# python-build python-build is a [pyenv](https://github.com/pyenv/pyenv) plugin that provides a `pyenv install` command to compile and install different versions of Python on UNIX-like systems. You can also use python-build without pyenv in environments where you need precise control over Python version installation. See the [list of releases](https://github.com/pyenv/pyenv/releases) for changes in each version. ## Installation ### Installing as a pyenv plugin (recommended) You need nothing to do since python-build is bundled with pyenv by default. ### Installing as a standalone program (advanced) Installing python-build as a standalone program will give you access to the `python-build` command for precise control over Python version installation. If you have pyenv installed, you will also be able to use the `pyenv install` command. git clone git://github.com/pyenv/pyenv.git cd pyenv/plugins/python-build ./install.sh This will install python-build into `/usr/local`. If you do not have write permission to `/usr/local`, you will need to run `sudo ./install.sh` instead. You can install to a different prefix by setting the `PREFIX` environment variable. To update python-build after it has been installed, run `git pull` in your cloned copy of the repository, then re-run the install script. ### Installing with Homebrew (for OS X users) Mac OS X users can install python-build with the [Homebrew](http://brew.sh) package manager. This will give you access to the `python-build` command. If you have pyenv installed, you will also be able to use the `pyenv install` command. *This is the recommended method of installation if you installed pyenv with Homebrew.* brew install pyenv Or, if you would like to install the latest development release: brew install --HEAD pyenv ## Usage Before you begin, you should ensure that your build environment has the proper system dependencies for compiling the wanted Python Version (see our [recommendations](https://github.com/pyenv/pyenv/wiki#suggested-build-environment)). ### Using `pyenv install` with pyenv To install a Python version for use with pyenv, run `pyenv install` with exact name of the version you want to install. For example, pyenv install 2.7.4 Python versions will be installed into a directory of the same name under `~/.pyenv/versions`. To see a list of all available Python versions, run `pyenv install --list`. You may also tab-complete available Python versions if your pyenv installation is properly configured. ### Using `python-build` standalone If you have installed python-build as a standalone program, you can use the `python-build` command to compile and install Python versions into specific locations. Run the `python-build` command with the exact name of the version you want to install and the full path where you want to install it. For example, python-build 2.7.4 ~/local/python-2.7.4 To see a list of all available Python versions, run `python-build --definitions`. Pass the `-v` or `--verbose` flag to `python-build` as the first argument to see what's happening under the hood. ### Custom definitions Both `pyenv install` and `python-build` accept a path to a custom definition file in place of a version name. Custom definitions let you develop and install versions of Python that are not yet supported by python-build. See the [python-build built-in definitions](https://github.com/pyenv/pyenv/tree/master/plugins/python-build/share/python-build) as a starting point for custom definition files. [definitions]: https://github.com/pyenv/pyenv/tree/master/plugins/python-build/share/python-build ### Special environment variables You can set certain environment variables to control the build process. * `TMPDIR` sets the location where python-build stores temporary files. * `PYTHON_BUILD_BUILD_PATH` sets the location in which sources are downloaded and built. By default, this is a subdirectory of `TMPDIR`. * `PYTHON_BUILD_CACHE_PATH`, if set, specifies a directory to use for caching downloaded package files. * `PYTHON_BUILD_MIRROR_URL` overrides the default mirror URL root to one of your choosing. * `PYTHON_BUILD_SKIP_MIRROR`, if set, forces python-build to download packages from their original source URLs instead of using a mirror. * `PYTHON_BUILD_ROOT` overrides the default location from where build definitions in `share/python-build/` are looked up. * `PYTHON_BUILD_DEFINITIONS` can be a list of colon-separated paths that get additionally searched