| Authors: | Jack Jansen (2004-07)
Ronald Oussoren (2010-04) Ned Deily (2012-06) |
|---|
This document provides a quick overview of some macOS specific features in the Python distribution.
--enable-framework[=DIR]If this argument is specified the build will create a Python.framework rather than a traditional Unix install. See the section Building and using a framework-based Python on macOS for more information on frameworks.
If the optional directory argument is specified the framework is installed into that directory. This can be used to install a python framework into your home directory:
$ ./configure --enable-framework=/Users/ronald/Library/Frameworks $ make && make install
This will install the framework itself in
/Users/ronald/Library/Frameworks, the applications in a subdirectory of/Users/ronald/Applicationsand the command-line tools in/Users/ronald/bin.--with-framework-name=NAMESpecify the name for the python framework, defaults to
Python. This option is only valid when--enable-frameworkis specified.--enable-universalsdk[=PATH]Create a universal binary build of Python. This can be used with both regular and framework builds.
The optional argument specifies which macOS SDK should be used to perform the build. In most cases on current systems, you do not need to specify PATH or you can just use
/; the default MacOSX SDK for the active Xcode or Command Line Tools developer directory will be used. See the macOSxcrunman page for more information. Current versions of macOS and Xcode no longer install system header files in their traditional locations, like/usr/includeand/System/Library/Frameworks; instead they are found within a MacOSX SDK. The Apple-supplied build tools handle this transparently and current versiona of Python now handle this as well. So it is no longer necessary, and since macOS 10.14, no longer possible to force the installation of system headers withxcode-select.--with-universal-archs=VALUESpecify the kind of universal binary that should be created. This option is only valid when
--enable-universalsdkis specified. The default is32-bitif building with a SDK that supports PPC, otherwise defaults tointel. Note thatintelmeans a universal build of both 32-bit and 64-bit binaries and that may not be what you want; for example, as of macOS 10.15 Catalina, 32-bit execution is no longer supported by the operating system. Thus it is best to either explicitly specify values for--with-universal-archs:--enable-universalsdk --with-universal-archs=intel-64or avoid using either.
A universal binary build of Python contains object code for more than one
CPU architecture. A universal macOS executable file or library combines the
architecture-specific code into one file and can therefore run at native
speed on all supported architectures. Universal files were introduced in
macOS 10.4 to add support for Intel-based Macs to the existing PowerPC (PPC)
machines. In macOS 10.5 support was extended to 64-bit Intel and 64-bit PPC
architectures. It is possible to build Python with various combinations
of architectures depending on the build tools and macOS version in use.
Note that PPC support was removed in macOS 10.7 and 32-bit Intel support
was removed in macOS 10.15. So currently as of macOS 10.15, macOS only
supports one execution architecture, 64-bit Intel (x86_64).
You can enable universal binaries by specifying the "--enable-universalsdk" flag to configure:
$ ./configure --enable-universalsdk $ make $ make install
This flag can be used with a framework build of python, but also with a classic unix build. Universal builds were first supported with macOS 10.4 with Xcode 2.1 and the 10.4u SDK. Starting with Xcode 3 and macOS 10.5, more configurations are available.
In general, universal builds depend on specific features provided by the Apple-supplied compilers and other build tools included in Apple's Xcode development tools. You should install Xcode or the command line tools component appropriate for the macOS release you are running on. See the Python Developer's Guide (https://devguide.python.org/setup/) for more information.
