platforms where PIC flags
848 are needed for the shared library.
851 Configuring additional built-in modules
852 ---------------------------------------
854 Starting with Python 2.1, the setup.py script at the top of the source
855 distribution attempts to detect which modules can be built and
856 automatically compiles them. Autodetection doesn't always work, so
857 you can still customize the configuration by editing the Modules/Setup
858 file; but this should be considered a last resort. The rest of this
859 section only applies if you decide to edit the Modules/Setup file.
860 You also need this to enable static linking of certain modules (which
861 is needed to enable profiling on some systems).
863 This file is initially copied from Setup.dist by the configure script;
864 if it does not exist yet, create it by copying Modules/Setup.dist
865 yourself (configure will never overwrite it). Never edit Setup.dist
866 -- always edit Setup or Setup.local (see below). Read the comments in
867 the file for information on what kind of edits are allowed. When you
868 have edited Setup in the Modules directory, the interpreter will
869 automatically be rebuilt the next time you run make (in the toplevel
872 Many useful modules can be built on any Unix system, but some optional
873 modules can't be reliably autodetected. Often the quickest way to
874 determine whether a particular module works or not is to see if it
875 will build: enable it in Setup, then if you get compilation or link
876 errors, disable it -- you're either missing support or need to adjust
877 the compilation and linking parameters for that module.
879 On SGI IRIX, there are modules that interface to many SGI specific
880 system libraries, e.g. the GL library and the audio hardware. These
881 modules will not be built by the setup.py script.
883 In addition to the file Setup, you can also edit the file Setup.local.
884 (the makesetup script processes both). You may find it more
885 convenient to edit Setup.local and leave Setup alone. Then, when
886 installing a new Python version, you can copy your old Setup.local
890 Setting the optimization/debugging options
891 ------------------------------------------
893 If you want or need to change the optimization/debugging options for
894 the C compiler, assign to the OPT variable on the toplevel make
895 command; e.g. "make OPT=-g" will build a debugging version of Python
896 on most platforms. The default is OPT=-O; a value for OPT in the
897 environment when the configure script is run overrides this default
898 (likewise for CC; and the initial value for LIBS is used as the base
899 set of libraries to link with).
901 When compiling with GCC, the default value of OPT will also include
902 the -Wall and -Wstrict-prototypes options.
904 Additional debugging code to help debug memory management problems can
905 be enabled by using the --with-pydebug option to the configure script.
907 For flags that change binary compatibility, use the EXTRA_CFLAGS
914 If you want C profiling turned on, the easiest way is to run configure
915 with the CC environment variable to the necessary compiler
916 invocation. For example, on Linux, this works for profiling using
919 CC="gcc -pg" ./configure
921 Note that on Linux, gprof apparently does not work for shared
922 libraries. The Makefile/Setup mechanism can be used to compile and
923 link most extension modules statically.
929 To test the interpreter, type "make test" in the top-level directory.
930 This runs the test set twice (once with no compiled files, once with
931 the compiled files left by the previous test run). The test set
932 produces some output. You can generally ignore the messages about
933 skipped tests due to optional features which can't be imported.
934 If a message is printed about a failed test or a traceback or core
935 dump is produced, something is wrong. On some Linux systems (those
936 that are not yet using glibc 6), test_strftime fails due to a
937 non-standard implementation of strftime() in the C library. Please
938 ignore this, or upgrade to glibc version 6.
940 IMPORTANT: If the tests fail and you decide to mail a bug report,
941 *don't* include the output of "make test". It is useless. Run the
942 failing test manually, as follows:
944 ./python ./Lib/test/test_whatever.py
946 (substituting the top of the source tree for '.' if you built in a
947 different directory). This runs the test in verbose mode.
953 To install the Python binary, library modules, shared library modules
954 (see below), include files, configuration files, and the manual page,
959 This will install all platform-independent files in subdirectories of
960 the directory given with the --prefix option to configure or to the
961 `prefix' Make variable (default /usr/local). All binary and other
962 platform-specific files will be installed in subdirectories if the
963 directory given by --exec-prefix or the `exec_prefix' Make variable
964 (defaults to the --prefix directory) is given.
966 If DESTDIR is set, it will be taken as the root directory of the
967 installation, and files will be installed into $(DESTDIR)$(prefix),
968 $(DESTDIR)$(exec_prefix), etc.
970 All subdirectories created will have Python's version number in their
971 name, e.g. the library modules are installed in
972 "/usr/local/lib/python<version>/" by default, where <version> is the
973 <major>.<minor> release number (e.g. "2.1"). The Python binary is
974 installed as "python<version>" and a hard link named "python" is
975 created. The only file not installed with a version number in its
976 name is the manual page, installed as "/usr/local/man/man1/python.1"
979 If you have a previous installation of Python that you don't
980 want to replace yet, use
984 This installs the same set of files as "make install" except it
985 doesn't create the hard link to "python<version>" named "python" and
986 it doesn't install the manual page at all.
