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Shebang Notation: Python Scripts on Windows and Linux?

I have some small utility scripts written in Python that I want to be usable on both Windows and Linux. I want to avoid having to explicitly invoke the Python interpreter. Is there an easy way to point shebang notation to the correct locations on both Windows and Linux? If not, is there another way to allow implicit invocation of the Python interpreter on both Windows and Linux without having to modify the script when transferring between operating systems?

Edit: The shebang support on Windows is provided Cygwin, but I want to use the native Windows Python interpreter on Windows, not the Cygwin one.

Edit # 2: It appears that shebang notation overrides file associations in Cygwin terminals. I guess I could just uninstall Cygwin Python and symlink /usr/bin/python to Windows-native Python.

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dsimcha Avatar asked Sep 27 '11 19:09

dsimcha


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Does python shebang work on Windows?

Unless you are using cygwin, windows has no shebang support. However, when you install python, it add as file association for . py files. If you put just the name of your script on the command line, or double click it in windows explorer, then it will run through python.

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The first line of all your Python programs should be a shebang line, which tells your computer that you want Python to execute this program. The shebang line begins with #! , but the rest depends on your operating system. On Windows, the shebang line is #! python3 .

Does shebang line work in Windows?

The installer associates . py (console) and . pyw (GUI) script file types with the respectively named launchers, py.exe and pyw.exe, in order to enable shebang support for scripts in Windows. For an all-users installation, the launchers are installed to the Windows folder (i.e. %SystemRoot% ).

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2 Answers

Read up on the Python Launcher for Windows in the docs, which was initially described in PEP 397. It lets you define custom shebang configurations in "py.ini" (e.g. to use pypy), and out of the box you can use virtual shebangs such as #!/usr/bin/env python3, or shebangs with real paths such as #!"C:\Python33\python.exe". (Quoting is required for paths containing spaces.) You can also add command-line options to a shebang. For example, the following shebang adds the option to enter interactive mode after the script terminates: #!/usr/bin/python3 -i.

The installer associates .py (console) and .pyw (GUI) script file types with the respectively named launchers, py.exe and pyw.exe, in order to enable shebang support for scripts in Windows. For an all-users installation, the launchers are installed to the Windows folder (i.e. %SystemRoot%). For a per-user installation, you may need to manually add the installation directory to PATH in order to use py.exe in the shell (*). Then from the command line you can run Python via py -2, py -3, py -2.6, py -3.3-32 (32-bit), and so on. The launcher is handy when combined with -m to run a module as a script using a particular version of the interpreter, e.g. py -3 -m pip install.


(*) The new installer in 3.5+ defaults to "%LocalAppData%\Programs\Python\Launcher" for a per-user installation of the launcher, instead of installing it beside "python.exe", and it automatically adds this directory to PATH.

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Eryk Sun Avatar answered Sep 18 '22 14:09

Eryk Sun


Unless you are using cygwin, windows has no shebang support. However, when you install python, it add as file association for .py files. If you put just the name of your script on the command line, or double click it in windows explorer, then it will run through python.

What I do is include a #!/usr/bin/env python shebang in my scripts. This allows for shebang support on linux. If you run it on a windows machine with python installed, then the file association should be there, and it will run as well.

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Spencer Rathbun Avatar answered Sep 21 '22 14:09

Spencer Rathbun