It is possible to build a number of flavors of the universal binary build,
the default is a 32-bit only binary (i386 and ppc) in build environments that
support ppc (10.4 with Xcode 2, 10.5 and 10.6 with Xcode 3) or an
Intel-32/-64-bit binary (i386 and X86_64) in build environments that do not
support ppc (Xcode 4 on 10.6 and later systems). The flavor can be specified
using the configure option --with-universal-archs=VALUE. The following
values are available:
intel:i386,x86_64intel-32:i386intel-64:x86_6432-bit:ppc,i3863-way:i386,x86_64,ppc64-bit:ppc64,x86_64all:ppc,ppc64,i386,x86_64
To build a universal binary that includes a 64-bit architecture, you must build
on a system running macOS 10.5 or later. The all and 64-bit flavors can
only be built with a 10.5 SDK because ppc64 support was only included with
macOS 10.5. Although legacy ppc support was included with Xcode 3 on macOS
10.6, it was removed in Xcode 4, versions of which were released on macOS 10.6
and which is the standard for macOS 10.7. To summarize, the
following combinations of SDKs and universal-archs flavors are available:
- 10.4u SDK with Xcode 2 supports
32-bitonly- 10.5 SDK with Xcode 3.1.x supports all flavors
- 10.6 SDK with Xcode 3.2.x supports
intel,intel-32,intel-64,3-way, and32-bit- 10.6 SDK with Xcode 4 supports
intel,intel-32, andintel-64- 10.7 through 10.14 SDKs support
intel,intel-32, andintel-64- 10.15 and later SDKs support
intel-64only
The makefile for a framework build will also install python3.x-32
binaries when the universal architecture includes at least one 32-bit
architecture (that is, for all flavors but 64-bit and intel-64).
You can run code using a specific architecture using the arch command:
$ arch -i386 python
Or to explicitly run in 32-bit mode, regardless of the machine hardware:
$ arch -i386 -ppc python
Using arch is not a perfect solution as the selected architecture will
not automatically carry through to subprocesses launched by programs and tests
under that Python. If you want to ensure that Python interpreters launched in
subprocesses also run in 32-bit-mode if the main interpreter does, use
a python3.x-32 binary and use the value of sys.executable as the
subprocess Popen executable value.
The main reason is because you want to create GUI programs in Python. With the exception of X11/XDarwin-based GUI toolkits all GUI programs need to be run from a macOS application bundle (".app").
While it is technically possible to create a .app without using frameworks you will have to do the work yourself if you really want this.
A second reason for using frameworks is that they put Python-related items in
only two places: "/Library/Framework/Python.framework" and
"/Applications/Python <VERSION>" where <VERSION> can be e.g. "3.8",
"2.7", etc. This simplifies matters for users installing
Python from a binary distribution if they want to get rid of it again. Moreover,
due to the way frameworks work, usera without admin privileges can install a
binary distribution in their home directory without recompilation.
In everyday use there is no difference, except that things are stored in a different place. If you look in /Library/Frameworks/Python.framework you will see lots of relative symlinks, see the Apple documentation for details. If you are used to a normal unix Python file layout go down to Versions/Current and you will see the familiar bin and lib directories.
Yes, probably. If you want Tkinter support you need to get the macOS AquaTk
distribution, this is installed by default on macOS 10.4 or later. Be
aware, though, that the Cocoa-based AquaTk's supplied starting with macOS
10.6 have proven to be unstable. If possible, you should consider
installing a newer version before building on macOS 10.6 or later, such as
the ActiveTcl 8.6. See http://www.python.org/download/mac/tcltk/. If you
are building with an SDK, ensure that the newer Tcl and Tk frameworks are
seen in the SDK's Library/Frameworks directory; you may need to
manually create symlinks to their installed location, /Library/Frameworks.
If you want wxPython you need to get that.
If you want Cocoa you need to get PyObjC.
This directory contains a Makefile that will create a couple of python-related applications (full-blown macOS .app applications, that is) in "/Applications/Python <VERSION>", and a hidden helper application Python.app inside the Python.framework, and unix tools including "python" into /usr/local/bin. In addition it has a target "installmacsubtree" that installs the relevant portions of the Mac subtree into the Python.framework.
It is normally invoked indirectly through the main Makefile, as the last step in the sequence
- ./configure --enable-framework
- make
- make install
This sequence will put the framework in /Library/Framework/Python.framework,
the applications in /Applications/Python <VERSION> and the unix tools in
/usr/local/bin.
Installing in another place, for instance $HOME/Library/Frameworks if you
have no admin privileges on your machine, is possible. This can be accomplished
by configuring with --enable-framework=$HOME/Library/Frameworks.