988 The only thing you may have to install manually is the Python mode for
989 Emacs found in Misc/python-mode.el. (But then again, more recent
990 versions of Emacs may already have it.) Follow the instructions that
991 came with Emacs for installation of site-specific files.
993 On Mac OS X, if you have configured Python with --enable-framework, you
994 should use "make frameworkinstall" to do the installation. Note that this
995 installs the Python executable in a place that is not normally on your
996 PATH, you may want to set up a symlink in /usr/local/bin.
999 Configuration options and variables
1000 -----------------------------------
1002 Some special cases are handled by passing options to the configure
1005 WARNING: if you rerun the configure script with different options, you
1006 must run "make clean" before rebuilding. Exceptions to this rule:
1007 after changing --prefix or --exec-prefix, all you need to do is remove
1010 --with(out)-gcc: The configure script uses gcc (the GNU C compiler) if
1011 it finds it. If you don't want this, or if this compiler is
1012 installed but broken on your platform, pass the option
1013 --without-gcc. You can also pass "CC=cc" (or whatever the
1014 name of the proper C compiler is) in the environment, but the
1015 advantage of using --without-gcc is that this option is
1016 remembered by the config.status script for its --recheck
1019 --prefix, --exec-prefix: If you want to install the binaries and the
1020 Python library somewhere else than in /usr/local/{bin,lib},
1021 you can pass the option --prefix=DIRECTORY; the interpreter
1022 binary will be installed as DIRECTORY/bin/python and the
1023 library files as DIRECTORY/lib/python/*. If you pass
1024 --exec-prefix=DIRECTORY (as well) this overrides the
1025 installation prefix for architecture-dependent files (like the
1026 interpreter binary). Note that --prefix=DIRECTORY also
1027 affects the default module search path (sys.path), when
1028 Modules/config.c is compiled. Passing make the option
1029 prefix=DIRECTORY (and/or exec_prefix=DIRECTORY) overrides the
1030 prefix set at configuration time; this may be more convenient
1031 than re-running the configure script if you change your mind
1032 about the install prefix.
1034 --with-readline: This option is no longer supported. GNU
1035 readline is automatically enabled by setup.py when present.
1037 --with-threads: On most Unix systems, you can now use multiple
1038 threads, and support for this is enabled by default. To
1039 disable this, pass --with-threads=no. If the library required
1040 for threads lives in a peculiar place, you can use
1041 --with-thread=DIRECTORY. IMPORTANT: run "make clean" after
1042 changing (either enabling or disabling) this option, or you
1043 will get link errors! Note: for DEC Unix use
1044 --with-dec-threads instead.
1046 --with-sgi-dl: On SGI IRIX 4, dynamic loading of extension modules is
1047 supported by the "dl" library by Jack Jansen, which is
1048 ftp'able from ftp://ftp.cwi.nl/pub/dynload/dl-1.6.tar.Z.
1049 This is enabled (after you've ftp'ed and compiled the dl
1050 library) by passing --with-sgi-dl=DIRECTORY where DIRECTORY
1051 is the absolute pathname of the dl library. (Don't bother on
1052 IRIX 5, it already has dynamic linking using SunOS style
1053 shared libraries.) THIS OPTION IS UNSUPPORTED.
1055 --with-dl-dld: Dynamic loading of modules is rumored to be supported
1056 on some other systems: VAX (Ultrix), Sun3 (SunOS 3.4), Sequent
1057 Symmetry (Dynix), and Atari ST. This is done using a
1058 combination of the GNU dynamic loading package
1059 (ftp://ftp.cwi.nl/pub/dynload/dl-dld-1.1.tar.Z) and an
1060 emulation of the SGI dl library mentioned above (the emulation
1062 ftp://ftp.cwi.nl/pub/dynload/dld-3.2.3.tar.Z). To
1063 enable this, ftp and compile both libraries, then call
1064 configure, passing it the option
1065 --with-dl-dld=DL_DIRECTORY,DLD_DIRECTORY where DL_DIRECTORY is
1066 the absolute pathname of the dl emulation library and
1067 DLD_DIRECTORY is the absolute pathname of the GNU dld library.
1068 (Don't bother on SunOS 4 or 5, they already have dynamic
1069 linking using shared libraries.) THIS OPTION IS UNSUPPORTED.
