The #! marker at the beginning of scripts is called a shebang.
The #! marker at the beginning of scripts is called a shebang.
See
Questions tagged [shebang]
486 questions
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What is the preferred Bash shebang ("#!")?
Is there any Bash shebang objectively better than the others for most uses?
#!/usr/bin/env bash
#!/bin/bash
#!/bin/sh
#!/bin/sh -
etc
I vaguely recall a long time ago hearing that adding a dash to the end prevents someone passing a command to your…
bgibson
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Why do people write "#!/usr/bin/env python" on the first line of a Python script?
I see these at the top of Python files:
#!/usr/bin/env python
#!/usr/bin/env python3
It seems to me that the files run the same without that line.
john garcias
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Should I put #! (shebang) in Python scripts, and what form should it take?
Should I put the shebang in my Python scripts? In what form?
#!/usr/bin/env python
or
#!/usr/local/bin/python
Are these equally portable? Which form is used most?
Note: the tornado project uses the shebang. On the other hand the Django project…
treecoder
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Why do you need to put #!/bin/bash at the beginning of a script file?
I have made Bash scripts before and they all ran fine without #!/bin/bash at the beginning.
What's the point of putting it in? Would things be any different?
Also, how do you pronounce #? I know that ! is pronounced as "bang."
How is #! pronounced?
node ninja
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What is the difference between "#!/usr/bin/env bash" and "#!/usr/bin/bash"?
In the header of a Bash script, what's the difference between those two statements:
#!/usr/bin/env bash
#!/usr/bin/bash
When I consulted the env man page, I get this definition:
env - run a program in a modified environment
What does it mean?
Salah Eddine Taouririt
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Why is #!/usr/bin/env bash superior to #!/bin/bash?
I've seen in a number of places, including recommendations on this site (What is the preferred Bash shebang?), to use #!/usr/bin/env bash in preference to #!/bin/bash. I've even seen one enterprising individual suggest using #!/bin/bash was wrong…
spugm1r3
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What does the line "#!/bin/sh" mean in a UNIX shell script?
I was going through some shell script tutorials and found the following sample program:
#!/bin/sh
clear
echo "HELLO WORLD"
Can anyone please tell me what the significance of the comment #!/bin/sh at the start is?
Jake
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What exactly does "/usr/bin/env node" do at the beginning of node files?
I had seen this line #!/usr/bin/env node at the beginning of some examples in nodejs and I had googled without finding any topic that could answer the reason for that line.
The nature of the words makes search it not that easy.
I'd read some…
Gepser Hoil
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Appropriate hashbang for Node.js scripts
I'm trying to create a script for node.js that will work in multiple environments. Particularly for me, I'm switching back and forth between OS X and Ubuntu. In the former, Node is installed as node, but in the latter it is nodejs. At the top of…
Explosion Pills
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How to use multiple arguments for awk with a shebang (i.e. #!)?
I'd like to execute an gawk script with --re-interval using a shebang. The "naive" approach of
#!/usr/bin/gawk --re-interval -f
... awk script goes here
does not work, since gawk is called with the first argument "--re-interval -f" (not splitted…
Dr. Hans-Peter Störr
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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…
dsimcha
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Cannot pass an argument to python with "#!/usr/bin/env python"
I needed to have a directly executable python script, so i started the file with #!/usr/bin/env python. However, I also need unbuffered output, so i tried #!/usr/bin/env python -u, but that fails with python -u: no such file or directory.
I found…
Eskil
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node and shebang : help executing via command line
My node installation is at:
/usr/local/bin/node
and I've added the shebang:
#!/usr/local/bin/node
to the top of the file and given my node app file the permissions 755, but when I try to run:
> ./my-app
I get the old:
-bash: ./my-app: No such file…
asking
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How does /usr/bin/env work in a Linux shebang line?
I know shebang line like this:
#!/bin/sh
but I found out I can also use shebang line like this:
#!/usr/bin/env python3
This confuses me, can someone explain to me how Linux will process this one?
user1187968
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What's the difference between python shebangs with /usr/bin/env rather than hard-path?
I used to use the shebang
#!/usr/bin/env python
When is it better to use
#!/usr/bin/python
What is the exact difference between them?
Ken
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