how to make python script self-executable [duplicate]

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Closed 13 years ago.

Possible Duplicate:
Calling a python script from command line without typing “python” first

I've tried

bash$ chmod +x script.py 

doesn't work. I also remember to put

#!usr/bin/env python 

at the beginning of the script.

bash$ ./script.py 

Does nothing, it just changes my cursor to a cross lol

UPDATE: I've fixed

#!/usr/bin/python 

i've also tried

chmod a+x script.py 

still nothing. My script has import commands and uses sys.argv...I've followed the instruction on this link (look at the end of the page). Nothing works

• Paul Nathan: What does your script actually do? Have you tried this with a hello.py? I usually use #!/usr/bin/python and chmod 755 hello.py.
• Pete Wilson: bash$ chmod a+x script.py . Gotta' say who gets to execute the script.
• Laurence Gonsalves: Just FYI: the reason your cursor is turning into a cross is that your script is being interpreted as a shell script since you messed up the shebang (see @TokenMacGuy's answer). That means your "import" statement is running the command import, which takes a screenshot. You may now have a PNG file lying around named sys, os, or something similar...
• BPm: you're right. there is import command. how do i fix that? i already fixed the "shebang" and it's still the same
• Laurence Gonsalves: @Pete: no, you don't. Without a "who", the symbolic form of chmod behaves almost as though you used a, though it's filtered by your umask.

Answer 1

Here is the list of things to try, in rough order of likelihood:

• Ensure that the shebang line has correct syntax (you've done this already, #!/usr/bin/python).
• Make sure the shebang is the first line in the file (not even a blank line or a comment above it).
• Verify that /usr/bin/python actually exists and works. Your Python interpreter may be installed elsewhere. Type /usr/bin/python at a prompt and make sure Python starts. Type which python if you don't know where it is installed.
• If . is not in your PATH (it may not be), you must run your script with ./script.py because the shell does not look for commands in the current directory by default.
• Make sure the executable bit is set on your script (+x, verify with ls -l).
• Make sure that you are using LF only line endings in your editor. Shells can be picky, and your shebang line must end with LF only and not CRLF. This is only likely to be a problem if you're using a Windows text editor, but it might be worth checking.
• Make sure that your text editor does not silently insert a UTF-8 BOM at the start of the file. Again, this is only likely if you're using Notepad on Windows.

Answer 2

the "shebang" needs to contain the full path to the executable. You're calling env, which is good, but you haven't given it the full path: start your script like so:

#!/usr/bin/env python 
# ^

• krs1: Beat me to it. Curse you, TokenMacGuy... bump.