1071 --with-libm, --with-libc: It is possible to specify alternative
1072 versions for the Math library (default -lm) and the C library
1073 (default the empty string) using the options
1074 --with-libm=STRING and --with-libc=STRING, respectively. For
1075 example, if your system requires that you pass -lc_s to the C
1076 compiler to use the shared C library, you can pass
1077 --with-libc=-lc_s. These libraries are passed after all other
1078 libraries, the C library last.
1080 --with-libs='libs': Add 'libs' to the LIBS that the python interpreter
1083 --with-cxx-main=<compiler>: If you plan to use C++ extension modules,
1084 then -- on some platforms -- you need to compile python's main()
1085 function with the C++ compiler. With this option, make will use
1086 <compiler> to compile main() *and* to link the python executable.
1087 It is likely that the resulting executable depends on the C++
1088 runtime library of <compiler>. (The default is --without-cxx-main.)
1090 There are platforms that do not require you to build Python
1091 with a C++ compiler in order to use C++ extension modules.
1092 E.g., x86 Linux with ELF shared binaries and GCC 3.x, 4.x is such
1093 a platform. We recommend that you configure Python
1094 --without-cxx-main on those platforms because a mismatch
1095 between the C++ compiler version used to build Python and to
1096 build a C++ extension module is likely to cause a crash at
1099 The Python installation also stores the variable CXX that
1100 determines, e.g., the C++ compiler distutils calls by default
1101 to build C++ extensions. If you set CXX on the configure command
1102 line to any string of non-zero length, then configure won't
1103 change CXX. If you do not preset CXX but pass
1104 --with-cxx-main=<compiler>, then configure sets CXX=<compiler>.
1105 In all other cases, configure looks for a C++ compiler by
1106 some common names (c++, g++, gcc, CC, cxx, cc++, cl) and sets
1107 CXX to the first compiler it finds. If it does not find any
1108 C++ compiler, then it sets CXX="".
1110 Similarly, if you want to change the command used to link the
1111 python executable, then set LINKCC on the configure command line.
1114 --with-pydebug: Enable additional debugging code to help track down
1115 memory management problems. This allows printing a list of all
1116 live objects when the interpreter terminates.
1118 --with(out)-universal-newlines: enable reading of text files with
1119 foreign newline convention (default: enabled). In other words,
1120 any of \r, \n or \r\n is acceptable as end-of-line character.
1121 If enabled import and execfile will automatically accept any newline
1122 in files. Python code can open a file with open(file, 'U') to
1123 read it in universal newline mode. THIS OPTION IS UNSUPPORTED.
1125 --with-tsc: Profile using the Pentium timestamping counter (TSC).
1127 --with-system-ffi: Build the _ctypes extension module using an ffi
1128 library installed on the system.
1131 Building for multiple architectures (using the VPATH feature)
1132 -------------------------------------------------------------
1134 If your file system is shared between multiple architectures, it
1135 usually is not necessary to make copies of the sources for each
1136 architecture you want to support. If the make program supports the
1137 VPATH feature, you can create an empty build directory for each
1138 architecture, and in each directory run the configure script (on the
1139 appropriate machine with the appropriate options). This creates the
1140 necessary subdirectories and the Makefiles therein. The Makefiles
1141 contain a line VPATH=... which points to a directory containing the
1142 actual sources. (On SGI systems, use "smake -J1" instead of "make" if
1143 you use VPATH -- don't try gnumake.)
1145 For example, the following is all you need to build a minimal Python
1146 in /usr/tmp/python (assuming ~guido/src/python is the toplevel
1147 directory and you want to build in /usr/tmp/python):
1149 $ mkdir /usr/tmp/python
1150 $ cd /usr/tmp/python
1151 $ ~guido/src/python/configure
1157 Note that configure copies the original Setup file to the build
1158 directory if it finds no Setup file there. This means that you can
1159 edit the Setup file for each architecture independently. For this
1160 reason, subsequent changes to the original Setup file are not tracked
1161 automatically, as they might overwrite local changes. To force a copy
1162 of a changed original Setup file, delete the target Setup file. (The
1163 makesetup script supports multiple input files, so if you want to be
1164 fancy you can change the rules to create an empty Setup.local if it
1165 doesn't exist and run it with arguments $(srcdir)/Setup Setup.local;
1166 however this assumes that you only need to add modules.)
1169 Building on non-UNIX systems
1170 ----------------------------
1172 For Windows (2000/NT/ME/98/95), assuming you have MS VC++ 7.1, the
1173 project files are in PCbuild, the workspace is pcbuild.dsw. See
1174 PCbuild\readme.txt for detailed instructions.
1176 For other non-Unix Windows compilers, in particular MS VC++ 6.0 and
1177 for OS/2, enter the directory "PC" and read the file "readme.txt".