when looking up build definitions. * `CC` sets the path to the C compiler. * `PYTHON_CFLAGS` lets you pass additional options to the default `CFLAGS`. Use this to override, for instance, the `-O3` option. * `CONFIGURE_OPTS` lets you pass additional options to `./configure`. * `MAKE` lets you override the command to use for `make`. Useful for specifying GNU make (`gmake`) on some systems. * `MAKE_OPTS` (or `MAKEOPTS`) lets you pass additional options to `make`. * `MAKE_INSTALL_OPTS` lets you pass additional options to `make install`. * `PYTHON_CONFIGURE_OPTS` and `PYTHON_MAKE_OPTS` and `PYTHON_MAKE_INSTALL_OPTS` allow you to specify configure and make options for building CPython. These variables will be passed to Python only, not any dependent packages (e.g. libyaml). ### Applying patches to Python before compiling Both `pyenv install` and `python-build` support the `--patch` (`-p`) flag that signals that a patch from stdin should be applied to Python, Jython or PyPy source code before the `./configure` and compilation steps. Example usage: ```sh # applying a single patch $ pyenv install --patch 2.7.10 < /path/to/python.patch # applying a patch from HTTP $ pyenv install --patch 2.7.10 < <(curl -sSL http://git.io/python.patch) # applying multiple patches $ cat fix1.patch fix2.patch | pyenv install --patch 2.7.10 ``` ### Building with `--enable-shared` You can build CPython with `--enable-shared` to install a version with shared object. If `--enable-shared` was found in `PYTHON_CONFIGURE_OPTS` or `CONFIGURE_OPTS`, `python-build` will automatically set `RPATH` to the pyenv's prefix directory. This means you don't have to set `LD_LIBRARY_PATH` or `DYLD_LIBRARY_PATH` for the version(s) installed with `--enable-shared`. ```sh $ env PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install 2.7.9 ``` ### Checksum verification If you have the `shasum`, `openssl`, or `sha256sum` tool installed, python-build will automatically verify the SHA2 checksum of each downloaded package before installing it. Checksums are optional and specified as anchors on the package URL in each definition. (All bundled definitions include checksums.) ### Package download mirrors python-build will first attempt to download package files from a mirror hosted on GitHub Pages. If a package is not available on the mirror, if the mirror is down, or if the download is corrupt, python-build will fall back to the official URL specified in the definition file. You can point python-build to another mirror by specifying the `PYTHON_BUILD_MIRROR_URL` environment variable--useful if you'd like to run your own local mirror, for example. Package mirror URLs are constructed by joining this variable with the SHA2 checksum of the package file. If you don't have an SHA2 program installed, python-build will skip the download mirror and use official URLs instead. You can force python-build to bypass the mirror by setting the `PYTHON_BUILD_SKIP_MIRROR` environment variable. The official python-build download mirror is provided by [GitHub Pages](http://yyuu.github.io/pythons/). ### Package download caching You can instruct python-build to keep a local cache of downloaded package files by setting the `PYTHON_BUILD_CACHE_PATH` environment variable. When set, package files will be kept in this directory after the first successful download and reused by subsequent invocations of `python-build` and `pyenv install`. The `pyenv install` command defaults this path to `~/.pyenv/cache`, so in most cases you can enable download caching simply by creating that directory. ### Keeping the build directory after installation Both `python-build` and `pyenv install` accept the `-k` or `--keep` flag, which tells python-build to keep the downloaded source after installation. This can be useful if you need to use `gdb` and `memprof` with Python. Source code will be kept in a parallel directory tree `~/.pyenv/sources` when using `--keep` with the `pyenv install` command. You should specify the location of the source code with the `PYTHON_BUILD_BUILD_PATH` environment variable when using `--keep` with `python-build`. ## Getting Help Please see the [pyenv wiki](https://github.com/pyenv/pyenv/wiki) for solutions to common problems. [wiki]: https://github.com/pyenv/pyenv/wiki If you can't find an answer on the wiki, open an issue on the [issue tracker](https://github.com/pyenv/pyenv/issues). Be sure to include the full build log for build failures.