What's the Correct Shebang Line for My Python Script?

Shebang Line in Python Scripts: Usage and Compatibility

Introduction

The shebang line in a programming script specifies the interpreter to be used for executing the script. It is especially useful for allowing a script to be executed as a standalone executable. In this discussion, we will explore the appropriate usage of the shebang line in Python scripts.

Correct Usage for Python 3 and Python 2

For Python 3 scripts, it is recommended to use the following shebang line:

#!/usr/bin/env python3

For Python 2 scripts, the following shebang line is preferred:

#!/usr/bin/env python2

These shebang lines ensure that the specified version of Python is used, regardless of system configurations or installed Python versions.

Why not #!/usr/bin/env python?

The shebang line #!/usr/bin/env python is not recommended. While it may work on some systems, it can lead to unpredictable behavior. PEP 394 suggests avoiding this format as python may refer to either Python 2 or Python 3 in different installations.

Avoid #!/usr/local/bin/python

Similarly, the shebang line #!/usr/local/bin/python should not be used. Python may not be installed at that specific location, resulting in execution failures.

Conclusion

Using the appropriate shebang line is crucial for ensuring the portability and correct execution of Python scripts. The recommended shebang lines for Python 3 and Python 2, as stated above, provide the most reliable results across different systems.

The above is the detailed content of What's the Correct Shebang Line for My Python Script?. For more information, please follow other related articles on the PHP Chinese website!