1179 For the Mac, a separate source distribution will be made available,
1180 for use with the CodeWarrior compiler. If you are interested in Mac
1181 development, join the PythonMac Special Interest Group
1182 (http://www.python.org/sigs/pythonmac-sig/, or send email to
1183 pythonmac-sig-request@python.org).
1185 Of course, there are also binary distributions available for these
1186 platforms -- see http://www.python.org/.
1188 To port Python to a new non-UNIX system, you will have to fake the
1189 effect of running the configure script manually (for Mac and PC, this
1190 has already been done for you). A good start is to copy the file
1191 pyconfig.h.in to pyconfig.h and edit the latter to reflect the actual
1192 configuration of your system. Most symbols must simply be defined as
1193 1 only if the corresponding feature is present and can be left alone
1194 otherwise; however the *_t type symbols must be defined as some
1195 variant of int if they need to be defined at all.
1197 For all platforms, it's important that the build arrange to define the
1198 preprocessor symbol NDEBUG on the compiler command line in a release
1199 build of Python (else assert() calls remain in the code, hurting
1200 release-build performance). The Unix, Windows and Mac builds already
1204 Miscellaneous issues
1205 ====================
1210 There's an excellent Emacs editing mode for Python code; see the file
1211 Misc/python-mode.el. Originally written by the famous Tim Peters, it
1212 is now maintained by the equally famous Barry Warsaw (it's no
1213 coincidence that they now both work on the same team). The latest
1214 version, along with various other contributed Python-related Emacs
1215 goodies, is online at http://www.python.org/emacs/python-mode. And
1216 if you are planning to edit the Python C code, please pick up the
1217 latest version of CC Mode http://www.python.org/emacs/cc-mode; it
1218 contains a "python" style used throughout most of the Python C source
1219 files. (Newer versions of Emacs or XEmacs may already come with the
1220 latest version of python-mode.)
1226 The setup.py script automatically configures this when it detects a
1227 usable Tcl/Tk installation. This requires Tcl/Tk version 8.0 or
1230 For more Tkinter information, see the Tkinter Resource page:
1231 http://www.python.org/topics/tkinter/
1233 There are demos in the Demo/tkinter directory.
1235 Note that there's a Python module called "Tkinter" (capital T) which
1236 lives in Lib/lib-tk/Tkinter.py, and a C module called "_tkinter"
1237 (lower case t and leading underscore) which lives in
1238 Modules/_tkinter.c. Demos and normal Tk applications import only the
1239 Python Tkinter module -- only the latter imports the C _tkinter
1240 module. In order to find the C _tkinter module, it must be compiled
1241 and linked into the Python interpreter -- the setup.py script does
1242 this. In order to find the Python Tkinter module, sys.path must be
1243 set correctly -- normal installation takes care of this.
1246 Distribution structure
1247 ----------------------
1249 Most subdirectories have their own README files. Most files have
1252 BeOS/ Files specific to the BeOS port
1253 Demo/ Demonstration scripts, modules and programs
1254 Doc/ Documentation sources (LaTeX)
1255 Grammar/ Input for the parser generator
1256 Include/ Public header files
1257 LICENSE Licensing information
1258 Lib/ Python library modules
1259 Mac/ Macintosh specific resources
1260 Makefile.pre.in Source from which config.status creates the Makefile.pre
1261 Misc/ Miscellaneous useful files
1262 Modules/ Implementation of most built-in modules
1263 Objects/ Implementation of most built-in object types
1264 PC/ Files specific to PC ports (DOS, Windows, OS/2)
1265 PCbuild/ Build directory for Microsoft Visual C++
1266 Parser/ The parser and tokenizer and their input handling
1267 Python/ The byte-compiler and interpreter
1268 README The file you're reading now
1269 Tools/ Some useful programs written in Python
1270 pyconfig.h.in Source from which pyconfig.h is created (GNU autoheader output)
1271 configure Configuration shell script (GNU autoconf output)
1272 configure.in Configuration specification (input for GNU autoconf)
1273 install-sh Shell script used to install files
1274 setup.py Python script used to build extension modules
1276 The following files will (may) be created in the toplevel directory by
1277 the configuration and build processes:
1279 Makefile Build rules
1280 Makefile.pre Build rules before running Modules/makesetup
1281 buildno Keeps track of the build number
1282 config.cache Cache of configuration variables
1283 pyconfig.h Configuration header
1284 config.log Log from last configure run
1285 config.status Status from last run of the configure script
1286 getbuildinfo.o Object file from Modules/getbuildinfo.c
1287 libpython<version>.a The library archive
1288 python The executable interpreter
1289 tags, TAGS Tags files for vi and Emacs
1296 --Guido van Rossum (home page: http://www.python.org/~guido/)