The other two directories will then also be installed in your home directory,
at $HOME/Applications/Python-<VERSION> and $HOME/bin.
If you want to install some part, but not all, read the main Makefile. The frameworkinstall is composed of a couple of sub-targets that install the framework itself, the Mac subtree, the applications and the unix tools.
There is an extra target frameworkinstallextras that is not part of the normal frameworkinstall which installs the Tools directory into "/Applications/Python <VERSION>", this is useful for binary distributions.
"IDLE.app" is an integrated development environment for Python: editor, debugger, etc.
"Python Launcher.app" is a helper application that will handle things when you
double-click a .py, .pyc or .pyw file. For the first two it creates a Terminal
window and runs the scripts with the normal command-line Python. For the
latter it runs the script in the Python.app interpreter so the script can do
GUI-things. Keep the Option key depressed while dragging or double-clicking
a script to set runtime options. These options can be set persistently
through Python Launcher's preferences dialog.
The program pythonx.x runs python scripts from the command line.
Previously, various compatibility aliases were also installed, including
pythonwx.x which in early releases of Python on macOS was required to run
GUI programs. As of 3.4.0, the pythonwx.x aliases are no longer installed.
Download and unpack the source release from http://www.python.org/download/.
Go to the directory Mac/BuildScript. There you will find a script
build-installer.py that does all the work. This will download and build
a number of 3rd-party libaries, configures and builds a framework Python,
installs it, creates the installer package files and then packs this in a
DMG image. The script also builds an HTML copy of the current Python
documentation set for this release for inclusion in the framework. The
installer package will create links to the documentation for use by IDLE,
pydoc, shell users, and Finder user.
The script will build a universal binary so you'll therefore have to run this
script on macOS 10.4 or later and with Xcode 2.1 or later installed.
However, the Python build process itself has several build dependencies not
available out of the box with macOS 10.4 so you may have to install
additional software beyond what is provided with Xcode 2.
It should be possible to use SDKs and/or older
versions of Xcode to build installers that are compatible with older systems
on a newer system but this may not be completely foolproof so the resulting
executables, shared libraries, and .so bundles should be carefully
examined and tested on all supported systems for proper dynamic linking
dependencies. It is safest to build the distribution on a system running the
minimum macOS version supported.
All of this is normally done completely isolated in /tmp/_py, so it does not use your normal build directory nor does it install into /.
Because of the way the script locates the files it needs you have to run it from within the BuildScript directory. The script accepts a number of command-line arguments, run it with --help for more information.
The configure script sometimes emits warnings like the one below:
configure: WARNING: libintl.h: present but cannot be compiled configure: WARNING: libintl.h: check for missing prerequisite headers? configure: WARNING: libintl.h: see the Autoconf documentation configure: WARNING: libintl.h: section "Present But Cannot Be Compiled" configure: WARNING: libintl.h: proceeding with the preprocessor's result configure: WARNING: libintl.h: in the future, the compiler will take precedence configure: WARNING: ## -------------------------------------- ## configure: WARNING: ## Report this to http://bugs.python.org/ ## configure: WARNING: ## -------------------------------------- ##
This almost always means you are trying to build a universal binary for
Python and have libraries in /usr/local that don't contain the required
architectures. Temporarily move /usr/local aside to finish the build.
Uninstalling a framework can be done by manually removing all bits that got installed. That's true for both installations from source and installations using the binary installer. macOS does not provide a central uninstaller.
The main bit of a framework install is the framework itself, installed in
/Library/Frameworks/Python.framework. This can contain multiple versions
of Python, if you want to remove just one version you have to remove the
version-specific subdirectory: /Library/Frameworks/Python.framework/Versions/X.Y.
If you do that, ensure that /Library/Frameworks/Python.framework/Versions/Current
is a symlink that points to an installed version of Python.
A framework install also installs some applications in /Applications/Python X.Y,
And lastly a framework installation installs files in /usr/local/bin, all of
them symbolic links to files in /Library/Frameworks/Python.framework/Versions/X.Y/bin.